320863-1 -F INVESTIGATION OF TRI-BAND ENTERTAINMENT ANTENNA SYSTEMS ON FORD VEHICLES by Dipak L. Sengupta and Joseph E. Ferris The Radiation Laboratory Department of Electrical and Computer Engineering University of Michigan Ann Arbor, Michigan 48109 Final Report 17 April 1978 - 31 October 1978 November 1978 Purchase Order No. 47-J-597210 Prepared For Ford Motor Comoany Electrical and Electronics Division Radio and Speed Control Encineering Dept. EEE Building, Room A170 Dearborn, Michiaan 48121

EXECUTIVE SUMMARY The impedance and radiation characteristics of various tri-band antennas mounted on a number of Ford-built vehicles have been studied experimentally. The vehicles chosen were 1978 models: Light Truck, Van, Mark V, Lincoln, Cougar, LTD II, Granada, Monarch, Bronco, Fiesta, and a 1979 Model LTD. Loaded (base, sub-base and center loaded) an unloaded antennas, manual and power operated types, were used as test antennas. The program involved the measurement of the horizontal plane radiation patterns of test antennas, the received signal strenths, and the impedances at the desired terminals with the test antennas mounted at appropriate locations on the selected vehicle. The relative sensitivities of the test antennas were obtained by comparing the patterns of the test antennas with those of reference antennas. The CB reference antenna was a standard quarter wavelength monopole mounted on the roof of the vehicle and the AM/FM reference antenna was the standard AM/FM entertainment antenna mounted at its appropriate location. The VSWR results were derived from the measured impedances. In addition to the above, the CB isolation characteristics at the FM port of the splitter box and the antenna system C and Q at the AM band frequencies were measured. The impedance characteristics of some typical splitter boxes were also measured at CB and FM frequencies. Four distinct studies were carried out during the program. These were: (i) determination of the performance characteristics of various sub-base loaded tri-band antenna systems (Chapter IV), (ii) determination of the performance differences between power tri-band antennas with in-line capacitors at the radio connector and in the splitter box (Chaper V), (iii) determination of performance differences between three 1979 Ford/Mercury antenna systems: (a) 123 pf (production) system, (b) 95 pF (series capacitance) system and (c) 202 pf (RG59U Cable) system (Chaper VI), (iv) investigation of the impedance characteristics of selected splitter boxes (Chapter VII). For each test antenna mounted on a selected vehicle, some or all of the following results are presented: (i) horizontal plane radiation patterns at three selected CB (channels 1, 19 and 40) and FM band (88, 98 and 108 MHz) frequencies, (ii) CB and FM band impedances at the appropriate ports, i

(iii) the field strengths received at three selected frequencies in the AM band, (iv) relative sensitivity at CB, FM and AM bands, (v) VSWR vs frequency at CB and FM bands, and (vi) antenna system C and Q in the AM band. On the basis of these results tables have been prepared to show the relative performance of the test antennas mounted on a test vehicle, as well as the vehicle effects on the performance of a test antenna. Detailed impedance characteristics at CB and FM frequencies for four commercial splitter boxes using typical tri-band antennas mounted on a ground plane are also presented. The results are then used to evaluate the performance of existing splitter boxes. Significant findings of the study are: (i) The production series antennas have the best, and the MS-series antennas the worst, overall performance with all vehicles. All tri-band antennas when properly tuned maintain acceptable VSWR at CB frequencies on all test vehicles. Usually, the FM band VSWR is fairly large (typically larger than 5) and as a result the FM band sensitivity is degraded. (ii) The use of a padder capacitor at the radio input generally increases the AM sensitivity of the SLC antennas and appears to improve their overall performance. (iii) The Panther Program indicates that 123pF input capacitance of the antenna system provides optimum performance. (iv) The splitter box provides poor performance at the FM band frequencies. On the basis of the results obtained, it appears that the FM band performance of existing splitter boxes can be improved by introducing some variable reactance in series with the FM branch circuit of the splitter box. It is recommended that further study be initiated along this line. ii

320863-1 -F TABLE OF CONTENTS Page No. EXECUTIVE SUMMARY......................... i I. INTRODUCTION..................... 1 II. OUTLINE OF THE MEASUREMENT PROCEDURES............ 2 2.1. Radiation Pattern Measurement............. 2 2.2. Impedance Measurement.................. 4 2.3. Signal Isolation Measurement............... 7 2.4. Measurement of Effective C and Q............. 7 2.5. Measurement of Splitter Box Impedance........... 7 2.6. Test Frequencies................... 8 2.7. Comments....................... 8 III. TEST ANTENNAS AND VEHICLES.................. 9 IV. BASE AND SUB-BASE LOADED ANTENNAS............... 15 4.1. Light Truck........................ 15 Performance Comparison Chart................ 26 4.2. Van...................... 19 Performance Comparison Chart.............. 36 4.3. LTD II, Cougar/T-Bird................... 37 Performance Comparison Chart.......... 46 4.4. Bronco........................... 37 Performance Comparison Chart................ 56 4.5. Fiesta........................... 37 Performance Comparison Chart................ 66 4.6. Granada/Monarch/Versailles................. 37 Performance Comparison Chart.......... 75 4.7. Discussion......................... 37 V. REAR POWER TRI-BAND ANTENNAS WITH IN-LINE CAPACITORS......78 5.1. Mark V.......................... 78 iii

320863-1-F Page No. 5.2. Lincoln.......................... 86 5.3. Cougar........................... 86 5.4. Versailles........................ 86 5.5. Performance Comparison.................. 112 VI. PANTHER PROGRAM.......................114 6.1. Manual Entertainment (ME) Antennas on LTD.......... 114 6.2. Power Entertainment (PE) Antennas on LTD......... 114 6.3. Manual Tri-band (MT) Antennas on LTD............ 124 6.4. Power Tri-band (PT) Antennas on LTD.......... 124 6.5. Performance Comparison for Antennas on LTD....... 124 6.6. Results for Antennas on 1978 Lincoln Mark V.....1. 142 6.7. Discussion......................... 144 VII. STUDY OF SPLITTER BOX....................... 162 7.1. Results.......................... 162 7.2. Discussion.......................165 7.3. Recommendation....................... 174 VIII. ACKNOWLEDGEMENT......................... 175 IX. REFERENCES............................. 176 X. APPENDIX A.......................177 Motorola Antenna Performance............... 177 Performance Comparison Chart..............187 iv

I. INTRODUCTION This report presents the results of an experimental study of the performance of various antennas mounted on Ford vehicles and operating in the commercial AM (0.55 to 1.5 MHz), FM (88 to 108 MHz) and CB (26.965 to 27.406 MHz) bands of frequency. The vehicles chosen were light trucks, vans and passenger automobiles, all manufactured and supplied by the Ford Motor Company. The program mainly consisted of the measurement of the radiation patterns and impedances (VSWR's) of the test antennas, and of the splitter boxes associated with the test antennas. In addition, however, data were obtained for the impedance characteristics at the appropriate ports of the splitter boxes at the FM and CB frequencies, and the effective capacitance C and Q at the receiver end of the cable connecting the test antenna measured at the AM frequencies. The overall goal of the investigation was to obtain sufficient experimental data to evaluate the relative performance of the test antennas under various conditions, and to compare their performance with that of the standard AM-FM and CB antennas used with Ford vehicles. 1

II. OUTLINE OF THE MEASUREMENT PROCEDURES Standard measurement techniques were employed and it is sufficient to describe only the procedures used to obtain specific results. The radiation pattern and impedance measurements were similar to those in a previous study [1], but a description of the procedures is included here for completeness. 2.1. Radiation Pattern measurement For the radiation pattern measurements the antenna under test was installed at the desired location on a given vehicle located on a rotating platform. The test antenna radiates signals at the desired CB or FM band frequency supplied by a suitable transmitter located inside the vehicle. The CB signals were obtained from the CB transceiver installed in the vehicle; signals in the FM band were obtained from a General Radio Unit oscillator (CW) which has a nominal output power rating of 325 mw. The signals radiated by the rotating test antenna were received by a monopole antenna located at a distance of approximately 150 feet from the test vehicle. In each band, the receiving monopole consisted of a metal tubing a quarter wavelength long at the center of the band and mounted vertically at the center of a 4' x 4' ground plane placed horizontally on the surface of the earth. The CB and FM receiving monopoles were 108" and 30" long respectively, and were made of 3/8" outer diameter aluminum tubing. In general, the output of the receiving antenna was coupled to a spectrum analyzer and to a receiver and polar recorder. The spectrum analyzer was used to monitor the frequency and amplitude of the desired signal, and the nature of the ambient signals. As the vehicle was rotated, the polar recorder displayed the horizontal plane transmitting pattern of the test antenna. By the reciprocity theorem, the measured pattern is also the receiving pattern of the test antenna. Figure 1 shows the block diagram of the measurement set-up for obtaining radiation patterns at the CB and FM band frequencies. Due to the long wavelength of the AM band broadcast frequencies, the 150 feet distance between the test and receiving antennas was too small 2

RECEIVING ANTENNA ANTENNA X/4 MONOPOLE UNDER TEST 1 T —* C] 0CONDUCTI N G:~.. _ ~~^^ GROUND PLANE'/ I GROUND SURFACE ROTAT IN G PLAT FORM I 3 2 SERVO SIGNAL S —-----. -— I-N-A 4 i CITIZEN'S BAND TRANSMlITTER OR FM BAND GR UNIT OSCILLATOR W2 SPECTRUM ANALYZER HP 8558B W~ MICROWAVE RECEIVER: SCI. ATLANTA 1600 E PATTERN RECORDER:ANT. LAB POLAR RECORDER Fi ure 1: Block diagranm of the experinmental arrangenent for antenna pattern measurements at CB and FPI frequencies. 3

to provide meaningful patterns in this band. The block diagram in Figure 2 shows the experimental set-up for pattern measurements of the test antennas at these frequencies, and as indicated in Figure 2, the test antenna is used as a receiving antenna, receiving signals from a distant AM broadcast transmitting station. The horizontal plane pattern of a typical antenna obtained in this manner was found to be omnidirectional throughout the entire AM band [1]. For this reason, all the AM band field strengths were measured with a stationary vehicle at 3 selected frequencies in the AM broadcast band. The desired field strength was obtained from the resoonse of the spectrum analyzer which was used as a receiver along with the test antenna. Prior to measuring the radiation pattern of each test antenna, three calibration patterns were recorded with a standard Ford 30 inch whip antenna for the AM and FM bands, mounted in accordance with Ford Motor Company instructions, and a 108 inch monopole for the CB frequencies, mounted in the center of the roof of each test car. The calibration patterns were recorded at the desired frequencies within each frequency band. Care was exercised to ensure that the transmitter power level and the receiver sensitivity were the same for both the calibration and test antennas. 2.2. Impedance Measurement Figure 3 shows the block diagram of the experimental set-up used to measure the input impedance at the desired terminals of the test antenna. The vector voltmeter gives the input reflection coefficient from which the desired impedance and VSWR data were obtained. For each test antenna the impedance or VSWR measurements were carried out prior to the pattern measurements. Initially, the VSWR of each test antenna was measured and recorded at 27.185 MHz (Channel 19 of the CB band) with the antenna installed at the appropriate location on the test vehicle. In the event the VSWR was greater than 1.5:1, the antenna was appropriately tuned to obtain a VSWR less than 1.5:1. The VSWR's at the CB band edges 26.96 MHz (Channel 1) and 27.405 (Channel 40) were required to be less than 2.5:1. 4

INCIDENT SIGNAL FROM A LOCAL AM RADIO STATION ABOUT 10 MILES ANTENNA AWAY UNDER TEST __-^-=^ ~GROUND i/ SURFACE ROTATING PLATFORM l SPECTRUM ANALYZER: HP 8558B Figure 2: Block diagram of the experimental arrangement for antenna patterns or field strength measurement at AM frequencies. 5

4 2 -- 3 i -> ANTENNA UNDER TEST ON AN AUTOMOBILE UNIT CB FM NO W CITIZEN'S BAND FM BAND GR TRANSMITTER UNIT OSCILLATOR ( 2 18 dB ATTE-'-NU'ATlI 6 dB ATTENUT.tON E DUAL DIRECTIONAL DUAL DIRECTION'AL COUPLER COUPLER ANZAC CH 134 ANZAC CH 134 i~ VECTOR VOLTMETER VECTOR VOLTMETER HP 8405 A HP 8405 Figure 3: Block diagram showing the experimental arrangement for VSWR measurements. 6

2.3. Signal Isolation Measurement To measure the signal isolation between the CB and AM/FM oort of the splitter box of each test antenna, the output of the vehicle-installed CB transceiver was appropriately cabled to the CB port of the test antenna splitter box. A 100 ohm (5 Watt) load with a high impedance RF voltmeter (HP3406-A or equivalent) was attached in parallel with the AM/FM port of the splitter box. With the CB transceiver keyed to transmit 4 Watts of RF signal power, the RF voltmeter level wa<s observed and recorded. Typically the voltmeter reading was less than or equal to 200 millivolts and gave an indication of the degree of isolation between the two ports of the splitter box. 2.4. Measurement of Effective C and 0 With the test antenna installed on the vehicle the effective capacitance'C' and quality factor'Q' at the receiver end of the cable connecting the test antenna were measured with a standard Q-meter. These measurements were carried out at the AM band frequencies only. 2.5. Measurement of Splitter Box Impedance Figure 4 shows a schematic diagram of a splitter box with the test antenna connected at port 3. The impedance characteristics at the AM/FM Test antenna mounted on a 4' square qround olane AM/FM._.- Ground Plane 1 2 3 CB Fiqure 4. Schematic diagram of the splitter box connected to the test antenna. 7

and CB ports of the splitter box were measured according to the following scheme: (i) a. Measure impedance at the Dort 1 with port 2 terminated in 50 Q with the test antenna connected to port 3. b. Measure impedance at oort 1 with ports 2 and 3 terminated in 50. (ii) a. Measure impedance at port 2 with port 1 terminated in 100 Q with the test antenna connected to port 3. b. Measure impedance at port 2 with ports 1 and 3 terminated in 100 Q and 50 2, respectively. Note that during these measurements the test antenna was mounted on a 4' square ground plane. 2.6. Test Frequencies As mentioned earlier measurements were carried out in the AM, FM and CB bands of frequencies. The specific frequencies used for the measurements of the patterns and impedances of the test antennas were as follows: AM Band 0.8 MHz 1.2 MHz 1.6 MHz CB Band 26.965 MHz 27.185 MHz 27.405 MHz (Channel 1) (Channel 19) (Channel 40) FM Band 88 MHz 98 MHz 108 MHz 2.7. Comments The AC power supply for the test instruments inside the vehicle was obtained from the vehicle battery with the help of an inverter. This was done to avoid undesirable effects on the measured, AM band, patterns and impedances (VSWR's) produced by the long extension cord that would have been required if an external power source had been employed. The standard AM/FM antenna used had a nominal length of 31" and a cable whose length varied depending on the test car model. The antenna cable length was adjusted so that the antenna cable system provided 95 pF and 202 pF capacitance in the AM band for front and rear mounting respectively. The standard antenna used for CB frequencies was 104" long (- x/4 long at Channel 19) and was mounted vertically on the roof of the test car. 8

III. TEST ANTENNAS AND VEHICLES All the test antennas were commercially made tri-band antennas suitable for use in the FM, CB and AM bands of frequency, and were supplied by the Ford Motor Company. Basically they are monopole antennas mounted vertically at suitable locations on the given test vehicles. Each tri-band test antenna uses a loading coil whose main purpose is to increase the base current of the antenna at the CB frequencies. The loading coil itself consists of a variable inductance shunted by a capacitor, and is connected in series with the antenna. The tuning of the antenna to obtain the desired VSWR at CB frequencies is accomplished by adjusting the inductance of the loading coil. Figure 5 shows a schematic diagram of a test antenna connected to the AM/FM radio and the CB transceiver of a test vehicle. The loading coil (of variable length l1, Z2) is located at any one of the three dotted positions (A, B, C) in Figure 5. According to the locations of the loading coil the test antennas are classified as follows: Center Loaded (CL) Antennas: These are power tri-band antennas having a loading coil located in the central region (A) of the antenna. Base Loaded Antennas: These use loading coils of length z2 located at the base (B) of the antenna and above the fender of the vehicle, i.e. the ground plane of the antenna. They are manual antennas. Sub-Base Loaded Antennas: These use loading coils of length ~2 located at the base (C) of the antenna but below the ground so that the loading coils cannot be seen from outside. They are also manual antennas. Tables l(a) - (c) list the vehicles and associated test antennas evaluated. The antennas are referred to by abbreviations or by their production codes, whose meaning is an follows: CL: Power tri-band antennas with in-line capacitors in the radio connector. Antennas with code numbers starting with D: These are production triband antennas, some of which are power operated (with loading coil at the center) and some base loaded manual antennas. All are denoted 9

s.LL a) 4C) U Q1 W~~~~~~~~~ J <J ~< C) 00 I a I'~ r -,< = -~3~ ~ ~ ~~~~~4 1 LI C*. U 10 Li.. — rD LA- - l C -C= <C. 0( 4) I 0 * * U Ir T 0 t, | N | C I rr M. { 1 I (^I | C / I_ _ C I / \ a ^ II _ CL ^ Ci' 10

0 VCa -0 ~ 3: C C a<) )I. -o 0 0C) D a) a i 4.V).'-. <U i "JC 4-) 4-) CI C: 4-) (C < I r-CO- C -C -- a- a - (- 0 = a_- 4-) C S9 a- (0((%cJ0 4-0 0O ~vUco C. - = - 0 0 $.. n =( -CO S-. 4-0 C 3 CE — S I 0 CO - C L o SE- CO oU a - 4 o -- C c) -J a) a- E -C.. E4. 4 u E 4-' M EC aa a)-C', o - C C C L- 4. o C~-O(0 La.. 0.6 0 0..L' C' i. ---- c --------- s — LO) - S. - 0,a -- co 00 4- 4- | 4 - oCca: <u-o CM CO C CM0 4-: = = c_| C~4 | T ~3 C T ^S r- S- = 4-0 a-3E~j 3E (CQ ~ I = a) a) 00 a) _3 "' ri: S: 00 a b. 0lJ (3J 4CO C ("- C - SQ- 4-4o I- a- N oa - 0 U- a - S 0 - SE - SE - S-E a), —J J $..~ C CO CL; 04 - 4- c0 4- <: 4- Cc 4- S.. 4-a iz S..l ___ - -1 —----- 4-) 0 Lu 4-) 0 o - a0 ) 0.3 Cc C a CO aI - 1- a- (0 S..C a S.5 0 )- C 0.r- S- C LCL)ra- (0 4- V 3L0u O U( SOE CO -*- a- 0 I.- S-. I- Ct)?-'0. a- 0.S-..^ a..i S- S- cc 4- -0 0 S.- a) S. I eUS- l (~S. C 4- 4- 0 ~= C..) >. *r- a) "T SI..I LI) CI(- 0 00 ( 0UC1 a- a) I ) a- 0" Q, Iq — (1 —--— Lu —— 4J C O C a- C Lu < 4r C" " - =d CD CO RD u _-.J S- | r-~ (NJ'- 0 cca- c3 - Uc 4-( (0 (NJ CO E CO (0. - 0O3 4.) Lu.g 0 - E SE CO S. C....1 U~-' tj U- (04.) Lu (,4.) C4I (4UJ ~ ~ $ 0 I0 l - FE a I lml I O n I Ill j..' C0)oE co o V a)~~~Z ~ ~ ~ a C - c S0.,. L) V 3 a~=OL- (0 0- < Lu< CO C9r S 34 d Oa C- cO S. 0 S I * SJ. 0 <U 0) LU C V- VU VS 4-SQ fO 1-Cc 0J C. 0.______- *- 10 4 0 4-' a- a- S a- 3.0 a a -C 13 | 33a-CC 0E CO -^huS a- (05 a (05. E cOr 3 S -' CO' I. I III I (1 L ( L I E L 4 ~r 2 ^ -^J= C aS='O S 4 ~+J S... E. EL U. 0d a)a S-.0.00.0 OC C4C 0 Sr. T' cuvc ajc-ss~c CpU a.l->~)Ot+c b4 4-C 4 a 4)0 a- (3 S. 0 C S O U E cc E5J \\ C S.. *.,..~~ C 0.j LL 0.0k a I3 00 C.. 4 -) )... ao / \ /\( cc C o a) C-.,(0 SPUU~4U'aJ a a) S

LL C C\JL.- J. I ^ (0 o l C C - 4 CM _L. -C. > S (3 t Q-) ) c\j 1 Z:~~~~~~ CC LLI LL( LL LC. CJ 4-O C Q 4C Z 1: ~-< ~ ~ I- ). o Z -, *r.Li.. = - 0v ^ C _Q_.... - <: D f 7 S( U - ( S. o. 0. S. I — S I C(0 Z Cr:0_ C G,- m 3 I,- ~0 ( LL...: LU _C 0. SJL. --- r,,.. - t. Q,, UJ Q L I- 3 C) <J Ln cn ULL S. <:i C-%J CLLU C OJL F-.- (0 00. CO. CW *- (Q _l S- <U Q0 QCL <U S 3 CO CL OI C 0 *( o- CF ~ ~~~~~~O ~.O LO LL.. 0LL I- u CO 07LU CC C\J L 2 LU (0 00. s- -C *r C o C 0 CL LU < S.. (0 12

by the production part numbers for the splitter box assembly. RP-111-60, 20 EPL-60, 20: sub-base loaded manual tri-band antennas; the numbers 60, 20 signify the cable lengths (in inches) between the antenna and the splitter box. MS-60-, 20: sub-base loaded manual tri-band antennas, with numbers 60 and 20 having the same meaning as above. Motorola: based-loaded tri-band antenna The capacitances of the test antennas given in Table 1 (c) represent the antenna system capacitance measured at the input side of the cable looking towards the antenna; the antenna system may or may not have a padder capacitance. Some physical and other characteristics of the test antennas are given in Table 2. 13

TABLE 2. CHARACTERISTICS OF TEST ANTENNAS ANTENNA LOADING COIL Type Manual/ Lenqth Length Sub-base (S.B.) Power (Q) 1 or z2 Base (B) or Middle (M) SLC P 40 1/2" 1 1/4" M RP-111-60,20 M 40 1/2" 1 3/4" S.B. EPL-60, 20 M 41" 2" S.B.?1S-60, 20 M 41" 1 3/4" No Coil D8DF-18B812-AC M 40" 3" B D80F-18B812-CE P 40" 2 1/2" M D84F-18B812-AC P 40 1/2" 2 1/2" M D8LF-18B812-AC P 42 1/4" 2 1/2" M D8VF-18B812-AC P 39" 2 1/2" M D8UF-18B812-AC M 40" 3" B D8TF-18B812-AD M 40" 3" B D8SF-18B812-AA P 34" 2 1/2" M ME M 32 1/4" N/A N/A PE P 32" N/A N/A MT M 40" 3" B PT P 40" 2 1/2" M Motorola M 40" 2 1/2" B Std AM/FM fixed length 32" N/A N/A x/4 CB fixed length 108" --- 14

IV. BASE AND SUB-BASE LOADED ANTENNAS The results obtained with different base and sub-base loaded test antennas mounted on a variety of test vehicles are now presented and discussed. The main purpose of this set of measurements was to evaluate the performance of sub-base loaded antennas vis-a-vis the base-loaded antennas. Manual tri-band antennas were appropriately tested on 1978 models of a Light Truck, Van, Bronco, Thunderbird (T-Bird), LTD II, Cougar, Fiesta, and Granada/Monarch. 4.1. Light Truck Figures 6(a)-(c) show the horizontal plane radiation patterns at selected CB frequencies obtained with the four test antennas listed in Table l(b), of which the RP-111-20 and EPL-20 are sub-base loaded, the D8TF-18B812AD is base loaded and the MS-20 is unloaded. The corresponding patterns obtained with a standard x/4-lonq CB antenna mounted on the roof top of the test vehicle are also shown. The test antennas were mounted on the right hand side of the front fender of the test car, as shown by the inset in each of Figures 6(a)-(c). The convention in Figures 6(a)-(c) and all subsequent patterns is that the 0~ - reference angle is in the forward direction for the test car. Observe that at all the CB frequencies, the x/4-long antenna patterns are almost omnidirectional, as they should be. Since the power output from the CB transmitter was kept constant during the measurements, the results shown in Figure 6 can be used directly to estimate the CB sensitivity of a test antenna relative to that of the standard x/4-antenna. The relative sensitivity of a test antenna in a given direction may be defined as the difference (in dB) between the field strengths obtained with the test and standard A/4 antennas in that direction. The results shown in Figure 6 indicate that each of the four test antennas has less sensitivity than the standard antenna in all directions. The asymmetry in the test antenna patterns are attributed to their asymmetric location. Each of the test antenna patterns has minimum sensitivity at right angles to the forward 15

I, 2 / \ r ~~~~~~~~~~~~I /''30~~~~~~~~~~~~~~~~~~1 "' — /~~~~~~~~~~~~~~~ ~ -T-! —-' I — i /,-:~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~%\ ~ ~ ~ ~ ~ ~ 3 7- p` i... -, C S I: -\ y// e~~~~~ 16 ~~(~ i~~~ ~~~~~~~~1fr tetadrf j~aaa MS-20.:<~ ~ ~ 1

= 00 / -,, / 30i~~~~~~~.I:~~~~~~~~~~~~~~~~~~~: \Y \ A ~ ~ ~ ~ ~ r.. T~~~ I /~~~~..-<~..,< -<. CB,.eeene E.L-0 RP1'-0 0000 8T1882A, i~~~~~~~ aaa MS-20. 17

= 00; L~~~r~7 I. —7 - I iO —-— ~~~~~~ —-i~~ — 20L_ 25..Q —— 5 ~ 5-.-. — 0I --—!.5 2 i5~i,~~~~3 \,, ~, / 1~~~~~~~~~~~~~~~~~~~~~~~~>< — 5 20,, 2 ---— 25-~3 130,5:_,iv, ~i,',~ w, 7~~~~~.4 i~r:1 3 0 Figure 6(c). Radiation patterns at CB Channel 40 for test and reference antennas on 1978 Licht Truck. jY\/ EPL 20 R lll' 20, - 180 Figure~~~~~. 6(c Raito atrsa BCane 0frts neeec antnna o 1978 igh Truck. ~, i" 1(~~1

direction and on the side where the antenna is located. This is a general trend observed with all CB patterns. From Figure 6 it can be seen that the unloaded antenna (MS-20) has the least CB sensitivity in all directions. Figures 7(a)-(c) show the corresponding patterns at selected FM band frequencies obtained with the same four test antennas; the standard antenna used was the FM Entertainment antenna. Compared with the CB pattern in Figure 6, the FM-band patterns show more variations, a behavior which can be attributed to the fact that the operating wavelength is now comparable to the dimensions of the test vehicle. Here again, the test antennas are found to be less sensitive than the standard antenna, with the MS-20 antenna having the least sensitivity at 98 and 108 MHz. Figures 8 and 9 show the impedance of the test antennas at the selected CB and FM band frequencies. The corresponding VSWRs can be obtained from these results, and will be discussed later. In addition to the above, the AM band field strengths (i.e. AM-band patterns), the isolation characteristics at CB frequencies, and the system C and Q were measured for each test antenna. The results of these measurements and also the average sensitivity and VSWRs derived from Figures 6-9 are shown in Table 3, and can be used to judge the comparative performance of the four antennas tested. As regards the sensitivity and VSWR properties at the CB and FM band frequencies, the unloaded antenna (MS-20) appears to be the poorest. 4.2. Van The horizontal plane radiation patterns at CB and FM band frequencies obtained with the test antennas mounted on a van are shown in Figures 10 and 11, respectively. The patterns at the CB frequencies show variations similar to those in Figure 6 except for the considerable decrease in sensitivity in the direction near 90~. The corresponding impedances are shown in Figures 12 and 13. Table 4 summarizes the results necessary for a performance comparison. As concluded in Section 4.1, the unloaded 19

00 --- ~ ~ ~ ~ ~ (i i -1 / 35 l/ A I;' ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~~~IT 25 - \ -10~~~~~~~~~~~7 <4<~ ~~~~~~ / S ~ antennas on 1978 iIht Truck. FMReernc, PL20 RP-112,0008T1882AD AAAA MS-20.~~ 20I

00, A \ \ i~~ ~~X ~I I \\,~' —~~~~~~~~~~~~~~~-~~~~~US~ -i o.. A / A> I A- ii' ii~ ~ ~~~~~~~53 Figure 7(b). Radiation patterns at 98 MHz for test and FM reference antennas on 1978 Light Truck. FM Reference,.... EPL-20,...RP-111-20, 0000 D8TF-18B81 2-AD, AAAA MS-20. 21

- - /.-,,15,2. 2..-..-.5 --- ~. —-.-30': 3.-2 5' — 2 —— ~-04; i *1, I I / >-. ~i" ~;t: { -- I d Fiaure 7(c). Radiation patterns at 108 MHz for test and FM reference antennas on 1978 Lioht Truck. FM Refrence, EPL-2, RP-11-20,oooo D8TF-18B812-AD, 1(~F R e eene....2,....' A~AA MS-20. 22

~-~~m~t~$wi~m' ""'''"t' —u-' - |-;-. —-( —-l. -', ~ ~,,. -- i-. *-.;~~ +^^s^^-^~ — *Y;^-~" i....................'.slur-If......:,-:.........*: 3:u - l,A\IW,~~~~~~~~~~~~~~,, Sc', -,-,7' *:'"'".... - Fiqr 8...-',....., a (a) EPL-20, (b) RP-l11-20, (c) D8TF-18B812-AD, (d) MS-20.,-1~- — i~~~~~~~~~~~~d for~ test a ne n a o, 1978Lghruc (a EP-0 (bR-11-20 cDT-881-DdM-0 ~ -~-IE="i`-. ~c.~23t

S- m"-F il NM AM "N- -..... -,,,. ^ -..',-]..-.,- - * -T:-..,... ~-......;... -.. ~m.+ / (a) (b) _________"__'__-___ M to" Pow * ~.,.'.'.. -.'..' —.~.. -,.... W. _J -'', r.e.'. 9a-(.):.me-.ance c rt a 8,' 9 a 0 M' for test antennas on 1978 Li'ht Truck. (Continued on nex t page) (a)EP-0,b)RP-11-0,()DT-1882A,()MRfrn Cotinued on~ nex-t —-- page) r-1.- ------ --— f ~\_ 7-i- ~- t-2. -

14~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -'Z' -4~-p " rr~ ~ 3 "pilotMMMauILi.'.'.' -en —----—. ~ I'. /1p / -.'K- ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~, -. ~. r i d "~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~,3~~~~~~~~~a m A7 7> /~~~~~~~~...,..' xI, - i,~~~~~~~~~~~~~ 4c-1~~~~~~~~~~~~~~~~~.,,-L-50:~''.-:f.... "`-.,'~.'.'~.'... ~ —-— i~~~~~~~~~~~~~~~~~ --.. ~~~~~ - J - - - - -- - = 9.,, ~ *- 4 = -, ~~~~~,, i -- ~I ik, ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~.' n —-~~~~~~~~~~~~~~~~~~~~~~~~~~,, -I.'. "'.-., —-—.-,..'.. --- -,.. ".',,.....~~~ ~~~~~,.~..a \...:,~>.~..,f c-~~~~t'~V,i ~~~~~L~~~~~~~~~'~~~ " -~ ~''~ ~~.'.~?~~','', - L.~ —'~~~~. —-, ~ ~A'.'~ ~"~ -.,:,... ---. -,.,,; -,,~~~~~~~~~~~ —..1.~,........ — ~~ ~~~~~~.,~.......,, —-. -.......... Figure ~ ~ C11 9(e)L Imednc characteristics atr 88rc 98 and108 M =-,... ~ fo tes anena on 197 LihTuk ~~~~~ —-- ~ ~ ~ ~ ~ ~ ~ ~ ~ ~,::i —--;t -......:,.,.. / ~',' — ~-h-` —._ ~~ ~~~~-'' -'~. (e). — MS-2.. 25 -..'~".'. /.,?..-.:_. -....,..-,...,....'.''.'....2......."'...,...,. ~~~~~~~~,~,'. ~,',.'.~.' —-.- z.~.'",F~' ~ / " ~..'' " j'~,.,,~~~a,<..,.....,:~_....... fo-ir tes atenaso17 Ligh Trck (e) MS-20.ji`~~ i t:I ~\2

TABLE 3. PERFORMANCE DATA FOR TEST ANTENNAS ON 1978 LIGHT TRUCK. PERFORMANCE COMPARISON PARAMETER __ANTENNA TYPE STD ENT PRODUCTION EPL RP MS AM Sensitivity (dB/m) 0.76 MHz -68 -71 -66 -68 -74 1.10 MHz --- --- --- 1.60 MHz — _ Relative FM Sensitivity (dB) 88.0 MHz 0 - 2.3 - 4.8 - 1.8 - 1.1 98.0 MHz 0 - 0.2 - 5.6 - 6.1 - 8.1 108.0 MHz 0 - 0.7 - 3.7 - 3.3 - 3.5 Relative CB Sensitivity (dB) CH 1 0 - 8.0 - 9.8 - 9.8 -13.0 CH 19 0 - 8.0 - 8.0 - 8.0 -11.0 CH 40 0 - 8.3 - 9.7 - 8.3 -11.3 FM VSWR 88.0 MHz 1.81 2.89 4.83 5.26 3.50 98.0 MHz 2.03 1.23 7.16 7.36 7.75 108.0 MHz 1.47 2.32 6.87 6.54 6.06 CB VSWR CH 1 2.77 3.00 2.77 4.42 CH 19 1.63 1.05 1.40 1.13 CH 40 2.36 3.14 2.50 3.54 Isolation (mV) CH 1 95 300 274 164 CH 19 95 164 206 204 CH 40 123 245 245 136 AM C(PF) 0.5 MHz 68 95 68 91 98 1.0 MHz 72 100 71 95 97 1.5 MHz 66 92 67 87 98 AM Q 0.5 MHz 4724 402 630 286 155 1.0 MHz 2247 380 515 143 72 1.5 MHz 714 985 440 212 38 26

= 1u 02',%:i / Y 3' I 25 AAAA~~~~~~~~~~~~~~~~~~~~~~~~~~ MS20.F"~~~~~~~~~~2

__._ = 00 AAA MS- 20. 28 = 180~ Fiqure 10(b). Radiation patterns at CB Channel 19 for test and reference antennas on 1978 Van. 28

= 00'~'~ > —. ~';. I.74 Fiqure 10(c). Radiation patterns at CB Channel 40 for test and reference antennas on 1978 Van. CB Reference, —- EPL-20, **. RP-111-20, oooo D8UF-18B812-AC, AAAA MS-20. 29

20' j-4 F, -' / /7 - i ~~~~~~~ 35;IX\ ~ ~~ F'/ F>i K~~~'\~i /N x i~~~~1o Fiqure~~~~~~~~~ 11a.Rdainpten t8 i o etadF eeec antennas on 1978 Van. ____ FM Reeene EP-0 P112,00 8F18-C AAAA MS-20.~~~~~~~~~~~~~~~~~~~~~~~~~ 30\

___ = 1800 w-315 10 2 20 0'2 25"~~",",%- -, f -%oK /' 31

',-~,.~ ~ ~', -\x,',.', ~~~~~~~~~~~~~~~.1 ~2 —--- 25 ~ 5 20/ K~~~~~~~~~~~~~ K>' 25~~~~~L x \....,\ \\ 18'I....~.. ooo D8U- 1882-C:,, FM Reere35, - R1-'2 M- 2 A> 30 - - A A'~~~'='"I,, \\\ 1 ~~201 /~~~~~ ~~~`` i 16 Fiur 11c) Raito patrsa 0 ~ o etadF eeec anena on 198Vn FMr Reeene EPL20 RP112,k 000DU-1B1 C AAAA~~~~~~~~~~ MS20 32

:.... -. —Z i7 —-— ^-^^'i^, _...._. / II < 9'~ - (c)~l,.. ~:-..4-rA for tes a a on 97 V Aa. /, ( -- (c D 8..' 4.....................,,,.~';-;,,' ~.,',xL'?':'*: —:::~:':.~.".:". ~",".".".' ~4'~.-*'. ",:"-,''..": —.: —~ -'~'.Y..",''X.-',/.'. /'~-'.'-,"', "- ""-"~F~~ "."',," -'' -~" (a) EP- 2 0 b R 112, (c D8F!882.A Cd -0 33i

--- c,'.,...,,/..., -:? it',,,,,,,:., _,,,,,,;,,,,...-....I - - - I e ~.g t -.~ *yenlist. u'.':-,'''' - --. eIn A -o —' --'- ^-Z -- —' (c) (d) 34 * ~ 9.'.:>.""" ~ At:,..S-:'.. 4' -.-:'',.,-,.:-.... —-'- F -I. - -

=,-i -"- ---...:''...,.....-, - -.......~ ~, ~ - -^'.'- ^ —- _-_-. _w.-...... - a C",:u 5*.'" "l'.':':";'<, "' - "' -:."U -=:>::'-._.'._''.'".-"' _, + -. X' ^-.^^..::.-<^ ~ —...... -:. - ~:.-.r —--. K..:.-:.-.. —:: -..-.-. _ *-+?,______._. #/.^s^^^^.' ~.... 4'-''___ —-. —- " *t~tllt Few" *t{ I.! g~t _':...' |,*.,.......:...-..'...- - Figure 13(e). Impedance characteristics at 88, 98 and 108 MHz for test and FM reference antennas on 1978 Van. (e) MS-20. *~4v K l

TABLE 4. PERFORMANCE DATA FOR TEST ANTENNAS ON 1978 VAN. PERFORMANCE COMPARISON PARAMETER ANTENNA TYPE STD ENT PRODUCTION EPL RP MS AM Sensitivity (dB/m) 0.76 MHz -74 -68 -60 -68 -74 1.10 MHz --- --- --- 1.60 MHz. _ _ -- Relative FM Sensitivity (dB) 88.0 MHz 0 +1.7 -3.2 -2.7 -2.7 98.0 MHz 0 -1.0 -6.0 -6.0 -6.4 108.0 MHz 0 -0.2 -3.2 -4.6 -5.6 Relative CB Sensitivity (dB) CH.1 0 -8.3 -8.6 -8.6 -13.7 CH 19 0' -5.7 -8.0 -8.0 -10.7 CH 40 0 -7.5 -10.0 -10.0 -13.6 FM VSWR 88.0 MHz 2.06 4.62 5.29 4.94 3.34 98.0 MHz 2.09 1.44 7.77 7.00 7.74 108.0 MHz 1.58 3.00 6.29 6.18 5.91 CB VSWR CH 1 2.60 2.57 2.25 4.26 CH 19 1.46 1.07 1.28 1.12 CH 40 2.29 2.21 2.43 3.44 Isolation (mV) CH 1 236 410 320 195 CH 19 174 310 250 226 CH 40 198 174 245 177 AM C(PF) 0.5 MHz 68 99 68 91 98 1.0 MHz 72 93 71 95 97 1.5 MHz 66 91 67 87 98 AM Q 0.5 MHz 4724 182 630 286 155 1.0 MHz 2247 102 515 143 72 1.5 MHz 714 14 440 212 38 36

antenna is inferior in performance. 4.3. LTD II, Cougar/T-Bird These three cars have similar bodies, and the results shown apply to all of them. The actual test vehicle used was the Cougar. The radiation patterns and impedances are shown in Figures 14-17, and we note that the CB patterns shown in Figures 14(a)-(c) are all omnidirectional. Table 5 summarizes the results necessary for a performance comparison. The sensitivity of the unloaded antenna is inferior at CB and AM frequencies, but in other respects its performance is slightly better or at least equal to that of the other three antennas. 4.4. Bronco The results obtained with the test antennas mounted on a Bronco are shown in Figures 18-21 and in Table 6. The results indicate that, in general, the performance of the unloaded antenna is inferior to that of the other antennas. 4.5. Fiesta The results obtained with tested antennas mounted on the Fiesta are shown in Figures 22-25 and in Table 7. Our previous comments about the unloaded antenna apply here also. 4.6. Granada/Monarch/Versail 1 es These three cars have similar bodies and the results shown apply to all of them. The actual test vehicle used was the Versailles. Only the production model test antenna was used for this set of measurements, and the corresponding results are shown in Figures 26-29 and in Table 8. 4.7. Discussion Although it has been found that the performance of a test antenna depends on the vehicle it is mounted on, there seem to be no general 37

-___ = 00 = 10 ~ 7/4 — CB Reference, ---- EPL-60, *J RP-111-60, oooo"SOF-18B12-CE, AtAA MS- 60.,25 AAAA MS-60.~~~~~~~~~~~~~~~~~~~~~~-L'~...-~./",.~... ~ 3

= 00 ___ -, 180~ reference antennas on 1978 LTD II/Cougar/T-Bird. — CB Reference, ---- EPL-60, *30 RP- -60 oooo D80F-18B12-CE, N 39 39

= 00 Figure 14(c). Radiation Patterns at CB Channel 40 for test and.CB Reference, -- EPL-60, ** RP- -60, D80F-18B2-CE, 40 K25 35,, Fi u-'. R! --,..oooD0-8B2-E CB R ee ene — EL6'R-1-0 a,~a~~~~~~~~~~~~~~ ~ MS-60. ~ <'A' 25

C /Ki,, = 180~ Figure 15(a). Radiation patterns at 88 MHz for test and FM reference antennas on 1978 LTD II/Cougar/T-Bird. - FM Reference, EPL-60, ***- RP-111-60, D80F-18B12CE, AAtA MS-60. -K "' -/ N' a'~~~~~~~~~~'~~~~ 20'8~~~~~~i NOi -/7 ~~~~~' A'~~~~~ N' ~ C K'~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ / ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ = 18O

___ = 00 -- FM Reference,,'.EPL-60, *.*I RP-1-60, Z~~~ D80F-18B12-CE, 42 - 5-, —-~ —.1- 25 —. —--- 5s 3- 25 m 20 U 5 2 5 Figure 15(b). Radiation patterns at 98 MHz for test and FP reference a ntennas on 1978 LTD II/Cougar/T-Bird.

c Go ___ = 1800 Figure 15(c). Radiation patterns at 108 MHz for test and FM reference 43 43

<^~~J'..,t.......-.-._.::.., (a) (b) w-tlm, m 4t FT "pitt..,' -, m,, -i -—'-2*"?.'~'~:^2-' - ".H...'O. _. 1" -_ (a) EPL-60, (b) RP- -6, (c). D80F-18B12-CE, (d) MS-60. 44'C-'.::',> -''C -..-' -- -.-.. 44

*., —.,,,.....*^ *-. 7777=^ ^^' *...... - 7'^- <?^ ^ ^ ^<- -~~~ —~~'-~~'~.....1:^^M:-..-' O "- m- SW -L ( a)' EPL-6'3'. b RP'.-11"16.0 —-- -—, -.(c.' ". " C ( MS6 45. ~.:~. ~.<'.~-. "' " "":'~"' ~',-~~ ~2C:":-L"-~:.:,>;. /.'.'.'.'..'....:~-':.'.'.'.':~'.'~'." ".,''~f. ".' "~ t''''.~'~ ~'''''""''""'''...~~';"~""''"/~",~~.... ~'~'"...."'".........'~ " ~ ~"':'''.C.' ~:'.-,~ >.::':..'<::.':~':::-~ -:'-',:~-:.'~,'-~.':2~''.~'>"';:~:,.-..> -~:: i.'.:~.'::: — ~'" ~"~.'-~-'~_.: ~ ~.:- ~.:/~,,- ~~,..,.,' -..0-<,...,,.~ -::-:-.:~..::._~:_>~..-.-..-~,-. -II"A SW(,.7 7. jIt~~~~~~~~~~~~~~~~~~~~~~:',:'.:.-~_...'' -' "'L-': —~.. ~'~..................: _.. _:~~~~~~~~~Ji -..................'..'.'..:'.~.'.:', __' ~_,:_ _:~' ~ _~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~_- pi. ~...:.......

TABLE 5. PERFORMANCE DATA FOR TEST ANTENNAS ON 1978 THUNDERBIRD/LTD II/COUGAR. PERFORMANCE COMPARISON PARAMETER ANTENNA TYPE STD ENT PRODUCTION EPL RP MS AM Sensitivity (dB/m) 0.76 MHz -66 -67 -64 -67 -72 1.10 MHz --- --- 1.60 MHz --- --- Relative FM Sensitivity (dB) 88.0 MHz 0 -2.5 -1.3 -2.0 -0.3 98.0 MHz 0 -1.0 -4.8 -7.0 -2.6 108.0 MHz 0 -4.3 -8.0 -10.0 -7.9 Relative CB Sensitivity (dB) CH.1 0 -3.1 -3.1 -7.1 -8.2 CH 19 0 -3.3 -2.2 -5.4 -7.9 CH 40 0 -5.8 -3.6 -6.9 -11.4 FM VSWR 88.0 MHz 1.36 3.65 2.27 5.21 2.02 98.0 MHz 1.33 2.91 10.38 9.21 2.39 108.0 MHz 1.45 5.21 12.67 13.00 6.86 CB VSWR CH 1 2.58 2.16 2.63 2.50 CH 19 1.25 - 1.22 1.27 1.15 CH 40 2.47 2.13 2.69 2.14 Isolation (mV) CH 1 350 470 420 147 CH 19 190 310 295 192 CH 40 350 150 410 180 AM C(PF) 0.5 MHz 1.0 MHz 1.5 MHz 0.5 MHz 46

= 180~ Figure 18(a). Radiation patterns at CB Channel 1 for test and reference antennas on 1978 Bronco. CB Reference, ** * EPL- 20, o:o RP-111-20, oooo D8TF-188812-AD AAAA MS- 20 47

0 -X = 180~ Figure 18(b). Radiation patterns at CB Channel 19 for test and reference antennas on 1978 Bronco. CB Reference,.... EPL-20, a=aRP-lll-20, oooo D8TF-18B812AD AaA MS-20 48

I 00 = 180~ Figure 18(c). Radiation patterns at CB Channel 40 for test and reference antennas on 1978 Bronco. CB Reference,.... EPL-20, oa0Rp-111-20 oooo D8TF-18B812-AD AAAA MS-20 49

= 180~ Figure 19(a). Radiation patterns at 88 MHz for test and reference antennas on 1978 Bronco. X/4 FM Reference,.... EPL-20, ==: RP-111-20, oooo D8TF-B812-AD A~AA MS-20. 50

= 180 ~ Figure ]9(b). Radiation patterns at 98 MHz for test and FM reference antennas on 1978 Bronco. ---- t/4 FM Reference,.... EPL-20,::~ RP-111-20, oooo D8TF-18B812-AD 51 Fiur 1().Raiain atensat98Mz ortstan/F efr5c

antennas on 1978 Bronco. A/4 FM Reference,.. FM Reference, =: o EPL-20,.... RP-111-20, oooo D8TF-13B31 2-AD 52

7,.-L- - -' -.-.., -......... --- -- - ~....,, _Lr.-~~Jn~M —y......:- - _-:....,,! -----; ---'L-, t- - - - - Fiure 20. Impedance characteristics at CB Channels 1, 19 and 20frequencies for test antennas on 1978 Bronco. (a) EPL-20, (b) ()RP-111-20 () D8TF-1B812-AD (d) S-20 ~,a)iii ~.....,,.-.,'.:'.:,:~-=':....-,.'~"t-',,'~..'...." " "......"''"~.53"' "

oh's' -—'-' *'-,-, ad a' * ~' <- --- --- ^,.....-.-N'(S -— 4-.-... -:' i,', —- —. n e.,. c-' w-^^^^.-*{tzf Yo u *Z~t Pnt~ al9^'^y'.-* e"::' bu:'.'. -' (a) EPL-20, (b) RP-111-20, (c) D8TF —18B812-AD., (d) MS-20, 54 v...,.: ~,,'.-....::~.:.:.~:~:; -.. it m -.'....,, "'....,";'~:-~z~'."t'~:~"-"':.'.'.;"','. -' — ~i"'-? ~, -. ~.~(a)(b

-i -. ~','*.". l~'.. L- j,-..-'m t-~-: -~' — -'- - -, e,' tt Ui,' -,,,,,,,, n — n- — mil-'f; ~ -- f'' _.,, -4-t- 7, - l -. Figuremutt,l~ m a 8 "n 1-8 M. — -t-:-,. (e) 55' -.. -.-et- -: —-'t n.- 17 B. — - "..St "if * -Solt MITI" "M "at:-........ A...... 1 --:'-::.iii~iii-:: ~ —:~......' —- "-, rA~~~~~~~~:.....'. of ~ ~::::::...s

TABLE 6. PERFORMANCE DATA FOR TEST ANTENNAS ON 1978 BRONCO. PERFORMANCE COMPARISON PARAMETER ANTENNA TYPE STD ENT PRODUCTION EPL RP MS AM Sensitivity (dB/m) 0.76 MHz -61 -66 -61 -63 -69 1.10 MHz -69 -74 -69 -71 -78 1.60 MHz -81 -86 -80 -81 -86 Relative FM Sensitivity (dB) 88.0 MHz 0 -1.0 -4.5 -3.0 0 98.0 MHz 0 +2.0 -7.0 -3.5 -4.5 108.0 MHz 0 +1.0 -5.0 -5.0 -5.0 Relative CB Sensitivity (dB) CH 1 0 -11.0 -8.0 -11.0 -15.0 CH 19 0 -9.5 -7.0 -10.0 -12.0 CH 40 0 -10.1 -8.5 -10.5 -14.0 FM VSWR 88.0 MHz 1.88 2.64 8.47 4.60 3.09 98.0 MHz 1.93 1.19 13.0 6.0. 6.85 108.0 MHz 1.76 2.02 8.0 5.93 5.50 CB VSWR CH 1 2.44 3.28 2.65 3.77 CH 19 1.38 1.1 1.38 1.14 CH 40 2.44 3.13 2.54 3.43 Isolation (mV) CH 1 72 320 280 172 CH 19 105 170 200 218 CH 40 100 285 230 160 AM C(PF) 0.5 MHz 68 95 68 91 98 1.0 MHz 72 100 71 95 97 1.5 MHz 66 92 67 87 98 AM Q 0.5 MHz 4724 402 630 286 155 1.0 MHz 2247 380 515 143 72 1.5 MHz 714 985 440 212 78 56

30 5 = 180~ Figure 22(a). Radiation patterns at CB Channel 1 for test and reference antennas on 1978 Fiesta. -- CB Reference, a a a EPL-20,.... RP-111-20, oooo00 D8TF-18B812-AD, MAA MS-20. 57

=00 = 180~ Figure 22(b). Radiation patterns at CB Channel 19 for test and reference antennas on 1978 Fiesta. — CB Reference, o:aEPL-20,.. RP-111-20, oooo D8TF-18B812-AD, ~aea MrS-20. 58 30 5 C 1 20I 25

= 180~ Figure 22(c). Radiation patterns at CB Channel 40 for test and reference antennas on 1978 Fiesta. CB Reference, o o aEPL-20, -.. RP-111-20,.ooo D8TF-18B812-AD. 59

___= 180~ Figure 23(a). Radiation patterns at 88 MHz for test and reference antennas on 1978 Fiesta. -/4 Reference,.... FM Reference, a: a EPL-20,.... RP-111-20~ oooo D8TF-18B812-AD, a^AA 1S-20. 60

= 180~ Figure 23(b). Radiation patterns at 98 MHz for test and FM reference antennas on 1978 Fiesta. -x/4 Reference, FM Reference, = o= EPL-20, **.* RP-111-20, oooo D8TF-18B812-AD, AAA MS-20. 61

I = 1800 Figure 23(c). Radiation patterns at 108 MHz for test and FM reference antennas on 1978 Fiesta. x/4 Reference, FM Reference,a = =EPL-20, * —- RP-111-20, ooooD8TF-18B812-AD, AAAA MS-20. 62

' —',"-'-.- — A-" I.- 4 F ur*',',.2'*'4,.~. — d-.-_ ch ra te is. — ics....'-'.-.. n.....-. -. a...: (a),, —2 - -— 2 — --,,,,, (d'm NM II II "''**^*^*-,/^'*^\';^^ ^ ^;;^^ -' --' I''l-SO'';*/ ".' X —f;<'-'.',.. F.gure. 4.. meac'.t...n-.,, 9- 4b) for the test antennas on 1978,Fiesta. -[''- A(c) (d)~~~~~~~~

::.:.:_:L+: T'-: T —-"'.>' "...._ -'-L:::~- -:,-..= - -- - *. I -. —:..........s 4. 4. #'NX^;7. "~'l.^1-I (c) (d) " —-- "/-'- \,-'-' /-,'''. 64 ---. - —:, —.. ~U ~ ~ ~ ~ ~ ~ ~ M n..'I'..,.'...;..: —-:.~x_-..,:..:-. -, ---.B 2,-'<.-.'-.:.,.-:~-~.... —.::,'x.-.'.:-:1.-..',..'::7' - m. ~.":.I... 4.:.'~.. (Coninue on'- next.. page),"- -:'-m''.'',.... —r-".',.':. >:.'/.~'.,,....~......'.'.. 64Z':~'

~a-*H' ut UiE ", r',;... —:;. *" # _.-::. ". s e a d,. i j.'; - -sj" *", ~",. 4',,~:<. _:..-'.- -.._.. - -~ ~ _ —^,-:.... ~:;...... ~'' *- * r,, (e)- (e),: T ~'i, F R frne 7..........'...... i^:'6 "3'^ -^ ^ ^''""^ "y ^ ^ ^ ^ ^'-'-'- 3 Figure 25e) I ca t s a 88. 98 a ~0 M'-.or it. () R(e)frne ~-.........-~''' —-— ~ —'-" —:-"-. —'"': test antennas on"' 1978 Fiesta.',-~"~.~..:"'_ ~' ~ -~:-:___~ — _~ ~'-'. ""~' (e). FM, Reference. >,,.'I: - 65 ~ ~ ~~~-.~....-.,..> ~,..~.,/. ~~

TABLE 7. PERFORMANCE DATA FOR TEST ANTENNAS ON 1978 FIESTA. PERFORMANCE COMPARISON PARAMETER ANTENNA TYPE STD ENT PRODUCTION EPL RP MS AM Sensitivity (dB/m) 0.76 MHz -61 -64 -61 -63 -70 1.10 MHz -70 -74 -70 -73 -78 1.60 MHz -81 -84 -80 -81 -86 Relative FM Sensitivity (dB) 88.0 MHz 0 -1.5 -4.0 -3.5 -0.5 98.0 MHz 0 0 -5.5 -4.0 -3.5 108.0 MHz 0 -5.0 -5.5 -6.5 -1.0 Relative CB Sensitivity (dB) CH 1 0 -9.0 -9.0 -10.0 -14.0 CH 19 0 -7.5 -8.0 -9.0 -11.0 CH 40 0 -9.0 -9.0 -10.0 -14.0 FM VSWR 88.0 MHz 1.39 2.66 8.11 5.96 2.66 98.0 MHz 1.39 1.11 11.0 5.96 5.86 108.0 MHz 1.58 2.21 7.91 9.75 5.13 CB VSWR CH 1 2.52 3.14 2.58 3.46 CH 19 1.32 1.15 1.36 1.07 CH 40 2.22 2.63 2.:7 3.45 Isolation (mV) CH 1 400 225 172 270 CH 19 215 160 200 235 CH 40 235 270 135 155 AM C(PF) 0.5 MHz 68 95 68 91 98 1.0 MHz 72 100 71 95 97 1.5 MHz 66 92 67 87 98 AM Q 0.5 MHz 4724 402 630 286 155 1.0 MHz 2247 380 515 143 7 1.5 MHz | 14 985 440 212 38 66

= 180~ Figure 26(a). Radiation patterns at CB Channel 1 for test and reference antennas on 1978 Granada/Monarch. -- CB Reference, ----- D8DF-18B812-AC. 67

!, 3 \ I, >' 1' =180~ Figure 26(b). Radiation patterns at CB Channel 19 for test and reference antennas on 1978 Granada/Monarch. CB Reference, - D8DF-18B812-AC. 68

I Figure 26(c). Radiation patterns at CB Channel 40 for test and reference antennas on 1978 Granada/Monarch. — CB Reference,.. D8DF-18B812-AC. 69 Q7,~~~~~ 35 01 Fiqre 6(c. Rdiaionoat 30n atC'hne 0frts n eeec

W-15 "~~IS~~~~~~ ~ I I AI 25 = 180~ Figure 27(a). Radiation patterns at 88 MHz for test and FPI reference antennas on 1978 Granada/Monarch. - FM Reference,.. D8DF-18B812-AC. 70

= 180~ Figure 27(b). Radiation patterns at 98 MHz for test and FM reference antennas on 1978 Granada/Monarch. - FM Reference,.. D8DF-18B812-AC. 71

= 00 = 180~ Figure 27(c). Radiation patterns at 108 MHz for test and FM reference antennas on 1978 Granada/Monarch. -. FM Reference,.. D8DF-18B812-AC. 72

-'~ 4'" ""'.-'' ""' a'- N " " S. U a a4 4..~~~~~~~~~,~~~- -"' —- -- - IV~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~..'-~ ~... — 7,-;-:.\-=~-~_',:L >>.-i~'.-*.~ —,r +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~lf a-:, a'. —-....~.,? t.. Jut...... t.........'....~~,.__L_~~,, ~ ~~tg ~.~~~~~- -' — - - ---— I 7 ~:!,j ----' —.._,'-. ~ ~ ~ ~ ~ ~ ~ ~ I:.~ ~(. --— ~: Lt.~_ r / -~ i Z~~-77: 1 -~." ~-~ L-4-..........~~~~~~~~~~~~~~~~~~~'.,.7:..,,~ *-~'-i ~ ~~~~~~~~~~~~~...:...,..... -,. r~ er ~.., /..,. ~.. 4/ V' ""~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~'~~ -,~..:~, -,4,$ /...~....,''~. ~,:,, 41p~~~~~~~~~~~~~~~~~ - - L~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~i (28) -~~~~~~~~~~~~~~'...,'.'','.''.N-'~.-.:i:%:-.,~ 4-~~~~~~~~~~~~~~~~~~~~4 a~~~ a'~~~~~~~~~~~~~~~"."'"'....." - -'''."'.'"'-4 —.- i -m,'-C~~~~~~~~~~~~~~~~~~ ---. —-~', ~~~~~~nt,, r -U'~a —.'/'.: > —-—::. ~:>~~_,~.,~-~e. D8DF-~I 1 8B12-G.....7 -— ~~~~~~~~~~~~~~~~~~~~~~~~~~.%,-i::~.-...'._.b...,',:~., a. ~~~~ —4-:,-'.t.-L"-', - -~.,~.f-. ~.. I~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~~~~~~~~~~~~~_.~ — ml' fI o" dit-M: P11 f&Uou I. *f~~~~'Ipednc c aterist30 —fi c at CB C anl l,1 ad4 frequencies for -t h e te st antenna on 1978 Granada/onarch. DSDF-18B812-AC. 73 ----— Z

-? l- B4 - " - -,,,,, * - -.. - - -'-... —'' - -. |'- -~-'' i....' —' -S M:-J: -a — -, —--------............I ~~~~~~~~~~~~~'- -? (a ) D8DF-18B812-AC, (b) FM Reference. 74...............,, ~'~,.'., ~, ~,...~,~.-.-.m —.~ >'.' 2, -~ ~ ~'x''.. i:''~""~'": ~. _-:~ —:.:~.'i.-~.:. -,'..",

TABLE B. PERFORMANCE DATA FOR TEST ANTENNAS ON 1978 GRANADA/MONARCH PERFORMANCE COMPARISON PARAMETER ANTENNA TYPE STD ENT PRODUCTION EPL RP MS AM Sensitivity (dB/m) 0.76 MHz -64 -68 1.10 MHz.... 1.60 MHz \...._. Relative FM Sensitivity (dB) 88.0 MHz 0 -1.78 98.0 MHz 0 -1.10 108.0 MHz 0 -3.60 Relative CB Sensitivity (dB) CH 1 0 -9.70 CH 19 0 -9.10 CH 40 0 -9.60 FM VSWR 88.0 MHz 2.71 1.20 98.0 MHz 1.79 2.67 108.0 MHz 1.66 5.71 CB VSWR CH 1\ 2.43 CH 19 1.19 CH 40 2.04 Isolation (mV) CH 1 \315 CH 19 172 CH 40 250 AM C(PF) 0.5 MHz 96 97 1.0 MHz 102 103 1.5 MHz 93 96 AMi Q 0.5 MHz 1635 507\ \ 1.0 MHz 1553391/ / \ / 1.5 MHz 1697 232 / \ / \ / 75

rules by which all the performance criteria of the antenna are affected by the test vehicle. On the basis of the results discussed in the previous sections we make the following comments on the general performance of the various test antennas: (i) AM Sensitivity The test vehicles have appreciable effects on the AM sensitivity of each test antenna; except for the van, the vehicle can cause a total variation of 2 - 4 dB in the observed sensitivity. When mounted on the van, each antenna maintains its largest sensitivity and the EPL antenna then has a maximum sensitivity of 12 dB. The MS antenna has the poorest sensitivity with all vehicles. In order of decreasing AM sensitivity, the antennas are: EPL, RP, Production and MS. (ii) FM Sensitivity The vehicle effects cause a maximum variation of 5.5 dB in the FM sensitivity of the MS antenna, and variations between 2-3 dB for the other antennas. The production antenna has the largest FM sensitivity. All the test antennas except the RP ha'-e the largest sensitivity when mounted on the LTD II. (iii) CB Sensitivity Vehicle effects may cause a maximum variation of about 5 dB in the sensitivity of each antenna. The lowest sensitivity of the MSantenna is about -12 dB; the other antennas have comparable sensitivities, the least value being about -9 dB. All antennas have largest sensitivity with the LTD II. (iv) FM VSWR The production antenna maintains a VSWR < 3 with all vehicles; the other antennas generally have large VSWR (>4) with all vehicles. The vehicle effects on the VSWR are insignificant. (v) CB VSWR The test antennas, being tuned to CB channel 19, maintain VSWR < 1.5 at channel 19 with all vehicles. The vehicle effects on the VSWR are insignificant for antennas tuned on individual cars. 76

(vi) CB Isolation The production antenna has the best isolation characteristics. On the basis of the above comments, and the results discussed earlier, it is concluded that of all the antennas tested the Production antenna has the best, and the MS antenna the worst, overall performance. 77

V. REAR TRI-BAND ANTENNAS WITH IN-LINE CAPACITORS The short loading coil (SLC) power tri-band antennas using a padder capacitor at the AM/FM input line of the radio (Figure 5) is compared with production antennas with padder capacitors in the splitter box. Some of the production series (i.e. D-series) antennas use conventional loading coils to obtain better CB-isolation characteristics, and have the CB and AM/FM branches within the splitter box shielded from each other by using a metallic barrier A —-A as shown in Figure 5. The latter are referred to as improved production series or improved isolation antennas and will be denoted by an appropriate D-number without padder capacitor. The present chapter discusses the results obtained with SLC and improved production series antennas mounted on a variety of 1978 model cars. The test vehicles were Lincoln Mark V, Lincoln, Cougar and Versailles. 5.1. Mark V Figures 30 and 31 show the CB and FM band horizontal plane patterns obtained with SLC and improved production series antennas, along with the corresponding patterns for the standard antennas. As seen from Figure 30 both test antennas perform similarly in the CB-band of frequencies, although the improved production series antenna does appear to have slightly less sensitivity at the highest CB channel frequency. The improved isolation antenna has less sensitivity than the SLC antenna at 88 and 98 MHz (Figures 31a and 31b), but more at 108 MHz (Figure 31c). The difference is due to the short loading coil used, not because of the capacitor. Note that at both CB and FM band frequencies the two test antennas have sensitivities less than the corresponding standard antennas. The impedances of the two antennas at CB frequencies are shown in Figure 32. The FM band impedances of the 78

____ = 00 180~ Figure 30(a). Radiation patterns at CB Channel 1 for SLC and reference antennas on 1978 Mark V. CB Reference,.. D8LF-18B812-AC with padder capacitor D8LF-18B812-AC without padder capacitor. 79

Figure 30(b). Radiation patterns at CB Channel 19 for SLC -- CB Reference, D8LF-18B812-AC with padder capacitor, 80 Figure 30(b). Radiation patterns at CB Channe el9 for SLC A d. — e-e-20 2n5 30 CnnIa mm 97 0. C8 efee~c,...DSL-]SS]-A~wit pade caac35r.... D8LF-]~~~~~~~K 3012 A withotpde aait 80~~~~~~~~~~~

00 uJ-15, i~~~~~~~~~~~~~~~~~~0?~~~~~~ I 20 KX~. I K~~~~~~~~~~~~~~ 25 30 F r 0 R i o t n C C n 0 r:~~~~~~~~ I< / /` ~;~,O,*i~ CT1X~~_Si C~iP~XmT~iw 25 20 AKfl/~'//X/XX~ _ _ _ _ = 1 0 Figure 30(c). Radiation patterns at GB Channel 40 for SLC~~ and~~~~~~~~~~~~~~~-~Li reernc antennas on 1978 MarkV GB~~~~~~r Reeene D8Lf-1B12A wihpde cpctr *~XX~~KX... D8F1B2A withot pade capaitr 81

00' ~~~~~~~~~~~~~~~ -1~ I Ui 20 0 25 20 215 30 25~~~vy- 2~01 —— 1 ~~~~~1 ~ ~ 1 25~ fil I~~~~~ /6<~~~~ I~ ~~~~~~~~ 2 L< ~ ~~~~~~~~~~~ / 1800 Figure 31(a). Radiation patterns at 88 MHz for SLC and FM re-ference antennas on 1978 Mark V. FM Reference, D8LF~~~~~18B81-AC w~~ithpde cpctr D8L-1881-A wihu padrcpctr.i~~~~~~~~8

_= 0 0 /~~~~~~~~ K' X'K /'', i' 2;~ ~ ~~~~5< /~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ K~ - -= 1800 Figure 31(b). Radiation patterns at 98 MHz for SLC and FM reference antennas on 1978 Mark V. FM Reference,...D8LF-18B812-AC with padder capacitor,.... D8LF-18B812-AC without padder capacitor. 83

0 20 302 0 - oii i i < 25K i I~~~~~~~~ 0 / 5 Fi 5ure 312c) —Radiat30 35ters a 115Mz 10 LCan 35 rpfprpnce antenas on 1.978 Mark V 25 N'K X/~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~;C~~~~ -=10 Fiur 31c) Raito atrsa 0 I o L n FM~~~ reeec anena on17 akV FM ~ ~ ~ i Reeec, DL-882ACwt adrcpctr D8F1882A witou pade capacitor.C/ X/ I \ r~8

'-.411,,....... _ - L —------— ~ -;-' IT 7~J.'A#.X-A37.I Y - I - - -~- I I, -..I -.' ".." AI....' O..... I V5'A~~~~~~~~~~~~~~~~~~~~~~~J (a) (b) I' -'A~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~`- 9, 9 K~\\ *c~ \' C.~~ F -~-'~~................. t~~~~~~~~~~ ~-~< ~ - I-~ — C'A,& 4' * -..1. Figure 32. Im.Dedance characteristics at GB Channel 1, 19 and 40 frequencies for the SLC antennas on 1978 Mark V. (a) D8LF-18B812-AC with padder capacitor,. (b) DLF-~l8B812-AC without padder capacitor. 85~~~~~~~I/

AM/FM standard and the two test antennas are shown in Figure 33. 5.2. Lincoln The CB and FM-band horizontal plane patterns obtained for the test and standard antennas are shown in Figures 34 and 35. Observe the CB sensitivities of the two test antennas in the 90~ and 270~ directions of Figures 34(a)-(c) and compare them with those in Figures 30(a)-(c). It is found that the directions of minimum sensitivity are interchanged. It thus appears that reduced sensitivity occurs along the 90~ - 270~ direction, with the minimum occuring on the side where the antenna is located. The results of Figure 34 indicate no significant difference in the performance of the two antennas at the CB frequencies. At FM band frequencies the SLC antenna appears to have equal or more sensitivity than the reference antenna (Figure 35). The improved isolation antenna is found to be less sensitive than the SLC antenna at 88 and 98 MHz (Figure 35a-b), but at 108 MHz both antennas have approximately the same sensitivity, larger than that of the reference antenna. The corresponding impedance results are shown in Figures 36 and 37. 5.3. Cougar Figures 38-41 show the appropriate radiation patterns and impedances for the two test antennas mounted on the Cougar. Figure 38 indicates that the SLC antenna has less sensitivity than the improved isolation antenna at all CB freqencies. At FM band frequencies the improved isolation antenna appears less sensitive than the SLC antenna. 5.4. Versailles Results for the test antennas mounted on the Versailles are shown in Figures 42-45. The CB performances of the two antennas are about the same (Figure 42). At 88 and 98 MHz the improved isolation antenna is somewhat less sensitive (Figure 43a-b), but at 108 MHz the two antennas have about 86

7-7 ~^<:::^^^., —'^^^^lo^^',':' ~.~,,._,., -: - *~91 t -.-. —-.?-...:,1~/~~~~~~" ~',t~'.~'.o ". - m P-.",.s. n, ".;~ w:.'Z..:*'... ^.';'.'..'..:'..: i...... " - -"..-...<'.'.'.J."<..' (a) (b).- cad.der-".'.I'.ap cior (c) FM:ef.rence..... SLC and F reference antennas on 1978 Mark V. padder capacitor, (c) FM Reference. 87:yj ~ ~ ~ ~ ~ ~ ~ ~ r- r f t~-~ -~ W11 ~ -CI:-r — c- f" ~~~~~~~s ~I

= 180~ Figure 34(a). Radiation patterns at CB Channel 1 for SLC and reference antennas on 1978 Lincoln. - CB Reference, D8VF-18B812-AC with padder capacitor,.... D8VF-18B812-AC without padder capacitor. 88

= 180~ Figure 34(b). Radiation patterns at CS Channel 19 for SLC and reference antennas on 1978 Lincoln. CB Reference, --- D8VF-18B812-AC with padder capacitor,.** D8VF-18B812-AC without padder capacitor. 89

\~t7 \Il' -~-til 5'~ " "" ~~~~~~~~~~~~~~~~~~~~~~~~-... ICI I 0.,1, w I N.7 < 7 IL,~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~\ -.',, / ~X / \ ~. i I~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ \~~~~ ~ ~~~~~~~~~~~~~ \; \ ~~~~xr~~~~~ ~ ~35 3o,-~5~ —2 15r -L /, \,, ~ %~`` -15, %~~~~~~~ d referenc anennas o7c GB Reference,...D8VF-18B81 2-AC wit~h padder capaci tor,.... D8VF-18B812-AC without padder capacitor. 90

=00 /~~ ~ ~ \ - ~~~~~~~~~~~~~~~~~~~~~I r ~~~~~~~~5 A' i~ ~ ~~3 - <I~~~~~~~~~~~~~~~~~~~~~~~ A' /'1 9 Fic~~~~~~ure~ ~ ~ 35a Raito atrs t8 o L and~ reeecanenso198Lno. FMRfrne 8F-882A ihpadrcoctr D8F1B8A withu pade caaitor. \: I~~~~~9

30 X ~ ~~~~~~ \\ -1Oo,~~~~:, Figure 35(b). Radiation patterns at 98 MHz for SLC and reference antennas on 1978 Lincoln. -— FM Reference,...D8VF-18B812-AC with padder.capaci tor,...D8VF-188812-AC without padder capacitor. 92

=00'I " I~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 20~ ~~~~~ 1 K~~~ /~ /NNY i I~3 i$ A.. ~ ~ ~ ~ ~ ~ Y 35,i ~ 30~-~-425 24 15 10 /~~~~~~~~~~~~~~~ /~ ~ ~~177L 20:i~~~~~~~~~~~~~~1 - nO and reference antennas on 1978 Lincoln~~~~~~~~~~~, FM Reference, D8VF-18B8124C with padder capacitor,~~r....~ D8F1B82A wihu ade caaitr 93

' ~.-'-"-~ —'~ ~ ~ —-.-"% -' C ~ ~ ~ ~ ~'.' ~.,.. --— Z ______ 71-%t- Il" A~~~~~ ~~~ tz-.Z~',,-:'.,':"g' " —. ~ --— >''~;-..'. -,%..N K;' 4<.' l~~ltll igll I~- llte_ ~~~~~~~~~~~~~~~~+ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~'" ",' ~-` -' ~-:... ~"'- "'- "'.. *`~~~ ~ ~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~.......,....t ~ e..;.,:- -.. -:- # ~,, 4. "V~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~',~~k~~ \ c i *1 ~~I' -'' —-~~~~~~~~~~ ~-'-'',,,'>'.;, -.:,!......'.,...:,:.,~~ ~ ~ ~ ZF'..Z-X,''."/:">.."';,.'~''..: ".'~~ Figure 36. Impedance characteristics at CS Channels 1, 19 and 40 for the SLC antennas on 19'78 Lincoln. (a) D8VF-18B812-AC with padder capacitor, (b) D8VF-18B812-AC without padder capacitor. 94

r~ Sy _ l _ \ *~K X,~ — _. _ _ m, - -- _ _.- - --' —---., v. |.'''-......'\^ r. *\ - /- x- - - 2 / = % "%^^^^^C^^ "''^fii^S^^''..,._.__._ —_., -*;-. ~ _ ^ _..._., (C)Cl~~~~~~~ ~ ~~b (a) D8Vf-18B812-AC with aadder caacitor (b) D8VFA18B812-AC without ______*. ~::': 4.'4~~, Fgure 37. Impedance characteristics at 88, 98 and 108 MHz for the SL and F efeence antennas on 978 Lincon padder capacitor (c) FM Reference. 95.16111 - AUIIMM~oi-~ sy'lPU u oy ~ ~ ~ ~ ~ ~ ~ ~ mrirruc-c_ u u ----------— ~rlr 4 *r-l ~~ct ~ -u —-- -i —~ —— ~~-I It;.t~l t t.- I

reference antennas on 1978 Cougar. 30 - - CB Reference,.. D8SF-18B812-AA with padder capacitor,.... D8SF-18B812-AA without padder capacitor. 96

w15 00 25,z~U x< 20 30 25~~~~~3 0180 Figure 38(b). Radiation patterns at CB Channel 19 for test and reference antennas on 1978 Cougar. GB Refrence, D8SF- 18B812-AA with padder canaci tor,.... D8SF-18B812-AA without padder capacitor. 97

00 *15 3 S Fiaure 38(c). Radiation patterns at CB Channel 40 for test and reference antennas on 1978 Cougar. -- CB Reference, — D8SF-18B812-AA with padder capacitor, **.. D8SF-18B812-AA without padder capacitor. 98

00 I 5 80 F5 Fiur 30() Raditio paten at 20Mzfrts adFeeec antennas on 1978 Cougar. 1 FM Reference,...D8SF-!18B812-AA with padder capacitor,.... D8SF- 18B812-AA without Dadder capacitor. 99

21 25 3 25 0 1 I 3I ____ = 180~ Figure 39(b). Radiation patterns at 98 MHz for test and FM reference antennas on 1978 Cougar..... D8SF-18B812-AA without padder capacitor. 100 25~~~~~~~~~

= 00 215 __ = 1RO~ Figure 39(c). Radiation patterns at 108 MHz for test and FM reference antennas on 1978 Cougar. FM Reference,... D8SF-18B812-AA with padder capacitor, *.*.* D8SF-18B812-AA without padder capacitor. 101 30~~~r5' 15: \~~~~=lO Figure 39(c) Raiaio patrsa Mzfrts ndF eeec antennas on 1978 Cougar.~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ FM~~~~~ ~ ReeecDS-88 A wit pade caaitr D8SF-18B812-AA~~~~~ wihu odrcpctr 101

.....~~A<~ /,~...........~:'L,, ~~~~~~~~~~~~~~~~~~~~..,. "4 cc~~~~~~~~~~~~~~~~~~~~~~~~ (~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~a) I~~~~~~~~~~~~~~~~~~~~~ K,~ 40 ~ ~ ~ ~ ~ ~' NN. IL C (a) ~~~~~~~~~~~~(b) Al ~ ~ ~ ~ N ~ 41-:7 ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~~~~is~~~~~~~~~~~~~~~~~~.... ---:: ~~..-.::-:-__ ~:..'-:-,, S L~~~~~~~~~~~~~~~j It, ~ ~ ~ ~ ~ ~ ~ ~ ~.,.. i~~~~~~~~~~~~~~~~i j i.,_Cc~~~~~~~,* ~,,','.'',,- >~,-.-."-Z-,','..."'~, " ~ ~,4 —- /,J 7~~ Ii;t ii`i i - L Figure 40. Impedance characteristics at CB channels 1, 19, and 40 frequencies for test antennas on 1978 Cougar. (a) D8SF-18B812-AA with padder capacitor (b) D8SF-18B812-AA without padder capacitor. 102

4"-(UtssttlUI&F ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~,,' j' ew YU*'; -*uw.." "A. o lot -fair -fllli^Slll^ -X = --- " i -,;' -. - ~-'- -- -. - - --..->.,'.w-*. -/ - i t N'U, X -.'.... Figure 41. Impedance charactistics at 88, 98 and 108 MHz for test and;. —..(PE) —'.... 103 --— _.......~.... c r-88-'AA witou p a (c) FM reference (PE)"-.-'~'.'..-"'-' —-- -. "-,'' —'-.,'"' " -'''''''~''''' ~'''*' " ~'-~'..,L ~ -F'-~: "/ r*.'", ~x'.''-:.'..".'':~":';/.'y10/~3.'.~

-= 180~ Figure 42(a). Radiation patterns at CB channel 1 for test and reference antennas on 1978 Versailles. --— CB reference,.. —D84F-18B812-AC with padder capacitor, * -- D84F18B812-AC without padder capacitor. 104 i Q00~~1 Figre 2(). adatin pttrnsatCB hanel1 fr estan r35r onra =n~mnn — xn17 nv=1n

___ = 00', _ 180~ Figure 42(b). Radiation patterns at CB channel 19 for test and reference antennas on 1978 Versai1 1 es. CB reference,.... D84F-18B812-AC with padder capacitor,..... D84F18B812-AC without padder capacitor. 105

30 /~~~~~~~~~~~~~ 35 I ~ ~~~ N'a I~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ a~~ 30 i~~~~~4 A'i ~I 5 / <p,',, I! % a 20 x 7/ a~~~~~~~~~~~~~~~~~~~~~~~~~~ ____ 1800 irT 106

= 180~ Figure 43(a). Radiation patterns at 88 MHz for test and FM reference antennas on 1978 Versailles. FM reference, s. D84F-18B812-AC with padder capacitor, *.... D84F18B812-AC without padder capacitor. 107

II K~~ I' 20 antennas o n 1958 Vers.1 -~~~~~~~~~~~~ K 1882A ihu ad r caaitor 108 10-~e-1; 3 2:3-4 0 5 2.1r —-5 1 r.L" ~ ~ ~ 2`,A /~ 2~~~~~~2 ~ ~ ~ ~ ~ 2 ~'Ax'-~c T -~~~~~~~ 120 \X ~\- i ~~~~~ <A ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ Q "~,E ~ ~ ~ ~ ~ ~ ~ = 80 Figur ~b aito atrsa 8 h o etadF eeec antenas on1978Versalles FM~ rfrene 8F1B12A ihpde cpctr. 8F 18B~~~l2~~AC without~c padercapcior ~~~~~~~~0

00 IA<K~~~~~~~~~~~~ 2 XI~~~~~~~~~~~~~~~~~~~ N!...,32 %~~~~~ i~~~~~~~~~) i'' 25 /Z< I' i~~~~~~~~~~~~~~~~~ i I~~~~iT 0180 Figure 43(c). Radiation patterns at 108 MHz for test and FM reference i N FMx, refer / B 2 w i p i 18B812-AC without padder capacitor. 109

4 —... -., —-- I ~ "l._-' -,.. -. -.;.~.....'*~ —-t~...'~~~~~-. 4'...:,..'' -..',~''-~i Z.i.'x ".,~'...:'.~.~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~8''-"... ~~-~u — >'-K., -V~ -a e>-.;~c..'..~jc x > 1..~.,.'..../'-~\il~ *..._:.......'-Zf'Z:-t'.'~ ~' ~ —' -- ~~~~~~~~~~~~~~~~ -~~~~~~~~~~~~~-KK>Y ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~~~I-' a) (b) 41-~~~~~~~~~~~~~~~~K; 1,K:.~ ~., —.:~, ~ ~ ~_r —+~,-.-~~~~~~~~......-4.''- ~ -.-. _.,,_ _ _ _ _ _ _.... -:~ K-:~ KU; - " ~ % -..,,,`~~~ ~?,- ma -... *I~``'~ ~ ~ ~ ~ ~ ~ ~~~~K ~\I K. —-— tr;~~~T~-c k.- 5r'1 4//,~~~~~~~~~~~~~~~ \~y~-' — 4'-I *j —j K~ F " i —~~. w-~ ~e~~~~~~~~~~~~~~~~~~~~.....:..: ~ _u ~ r....~-:.-;-.~: _ - for- tes atnaon17Vesils ()D8F-882A wih ade 41~~~~~~~~~1', —-:.":-1 — ~(.-.. -_:-: _... ~~~~~~~~~~~~~~~~~~~~~~~~~~~'~..._ —~ — ". ~' -''.~'..-'. — "'~ ~-:...-.-.-' -e''.'~~,..'~ ~~-.. i ~.,..-.. ~'''~ ~ \-.~,~>' r-~..' ~"""].-.-c=S, _caI'-_>:::-.. "-~ —. -'..'.:.~. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~' =1_~~. -.,...r..~.......... ".'" ".",:,: —. —-C-~'-', - ~.:",-, -'L,='.. d"~~~ —:~-''":~'~ i." ~/j'' -:~?-. ~"~':'.'<..:-~'~' ~'.-,"' i " n —~~~~~~~~-t —-,,....,J capac -i itor, b D84F-1B2-AC~ w 5ithu padr capa ci tor 110r

.,.... —-'.- ~ ~~.'- - ~ "/. t - t''.. __ * - _ 7t.t.l,'.' -- T.. _U* /......'." *-.""_ le- HI~lift MU AM 4- A- t r ast (a) (b)........-,-i -s.t' i-.' ~-~, - _-.'.' -, 9:..-.. —--.. -__:........~_'-<.r.-_(C) capaci tor, (b) D84.-1..81 2-AC wi.thout I a..ir capaci tor, (c c) FM reference. 12........ ~_~__ ~" ~.. ~-' ~' ~::.. I:-~;:~-~ —:77:1:.........z -, —:.....:- ~'- i - -~::-:'-~-' —~::-~ - -~ —---'~,:.'-' -'''~ — ~'-':J~-: -:-. ",......:... -...;- -'....? —-......... ~... —— ~-:-7_.. _ —~_: _ ___~.__~~ / ~:. - - -' _ —--—'-.. - - _, - ~.......z:.... ~ " —~..~~~~~~~~~~~~it UU -ou':.~~~~~~~~~~~~~~~~~~~~~-'tlq PUN.. — "a::-:.:;.:- ->:::: -Am-, -. ~.~'' MM A.-.-.:....S~.. -:.- -X —~-~,':.'..... — -.:: - ~:'::::::: —:-: —.'-l. _**~:...~. —..:,,.. ~-.:-...~..... -......_>:.,~?..,... ~::..:...- ~'.1.,... ".> —*~.:,::~ ~ ~.-.,.....'"~..*'"x"' ~'-~..'''' "'.'"' "'::-~ —:'" —-—'~-::.... 4b~~~~~~~~~~~~~~~~~~~~~..',.

the same performance, with a sensitivity larger than that of the standard antenna (Figure 43). 5.5 Performance Comparison In addition to the above results, the AM band field strength, the isolation characteristics at CB frequencies and the system C and Q at AM frequencies were measured for each antenna mounted on the test cars. The results of these measurements, and also the average sensitivities and VSWRs derived from the data in scetions 5.1 - 5.4, are shown in Table 9, and these can be used to judge the comparative performance of the test antennas mounted on the test vehicles. Based on the results shown in Table 9, the following observations are made concerning the performance of the SLC and improved isolation production series antennas: (i) Movement of the padder capacitor to the radio input increases the AM sensitivity of SLC antennas relative to the production antennas. The amount of increase depends on the test car. For example, the sensitivity of the SLC antenna relative to the production antenna is found to be 2 dB, 8 dB, 7 dB and 0 dB better, when mounted on Lincoln Mark V, Lincoln, Cougar and Versailles, respectively. (ii) The FM sensitivities of SLC antennas are larger than those of the production antennas. The padder capacitor improves the VSWR of the SLC antennas at 88 and 98 MHz, but degrades it slightly at 108 MHz. (iii) The CB sensitivities of the two test antennas mounted on Lincoln Mark V and Lincoln are almost identical. The SLC antenna on the Versailles has slightly better sensitivity, but the production antennas have more sensitivity (than the SLC) on the Cougar. The padder capacitor appears to reduce slightly the VSWR of antennas mounted on all test cars. (iv) At CB channels 1 and 19, the improved isolation antennas generally provide more signal isolation than the SLC antennas for all test vehicles. At channel 40 no such trend is observed. 112

t/1 q) i- -A - r-00 0CJ t~0 0 T O< 0* MO 0C =, "rt's * ~ o * * n " M f- CMc-De o CM o I -C; C\ CIOI - Lfl * * *C~ + 1+ O C..; U; C,,; c\., I- I! C' M C~i CD" a) CD- (., o.....- *-n O r *r *o r- C/> 1) i o g- m f~ o r 0:... r- CM o C)e o CI~?- n M c"j CM - -,i oc ~- C,~,~ C)~~~~ 00 J O 0 o 0Lsom 0ui^0 LOtOO Ce)C'O 00LL0 ^oLCLL (cNJJL (/< < 0 * * * * i......0 - C C I ~-0CJ ^ It)1O.... *Vf-S *- - >* *r- 1~ ~ ~ ~~~~+ 1 II I Lts'C% C~f-C\ J2~: - NZ 0 o ~- <^ Oulri OUmmt OwLCn OOOC% LoLL~o f-oocr ULor<_) ~ ~~ ~ ~~ ~ ~ ~ ~~~ ~ ~~~ ~~~~~~~~ a;) Ln 0...... C- r UlM ooo CLO ko JMCo r-f- i^'er >- &- <o ill i i i n CM co e^~- CM **~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~jco( z ~~~~~~~~~ I j-~~~~~~~~~~~~~C~ j rLI; * * * \ — - - - - - I CMC\M' C%,j C'-J S 2 2:1 uI} W LU ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~~~~ ~~~~~~~~~~~~~~~~~~~~~~~L Cm r-~~~~~~~~0L 0~ 0(' nU~0L uC 0 S ^ <o en *- o O^-^o Oao~- ch~=rc~~~~~~~~~~~~~~~~~~~~~~~~~~~~j Or-in ^OOLD r~~~to T o ) mroM V) J *- L.. * * 0tI r C^ -0 C 0 - 0 0L C - I/i 0 Io tooc\J r^.&flL(,..... r-<- - c\Jc\jcJ LIIIc\i <C Lu. U, 114+ ii, Pr~OOI- C1J4C<4 C - S2: LJ U, a) UL. 0 W h- S~~~~~~~S a) - __ ____^^___ _____-___ ------- _ ______ ______ — _________ _ _______, —---- t- ~ ~~~~~~~~~~~~~~~~~~~~~~~ %C C- 1S. M \ C C-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ LU c. r....... ji r- T O O OC s.. x LL~~.~ Ic- -^ 3 * C=CS Lno 0Q C)........ n r- i (r C. _o 0ii in I I iii nIII - ci i i ii i w rl C" co C, /= M ~c u - ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~~~I s-) C______________________ _ _ _ _ _ \ / ______ F — 0 C N N 0 ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ o L10UiD OCLCI o0r-yi Lmeo)aw c\j~LcI yop* rcooCr cLU C uC C O * *.. 00....C,oCMC C- 0 C-) 0 C I <QOlDCM J OLflL *~.... *- *- * SJ CMOUC\J 0TLL~y Z ~ ~ ~ ~ ~ ~ ~~c —' wJ- ~. *a —-- I I I CkO~D CM.,-.$.j 0 -0 ___ ____________________. _^_^_ ________. ______________________________-.... 0,'-, —''m_ —-, — --- - 2: — -.r- -,,,.- ----. _ — C-UJ~~~ ~ & Ju0 0. >~~~~~~~~~~~~~~~~~~~ > ^ IN } LDm oL n ^ ti r<.0 - m ooi.c ir LU >~L C)C u- I r >(- CM CD tnV U- C )L -S **S-0^ E u0 C~- r -- Z ~ ~~~~~~~~ ~ ~~~~~~~~ co- co c >*~ -~cri~ co )-w CIO co qr> 0 o uu-ton M: C- 0eu r:u'r"*r- OC ) o +J co M * * o- o - CC etl 4r. - ) V)- M _ _ -<, (3 -^ - - (3(> - V.-... i i ii l i0 iiii >S aa c os c V -< V U^^< 113~~~~~~~

VI. PANTHER PROGRAM The primary purpose of the Panther Program was to evaluate the performance of different antenna systems having variable input capacitances when mounted on a 1979 Ford LTD. For completeness some limited measurements were also carried out with a 1978 Lincoln Mark V. Both manual and power operated dual-band entertainment (ME and PE, respectively) and tri-band (MT and PT, respectively) antennas were tested, and the antennas and cars used are as listed in Table 1(c). Note that the three capacitance values (95, 123 and 202 pF) shown in Table l(c) under each test antenna are the nominal values of the input capacitances of the antenna obtained by chosing the proper cable length, or by adding extra in-line capacitance or by a combination of both. All the test antennas in this program were front mounted, in which case a 123 pF capacitance is normally used (202 pF when the same antenna is rear mounted). Generally, the test antennas were of the same nominal length. In the following sections each antenna will be represented by a symbol indentifying its type and input capacitance. For example, ME 123 denotes a manual entertainment antenna having 123 pF input capacitance. 6.1. Manual Entertainment (ME) Antennas on LTD The FM band horizontal plane radiation patterns of ME antennas with different input capacitances are shown in Figures 46(a)-(e). Observe that the ME 95 and ME 202 antennas have slightly less sensitivity than the ME 123 antenna at all of the test frequencies except 103 MHz where they have slightly more sensitivity. The shapes of the patterns are independent of the input capacitances. Results for the impedances of the three antennas are shown in Figures 47(a)-(c). 6.2. Power Entertainment (PE) Antennas on LTD Horizontal plane radiation patterns of the PE antennas at three selected frequencies in the FM band are shown in Figures 48(a)-(c). The results indicate that the PE 95 antenna has slightly more, and the PE 202 slightly 114

____. = 18~^ -5-== 1'1 — 0 20 25, ~30- 5 5 30 25' —— 20 1 - i 55 -- - -- ME95, --- ME 123, --- ME 202. 115 (MP) AntXen<A on ]979 ID. 7< ~ M95 M /2~... /E22

"-.00.- __- N I - i ".;. 150ZO'-:_ -. 25' - -- 30 —. —3Z: -35-25^-'- 20 15 0 5 ~2 7;I -. — ME95, -- ME 123, --- ME 202. 116 -6- Iy> -<,7I ~ KX ~~~~~ -~~~~~~~~~~NL - Fiue4() aitonpten t9 7 orMna netimn (MP)Antnnac, n 177ALT<

,= U 3 — 2- -- ME 95 0,, ME 202.'~-...:,'117,~

= 0~ Figure 46(d). Radiation patterns at 103 MHz for Manual Entertainment - -- -ME 95, - ME 123, - ME 2 02 -. Ix' 118.

I UI 0 =.' 80 Figure 46(e). Radiation pattern at 108 MHz for Manual Entertainment 119

- A -s k, -': —- t —' -;.4-.,UM..^^U —-'""" ^ "[ —'*'''J'r' ff ~""':" ^ ^.Ni.-^ r"'-..u,. ~;'.:.....:44_:_: - -:',,.. —. -..Y.:-__!:_- ",..'- ~," 12 = O. _,, j.. _?,-...... ~,-' - - - ( a)er t a n ( ). ( ) ~ 9. M E 1 3 ( ) M E:.'.:..-..''L;......~_-:.:-..........1.20

/__= O~ I 60 Figure 48(a). Radiation patterns at 88 MHz for Power Entertainment (PE) antennas on 1979 LTD. -- - PE 95, -- PE 123, - PE 202. 121 -~"~~~~~~~~~~~.: ~.:~~~~~~~~~~~~~~~~~~-L

— =.-== —10 —{=-=~}-!15i|-== —— 20..... 25' ~ 30....35'- =~-4- ~ = —-— = 30 - O 25 - i, ~,20 - J -15, 15 ~ —105Figure 48(b). Radiation Qatterns at 98 MHz for Power Entertainment (PE) antennas on 1979 LTD. -. —-. PE 95, PE 123,.-.. PE 202. 122 OF) Antpnnac, nn lq~~~~~q LTD~

-- -- PE 95,1, -- PE, —[ 202, 123 3. -F rP 95,c PEdiatio 123, - PEs at 202rt. - 123

less, sensitivity than the PE 123 antenna at the three test frequencies. Again, the shapes of the patterns are found to be fairly independent of the input capacitance. Figures 49(a)-(c) show the corresponding impedance results. 6.3. Manual Tri-band (MT) Antennas on LTD Horizontal plane radiation patterns of the MT antennas at three selected frequencies in the FM band are shown in Figures 50(a)-(c). At all three frequencies the MT 202 antenna is considerably less sensitive than the MT 123 antenna, and the PT 95 antenna about 1 dB less sensitive than the MT 123. The corresponding patterns for the three antennas at the CB frequencies are shown in Figures 51(a)-(c) The patterns and sensitivities are almost identical at all frequencies with the exception of the MT 202 antenna which has slightly less sensitivity at the lowest CB channel frequency. The impedance results at FM and CB frequencies for the MT antennas are shown in Figures 52(a)-(c) and 53(a)-(c), respectively. 6.4. Power Tri-band (PT) Antennas on LTD The radiation patterns of PT antennas measured at FM and CB frequencies are shown in Figures 54(a)-(c) and 55(a)-(c), respectively. Figures 54(a) and (b) indicate that at 88 and 98 MHz, the PT 123 antenna has significantly less sensitivity than the PT 95 and PT 202 antennas. Of the three antennas, the PT 95 has the largest sensitivity at the three test frequencies in the FM band. As can be seen from Figure 55, there is very little difference between the patterns of the three antennas at CB frequencies. Figures 56(a)-(c) and 57(a)-(c) show the impedances of the three antennas at FM and CB frequencies, respectively. 6.5. Performance Comparison for Antennas on LTD In addition to the above results, the AM band field strengths, the isolation charactercitics of CB frequencies, and the system C and Q at 124

*7-w- I.,.m(.*. * - *''.-',.";. -. A. 7 *"'*->''*,,*-**:'.^ *',' ~,;'.'-,'..."._.'-"4 —' —';- -'".'I-.'i' /.'.-, * ***'L'*'' " =s,' ", s - ^ -*,. = -. ~* ^'*^'^^m^ ^ - "' S -^- t -, — 7." --- -.'"i". —' "-,. —'. ~ ~'.,.,. -.^:<.- i^^^:.:$^^...........~,,-~ —.~.;~.,.~:.'.. -. —.-,3.,-. ta~~inmen~t an~tennas~ on ~'979 L..D. / ~~~~> —--— ~~~~~~~~~I

= 180~ Figure 50(a). Radiation patterns at 88 MHz for Manual Tri-band (MT) antennas on 1979 LTD. *..* MT 95, MT 123, MT 202. 126

_ = 00 Figure 50(b). Radiation patterns at 98 MHz for Manual Tri-band (MT) antennas on 1979 LTD. *.-* MT 95, - MT 123, -- MT 202. 127 46-~~~~~~~~~~~~~~~~~~~~~~~~

~~~~~~~~~~~~~~~,1 L. r~.':',' -' ~~~~~~~~~~~~~~~~"'..''i I' "'J'- ~..'.', *:. /':.^ ^'<'' *'. _,. ^ r T''...l^''" "''' *. ^' t -y -'*'.-., *'.' i..-..~ —,.'.._, L ~..,-..~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ *'_;s /^ ~!'N-.~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~.-.'i.......,: f~ - —: _.____;.' *,, —"<' —-'......._:.-'..............:.';:-.:"..7'*.-... ~~~~~~~~~~~~~~f:.::.-:;.'.^.. ^ -. ^S-. ** ".... *: ~~.....-:: —_ )r c~~~~~~~~~~~~~~~~~~~~~~~~:-:..: —— t"~.-' —'"' -"J-" -:'' ~. /';;: ~^'^....' "".:1' L-.-..- -,.:_:..:!. \ -~.. —.'~-.-.-.^".::,-i ---.. -'^. * *...* r ~ 1 /,, ~-,:.,,:.:'..... Ir~ ~~ Fi.ure 50(c). Radiation patterns at 108 MHZ for Manual Tri-band (MT) ~nn,m n~z n I - ITD -......' 9 -20 ~~ ~ 2...,.-IJ~-~...... c'' -Ce -... C~~ ~~~~., ~, ~:'-,~,.:...? -... i -l_- _ ~' 4 ~J_~c.......-,~..- —. — ~ —-- - -- _..-' -'I ii -' _ ~'.c... T9,.... M T - 1 23.... MT22 128

= 00 w.15 /~~~~~~~~~,, K' ~l~cr~ T~i-T~-~-L' 25' 30 A ~~~~~~~~~~~~~~~~~~~~~~~~~ F0 —-- 515-~ —-~2 ——' —-2 303' —~ 5 3 ~~~5 2 5 1 \~~~~~~~~ A jI& t < \ 4'~~~~~~~~~~~~~~~~~ I~I'~ xx Figure 51(a). Radiation patterns at CB Channel 1 for Manual Tr-band (MT) and reference antennas on 1979 LTD. GB Reference,....MT 95, MT 123, aAAAA MT 202. 129

00 rI' /y\ I! fi 20 1$ =180~ Figure 51(b). Radiation patterns at CB Channel 19 for Manual Tri-band IA- 1 Tr' 130 \Y\VC~~~~~1~~ ~ ~ (-h- -/\ - * 1s-2a —-— ~~~~-#25 30 ~ L - 0 1 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~3 /~~L!vrlCs, \ \ III ~~~~~~u A - i~ X X XY ~ ~i~~` ~~~~U Y\A ~\ Y\\~r: \ LCT \ I rL~ icC-~-ft-ci ~ iI i PK:uI 25 i b ipll~~~~~~~~~~~~2 -K -. 130

rAP r73jf_.__ _ _........ T:^-^' *:/<~'* *^<^^^-^:^ ]/_ **.<<**. **>^... **v. - ---- CB" RM --.... ---—'''-~''-'~':::' —''''~/~"''''',~-:"'~:"'.-"''':' -"..:-'..... = —'":~..: ~- -: ~ ql.-',.-..z-',;,.:-,'-/ —.'' —-----'.v',,-''..'': ~,.~'! ~,......, —.......,~-,,.,..,...~.. Fiau~~~re 1c.Rdainpten tCBCanl4 o aulTibn (MT) an referece antenas on 979 LTD CB R efeec,...M95...MT13 aaMT2. 131

-- ~ "'lt --- -- -. ~ —--—: —-- --..j..Al - I;. -. -...,- -- "'' -' -?: - --:~::~ i -,:,," (a ( (b) - ---- _ —--- ---- - _. _ ""-''-, "''.. —' L,-'~::-<>':- "''"-'/ —.''' —.- ~.':::~:::....:' ""'..,t rb ~ ~~ J "t L-ZlL

' -.... -4~.- ~-':.-~?-'L~ —: —-__ _ a._. ___.....-"'"____ -a' ~ "'r-~~~~~~~~~~~~~~~a ~~~~~~~~~~~~~,:2__~-7.- t.. r -Vc $4 ~~ s~' / - 4.~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~ ~~. T~,~~~~~4. -'~';., ~ ~ ~ 4 ~ -.'~''.-"'.-:.':'-_.-.'.'; -.j,. ~.,...:/-'-."' —'';:::t 0~ — 7~' ~ ~. " ",'",""'": —— fX —-,.',''/.'w,,,,. ~, -'VK'.....,.- ". 4.' - 7'-...."'.:... —- -- — __-(.....: _: __._, -' —---— 4........... u_ —--- T'':: / 1 h~`"-, 3', ~- -_~,,........ -~~~~~~~~~~~~~4'.~ -_.. -.~~,' -~_.-. —::__,-....:..~-..~. 2,~~~~~~~~~~~~~~~. ~.. ~.. _-C._ _.._~_ C ~__^.....:~-~-~ ~cr~~~~~~~~~~~~~~~~~~~~~~~~' —-cc',,_-' — -.''.-.... v.' "'""' —: ": -.' "'d.:"-'-' ~.::...'~,?: ", —-',,"'.~ —-'::{-::'..~:j'':> —,? —,""~ ( ~) —-~ —--- ~~- Figre53 Impeda(nce chractritc at C B - frqecefrMna (a T9, (b T 2,(cMT2. _-_ i — r i ~ —-...133

- - - PT 95, PT 1_23, PT 202. 134 1 5 = 1800 Figure 54(a). Radiation patterns at 88 MHz for Power Tri-band (PT) antennas on 1979 LTD. 134

Li = 180~ Fiqure 54(b). Radiation patterns at 98 MHz for Power Tri-band (PT) antennas on 1979 LTD. -. - PT 95, PT 123, -.. PT 202. 135 uJ 20 AK

I 20<. 31 25 20 15 i25 = 180~ Figure 54(c). Radiation patterns at 108 MHz for Power Tri-band (PT) antennas on 1979 LTD. -.... PT 95, --- PT 123, ----- PT 202. 136

_ = 180 Figure 55(a). Radiation patterns at CB Channel 1 for Power Tri-band (PT) and reference antennas on 1979 LTD. CB Reference, - - - PT 95, -- - - PT 123, - - - - - PT 202. 137 Xy"r

/'I;.. I k-1 2 — ~3~_ 3__ i~: ~ 25 1 —-. oL —-25 138 3. = 180~ / A( 1 38

25 = 180~ Figure 55(c). Radiation patterns at CB Channel 40 for Power Tri-band (PT) and reference antennas on 1979 LTD. CB Reference, --- PT 95, — -- PT 123, ----- PT 202. 139 A:~~~~~~~~~~~~~~~~-c / 7 ~ ~~~~ - ~

"ZI A- a ^^^^^^^^^^^^*^^ ~. - i-! —i i " *....- U M ^-. —'...,.. --- -----— _'.-','.....-iI —~.-:-:~_%'? ~ ~ / f -''':"' —-~""-'''~'',',.''-." (a) (b) -.'/.'.'.:-. -:: -.' --. -.' 140.""',' (c) Figure 56 Impedance characteristics in the FM band for Power Tn band~~~~~~~~~~~~~~~~~~~~~~~~~~ (P)atna~o 99LD (a) PT 95, (b)-.- PT 123 (c PT-~ 20...~*. 140~~~~~''','',-'-"/~-t-U"~-,,~~x-.~'.,

~~.',~:,~...fe....;'-,' ~.,,~~ Z-~_~~~,SII%<.-'~.~,'/.,. x~ 4., -. -. -~: i-t,-,, %:..:.j.. j j-...-...,'<* *,.... r, -—._..'.... v-'v'7-__-!'v^.'. A.. E (a) (b) q-'-' -'.' -"'J.': &nu- -,.':';'/"..*.' Figure 57. Impedance characteristics at frequencies for Power' (a) PT 95, (b) PT 123, (c) 202. (c)..~-~L~ >'-'>..'-~.~..~~ L.~'..-'%~_::'"~ ~"-.'............... Figure 57.".'m.edance characteristics at.'*.._." C'."' frequencies for Powe Tn-band.,'.' ~.'.."...':',.~' (P-.._.T) antennas....' on 1979 LTD.>.'~'. /~%...;','....-,'...' —?~'~..,-,.v"~'.,..,,.'. "'. (a) ~-.~':~..~:.:~~;.. PT 95,~...,..~...''...::z, (b)-~_ PT 123, ~~,(c) 20..,, 141~........ —:-:~,-~-.:.:~,..).,.

AM frequencies were measured for each antenna mounted on a 1979 Ford LTD. The results of these measurements, and also the average sensitivities and VSWR's derived from the data in sections 5.1 - 5.4, are shown in Table 9, and these can be, used to estimate the effects of the input capacitance on the performance of a test antenna mounted on the LTD. Based on the results shown in Table 10, the following observations are made concerning the effects of the antenna input capacitance: (i) The AM sensitivity of ME and PE antennas is substantially independent of the antenna input capacitance. The MT 202 antenna has appreciably more, and the MT 95 less, sensitivity than the MT 123 antenna. The behavior of the PT antennas is similar. (ii) The shapes of the FM band patterns are independent of the antenna input capacitance. The average sensitivity of ME 95 and ME 202 antennas is generally less than that of the ME 123, the maximum reduction of sensitivity being about 2 dB. Over the FM band, the PE 95 antenna can have about 1.5 dB and the PE 202 about 2 dB sensitivity relative to the PE 123 antenna. The MT 95 has about 1 dB less sensitivity, and the MT 202 antenna is as much as 8 dB less sensitive than the MT 123. Both the PT 95 and the PT 202 antennas have substantially larger sensitivities than the PT 123 antenna. (iii) There is no general trend in the behavior of the VSWR at the FM band frequencies as the input capacitance is varied. (iv) The CB sensitivities of all the antennas are generally within 1 dB of each other. The input capacitance seems to have some effect on the VSWR at CB frequencies but no general trend can be cited. (v) The PT 202 antenna has the poorest CB isolation characteristics, to the extent that these may not be acceptable. With the other antennas, the input capacitance seems to have some effect on the isolation characteristics which otherwise stay within acceptable limits. 6.6 Results for Antennas on 1978 Mark V Due to unavailability of a 1979 Ford, results were collected with a 1978 model car. This section describes the results obtained with manual an tri-band antennas (MT and PT, respectively) front mounted on a 1978 model Mark V. 142

TABLE 10. PERFORMANCE DATA FOR TEST ANTENNAS ON 1979 LTD. ANTENNA TYPE PARAMETER ME PE MT PT 95 123 202 95 123 202 95 123 202 95 123 J 202 AM Sensitivity (dB/m) 0.76 MHz -68 -68 -68 -68 -67 -68 -70 -70 -69 -66 -67 -61 1.10 MHz -76 -76 -76 -78 -78 -77 -80 -75 -77 -75 -76 -77 1.60 MHz -84 -84 -84 -84 -84 -84 -92 -90 -85 -382 -82 -80 Relative FM Sensitivity (dB). 88 MHz -1.51 0 -1.51 1.51 0 -2.18 -1.13 0 -7.72 12.61 0 1 3.12 98 MHz 62 0 - 2. 18 0 -2 36 12 11 0 4.27 108 MHz -1.40 0 -1.40 1.23 0 |-.16 -.97 0 -3.30 4.04 0.29 Relative CB. Sensitivity (dB) CH 1 -7.03 -7.78 -9.85 -.62 -.76 -.76 CH 19 -6.62 -7.17 -8.20.44.30.62 CH 40 -6.61 -6.24 -6.24 -6.24 -.75 -.10 FM VSWR 88 MHz 2.45 2.54 2.20 4.53 4.20 2.17 8.33 7.89 15.00 20.00 17.50 13.00 98 MHz 2.13 2.22 1.37 2.09 2.06 8.09 4.11 3.78 4.50 9.22 9.00 2.83 108 MHz 4.48 4.53 6.11 3.95 3.88 5.00 4.16 3.48 6.08 2.70 2.30 1.33 CB VSWR ____.l CH 1 ^^*^r ^^^^ 2.33 3.00 4.71 3.10 3.32 3.32 CH 19 1.35 1.96 2.64 1.41 1.48 1.56 CH 40 2.08 1.93 1.29 1.86 1.73 1.65 Isolation (mv) CH 1 200 125 165 218 I 300 850 CH 19 125 180 122 120 I 170 775 CH 40 _____ _ _ _____, 140 360 200 143 j 170 520 AM Capacitance (pF) 0.6 MHz 95.5 123.89 202.0 98.0 128.0 200.0 99.0 125.0 210.0 97.0 125.0 202.0 1.0 MHz 96.25 124.95 202.0 98.0 129.0 202.0 99.0 127.0 212.0 102.0 127.0 203.0 1.5 MHz 98.3 125.0 201.0 101.0 332.0 203.0 112.0 130.0 215.0 100.0 130.0 202.0 AM Q 0.5 MHz 1776 3382 2357 1873 3917 1422 1334 741 511 1138 1032 1403 1.0 MHz 1648 2543 3113 1550 3138 1074 1814 1082 404 923 676 1010 1.5 MHz 1163 1917 893 1338 2544 822 2251 1141 243 576 487 651 143

The horizontal plane patterns at FM and CB frequencies obtained with various MT antennas are shown in Figures 58(a)-(c) and 59(a)-(c), respectively. Note that all the test antennas have similar patterns, and the impedances are shown in Figures 60 and 61. The corresponding results for the three power tri-band (PT) antennas are shown in Figures 62-65. In addition to the above, the AM band field strengths, the isolation characteristics at CB frequencies, and the system C and Q at the AM frequencies, were also measured for each antenna. The results of these measurements, and also the average sensitivities and VSWR's derived from the data in Figures 58-65, are shown in Table 11. The general behavior of the MT and PT antennas on the Lincoln Mark V is similar to that found for the corresponding antennas mounted on the 1979 Ford LTD (see section 5.5), and hence is not discussed further. 6.7. Discussion There is no unique input capacitance value for the manual and tri-band antennas which would provide better performance according to all the performance criteria. Although the 202 pF capacitance system seems to provide a better AM sensitivity, the PT 202 antenna has the worst isolation characteristics, and on the average, a 123 pF input capacitance would provide the best overall performance. 144

= 180~ Figure 58(a). Radiation patterns at 88 MHz for Manual Tri-band (MT) antennas on 1978 Mark V. MT 95, - - - - MT 123, - - - MT 202. 145

Jr 5 = 180~ Figure 58(b). Radiation patterns at 98 MHz for Manual Tri-band (MT) antennas on 1978 Mark V. MT 95, - - -- MT 123, - - -MT 202. 146

I= 180~ Figure 58(c). Radiation patterns at 108 MHz for Manual Tri-band (MT) antennas on 1978 Mark V. MT 95, - MT 123, - - - MT 202. 147

148 20 I/I -__ = 1800 Figure 59(a). Radiation patterns at CB Channel 1 for Manual Tri-band (MT) and reference antennas on 1978 Mark V. 148

= 180~ Figure 59(b). Radiation patterns at CB Channel 19 for Manual Tri-band (MT) and reference antennas on 1978 Mark V..- - CB Reference, -- MT 95, ----- MT 123, ---- MT 202. 149

30 I - 0~2 3 ___ = 180~ Fioure 59(c). Radiation patterns at CB Channel 40 for Manual Tri-band (MT) and reference antennas on 1978 Mark V. - - - - CB Reference, MT 95, ----- MT 123, - - - MT 202. 150

(a) (b).:.4..n ( MT. at n on_ _ 1,.. V - ~ 15''...., *-, im,.slu! -g ",^,; K4. -i, —:- -4(c ). ~ ~ ~ ~ ~ ~ ~ ~, (a( (b) 9 ( M.23, ( (c) Figure 60 Impedance characteristics in the FM band for Manual~~~~~~~....... TibnsM)atnaso 98~akV (a) MT 95, (b) MT 123, (c) MT 202.~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~A

~''> 0 "- - __.'.,~. —.-.,:<Sj<::,,M-. le'ttt |,' th t tt _t <!'., "'., -tbl tt t r. -.; t.* m*'l:':-; —: -.. -.G;-r'- m'l.' " m- Figure 61. Impedance characteristics at C6 frequencies for Manual (a ) MT 95, (b) MT 123, (c) MT 202.(b) 152.*', ~ ~'.'.~-'.'- " —-— _.->-~-~-,,' ~ ~'~' ——. —---—' —"-' —--- C1 >:-",L-' I "' -L~~~~. _.~~ ~ 5-:'~' ~.-/~ —'x —-"?~-", ~ ~-~_' ~::~ L:~:; —~:~-: ~:'~:-~'.- ~ -: —y,'(c)~ ~~~~~~-!~... ~...... Figure~~~~~~~~~~~~ — 61....... Impeanc characteistics.a GB, freuenie fo-ana Tn-band (MT)........ " antenna on 197 Mar V...... (a).T.9,.().M 123 (c). MT 20.........;._______~ 152~.

= 180~ Figure 62(a). Radiation patterns at 88 MHz for Power Tri-band (PT) antennas on 1978 Mark V. - PT 95,.. PT 123, - - -PT 202. 153

0 = 180~ Figure 62(b). Radiation patterns at 98 MHz for Power Tri-band (PT) antennas on 1978 Mark V. PT 95, PT 123, - - 3- PT 202. 154

155 -__ = 1800 Figure 62(c). Radiation patterns at 108 MHz for Power Tri-band (PT) antennas on 1978 Mark V. 155

= 180~ Figure 63(a). Radiation patterns at CB Channel 1 for Power Tri-band (PT) and reference antennas on 1978 Mark V. - - - CB Reference, - PT 95, PT 123, - — PT 202. 156 15ur 20a) 25ito pten 30 35 hanne 30 5for~-2 Poe10ibn (PT) ad refrenceantenas on1978 ark35

= 180~ Figure 63(b). Radiation patterns at CB Channel 19 for Power Tri-band (PT) and reference antennas on 1978 Mark V. - - - - CB Reference, - PT 95, ----- PT 123, - - - PT 202. 157

Figure 63(c). Radiation patterns at CB Channel 40 for Power Tri-band (PT) and reference antennas on 1978 Mark V. - -... CB Reference, - PT 95,.. PT 123, -.-.- PT 202. 158

^^^i.lll^ — *l A —-i', -~er tnutz.t ^^^liAi^Q^3'1'^"' -:-'.,;,^ ut-4; -:1 l-xo. s! 3-.- -3.-,..:....~:.....: -:_-:.-..........-.. Figure 64. Impedance characteristics in the FM band for Power Tri-band (a) PT 95, (b) PT 123, (c) PT 202.... 15. 4- 3 (T- -(teA-l I1 Ma- V-... Figur 64 mpednce haracerisics n th FM bnd fr Poer T oan (PT)antenas n 198 Mrk V._~ (a) PT 95, (b) PT 123, (c) PT 202.~~~~~~ 159~~~~~~~ —--— u —--

- -~~1 _ ti- ^^^ri^~^?^'^ -*'*>-. -.. - -— M-' m;* — ""-*'*'"~*'' *< —- — v —^ * - "^ ~^ ~'''.:,...:.~.....'. - -~ - 7- -. ~...T * +.-. -- 7 -,. (a) (b) dfn o...-| — ^..... ___ - 9, _|.___i_ — _-_-__ ___ _ - - ^.;....a. —.- -......' ~.,..-...~.. -~:~__~-, *~'-.j.'"~^''. -^, (c) FiQure 65. Impedance characteristics at CB frequencies for Power Tri-band (PT) antennas on 1978 Mark V. (a) PT 95, (b) PT 123, (c) PT 202. 160

TABLE 11. PERFORM4ANCE DATA FOR TEST ANTENNAS ON 1978 LINCOLN MARK V PERFORMANCE COMPARISON PARAMETER ANTENNA TYPE MT PT, 95 123 202 95 123 202 AM Sensitivity (dB/m) 0.76 MHz -66 -64 -59 -63 -65 -62 1.10 MHz -76 -71 -68 -71 -73 -70 1.60 MHz -84 -81 -76 -81 -82 -78 Relative FM Sensitivity (dB) 88 MHz -1.1 0 -4.0 +1.0 0 0 98 MHz -1.2 0 0 +0.7 0 +4.5 108 MHz -1.0 0 0 +0.8 0 -1.2 Relative CB Sensitivity (dB) CH 1 -0.5 0 -0.8 +1.2 0 -0.9 CH 19 -0.9 0 -2.0 +0.2 0 -2.0 CH 40 -1.1 0 -0.2 +0.5 0 -0.5 FM VSWR 88 MHz 8.89 7.89 15.6 15.0 17.92 12.33 98 MHz 3.87 3.25 4.9 10.6 10.74 4.59 108 MHz 3.89 3.0 5.22 1.72 1.51 1.68 CB VSWR CH 1 2.43 2.52 2.50 2.53 2.40 2.42 CH 19 1.31 1.11 1.15 1.22 1.34 1.32 CH 40 2.19 2.47 2.29 2.33 2.44 2.42 Isolation (mv) CH 1 245 215 720 175 190 208 CH 19 128 109 460 100 230 238 CH 40 160 195 360 170 400 228 AM Capacitance 0.5 MHz 98.7 125.2 209.8 98.7 125.2 209.8 1.0 MHz 99.4 127.0 212.1 99.4 127.0 212.1 1.5 MHz 11 112.5 130.0 2 15.5 112.5 130.0 215.5 AM 0 0 5 MHz 1334 741 511 1162 1032 1457 1.0 MHz 1814 1082 404 902 680 1052 1.5 MHz 2251 1141 243 640 485 694 161

VII. STUDY OF SPLITTER BOX This chapter presents the results of a study to evaluate the impedance characteristics of the AM/FM and CB ports (ports 1 and 2 respectively in Figure 4 ) of the splitter boxes associated with the tri-band antennas. The measurements were carried out without cars and following the procedure outlined in section 2.5. One manual entertainment (ME) antenna of length 32 1/4" and two base-loaded tri-band antennas (MT and Motorola), each of length 40", and mounted on a 4 foot - square ground plane were used as test antennas. The loading coil of each tri-band antenna had a tuning slug which could be adjusted for a desirable VSWR at the CB frequencies. During the measurement the tuning post was placed at the top, middle and bottom positions, and at each position the effects on the VSWR at the CB and FM ports were studied. Impedance properties of four splitter boxes, referred to as Box 1 (square type), Box 3 and 6 (round type: they are similar) and Motorola Box, were used. As shown in Figure 5, each splitter box circuit consists of two distinct branches. One (the AM/FM branch) consists of a parallel tuned circuit, tuned to the CB frequency, whose purpose is to isolate the CB signal from the AM/FM radio. The second branch, called the CB branch, consists of a series L-C circuit tuned to a frequency in the CB band, and guides the signal from the antenna to the CB port and vice versa. The tuning frequencies of these two circuits can be adjusted with the help of two tuning slugs, referred to as the FM and CB slugs, respectively. 7.1. Results Figure 66 shows the CB and FM band impedances of the MT antenna as a function of the position of the tuning slug in the loading coil. Observe that the position of the tuning slug does not appreciably change the FM impedance, but has considerable effect on the CB impedance of the antenna. Figure 67 shows the FM and CB band impedances at the appropriate ports (1 and 2, respectively) of splitter box 6, obtained with the antenna port (port 3) terminated with 100 Q load. While obtaining the FM and CB 162

ENGR. OPERATOR ______ DATE FILE No.!.^'^\\ { 49 Figure 66. Effects of the antenna tuning slug positions on the test antenna impedances at FM and CB frequencies. o slug at top, * Slug at middle, x slug at bottom. 163 45 40~~~ —'4'I0

ENGR. _____ OPERATOR _____DATE __ FILE No..A.ELENG6IH TIWAR LOAO..q, I/ ~ ~ ~ ~ ~ ~~.,A i 164-~ ~ ~. jlsa11.50~~~~~~~~~~~~~~~-N', E' fA SE "~.,L'^ —--- POSITIVE ASE ANIE -504 Figure 67. Effects of FM tuning slug position on the CB and FM band impedance of the test antenna connected to the splitter box 6 with CB slug in all the way., slug at top, 0 slug at middle, x slug at bottom. 164

results, the CB and FM ports were terminated by 50 Q and 100 Q loads, respectively. The results shown in Figure 67 were measured with the CB tuning slug in all the way and with three positions of the FM tuning (or isolation) slug. The data indicate that the adjustment of the FM tuning slug has no effect on the impedances at the FM and CB ports of the splitter box. Figure 68 shows the effects of the CB tuning slug position of the impedance on CB channel 19 at port 2 of the splitter box 3 with ports 1 and 3 terminated by 100 Q and 50 a, respectively. Note that the positions of the CB tuning slug are represented by 1, 2... 8 in Figure 68 with 1 signifying that the slug is all the way in and 8 signifying that the slug is completely out. From these results it is possible to obtain the effective impedance of the series L-C circuit of the CB branch of the splitter box. Figures 69(a)-(b) show the FM band and CB impedances of the MT antenna connected to the splitter box 1. The corresponding impedances of the antenna without the splitter box are also shown in Figure 60 for comparison. The corresponding results obtained with the MT antenna connected to splitter box 3 are shown in Figures 70(a) and (b), and for the Motorola antenna and its associated splitter box in Figures 71 (a) and (b). The results indicate that the splitter box generally transforms the CB port impedance towards matching, whereas the transformed impedances at the FM ports generally stay away from the matching condition. Figure 72 shows the FM band impedance of the ME antenna which does not need a splitter box. The results are presented here to indicate that this antenna is far from matched at the FM frequency and hence would produce large VSWR. 7.2. Discussion Based on the above results the following comments are made concerning the performance of the splitter box: (i) The adjustment of the FM tuning slug does not affect the impedances at the FM and CB posts of the splitter box, and merely isolates the CB 165

ENGR. OPERATOR DATE FILE No.___. tAIELENGTH ~ N1AON LOAD. 0lg- NEGATIVE PHASE ANGLE e i;T, POSITIVE PHASE ANGLE -5Bl_ Figure 68. Effect of the CB tuning slug position on the impedance at Channel 19 for the test antenna connected to splitter box 3. 1 - slu in all the way, 8 - slug out all the way. 166~~~~~~~,/

ENGR.__ OPERATOR __ _ DATE FILE No. ^IAVELLNCTH 3WA0RD LOAD-. _ /i:<~~~~~~/ /' N —'"'- -:'-/".... 167 45r __ +. __ _ ~ - 4 0000'antenna only, xxxx antenna + splitter box 167

ENGR. _____OPERATOR DATE FILE No. v^iVENCTGTH OWARD LOAD ^ ^ -.<n O o-^ ^49 and test antenna for FM band. aooo antenna only, xxxx antenna + splitter box 168 X~~~~~ 29~ ~ ~~ ~ ~~~~~~~~30~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ___.5... \ 440

ENGR. _____OPERATOR _____DATE __ FILE No._' lAVL.#T# rOWAD LOAOWR D 49.. 4'^^ v ^ J C — 0,,' 0000 antenna only, xxxx antenna + splitter box ooooantnnaon,,,,'anena. spite o.~.69,..

ENGR. OPERATOR _____ DATE __ FILE No._,. AEiNGTN T OWARD LA..__ ooo0 antenna only, xxxx antenna + splitter box 17047 // i 4r I,1106 - 40.-5.,._.-, A.'E50- GATIVE PHASE ANGLE [SITIVE PHASE ANGLE! it~~~~~~~~~~~~~~~~~~~~'I~'-T-''-?,:~L i,

ENGR. OPERATOR DATE FILE No. A.. L.CET, TOWARD LtAVT - 1 0.49../?dAD,,~. Il50- NEGATIVE PHASE ANGLE --, "-,'.C!' -- --—,- -POSITIVE PHASE ANGLE — W,"_ ~_1,(,'9 0000 antenna only, xxxx antenna + splitter box 171 b"ox.;~.-.-'tnf"b —nd. I - - - - - - - - - -- -L- - -- -- -. - -'I! L..& - L -,

ENGR. _____ OPERATOR_ DATE __ FILE No._,IIAELENGTN TOWARO LOl. -_.1'0 0.49, i — 4- "7' J'''" 1^ 40 ^^ ^1=^^3 =* ^ S 50- NEGATIVE PHASE ANGLE P I POSITIVE PHASE ANGLE — 50 Figure 71(b). Impedance characteristics obtained with motorola splitter box and test antenna for CB band. ooooantenna only, xxxx antenna + splitter box 172

ENGR. OPERATOR DATE FILE No..,__ _ _._ ttllEuGTN TOWARDl LOAD._.1 0 ~ 49 Figure 72. Impedance characteristics of the Manual Entertainment antenna ME 202 at FM frequencies, no splitter box used. 173 "X.x,<-'~~~~~~~~~~~~~~~~~~~~5

signals from the FM port. (ii) The adjustment of the CB slug affects the impedance, and hence the CB VSWR, at the CB post only. As a result, with proper adjustment of the CB slug the VSWR at the CB post generally stays within acceptable limits, but the VSWR at the FM post can be fairly large. (iii) The series L-C circuit at the CB branch is not necessarily required to be tuned exactly to the CB frequency at which a low VSWR is desired. Its function is, in fact, to provide the appropriate amount of reactance so that the combined impedance of the antenna system yields the desired VSWR. 7.3. Recommendation At the present time the splitter box provides acceptable VSWR at the CB frequencies. There being no provision for impedance adjustment in the FM band, large VSWRs usually exist at the FM ports with consequent loss of FM sensitivity. Our study indicates that it may be possible to improve the FM sensitivity of tri-band antennas by introducing an extra variable reactance in series with the FM branch of the solitter box circuit without affecting the antenna performance at CB frequencies. It is recommended that a further study be initiated along this line. 174

VIII. ACKNOWLEDGEMENT We are pleased to acknowledge the benefit of several discussions with Mr. Susheel Bery and Mr. Al Partington of the Ford Motor Company. We also wish to acknowledge with thanks the help of Mr. WF. Parsons, Mr. T. Repucci and Mr. D. Brill during the measurements. Suggestions and counsel from Prof. T.B.A. Senior, Director of The Radiation Laboratory, are gratefully acknowledged. The authors wish to express their sincere gratitude to Ms. Sandra Bowne for her expert and patient typing of the manuscript. 175

IX. REFERENCES [1] D.L. Sengupta and J.E. Ferris, "A Study of CB, FM and AM Antennas for Automobiles," The Radiation Laboratory Technical Report No. 320626-1-T, Ann Arbor, Michigan 48109, September 1976. 176

X. APPENDIX A MOTOROLA ANTENNA PERFORMANCE The present Appendix gives results obtained with the Motorola tri-band antenna front mounted on a 1978 Cougar. Figs. A. 1. (a) - (c) show the horizontal plane radiation patterns at selected CS frequencies obtained with the test and X/4 CB-reference antennas. The corresponding FM band patterns obtained with the test and the standard FM antennas are shown in Figs. A. 2 (a) - (e). The impedance characteristics of the test antenna at CB and FM band frequencies are shown in Fig. A. 3. The performance comparison chart for the Motorola antenna is shown in Table A. 1. 177

reference antennas on 1978 Cougar. --- Motorola, ---— _ x/4 CB reference 178 215 35 Figure Al (a) Radiation patterns at CB channel 1 for Motorola and reference antennas on 1978 Cougar. 178

at~~~~; t I -. __ = 180~ Figure A1 (b) Radiation patternsat CB channel 19 for Motorola and reference antennas on 1978 Cougar. 5 0Motorola, -.2.........- A/4 CB reference 179

II __ = 00 2 Figure Al (c) Radiation patternsat CB channel 40 for Motorola and reference antennas on 1978 Cougar. ------ Motorol a, —. —-- A/4 CB reference 130 Figure Al (c) Radiation patterns at GB channel 40 for Motorola and~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~"' reference antennas on 1978 Cougar.~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~, Motorola,-X/4 GB reference~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~:'' 180~~~~~~~~~~~~~~~~-t

LI reference antennas on 1978 Cougar 30 T _ Motorola, ---— FM Reference 181

/ 182

I = 180~ Figure A2 (c) Radiation patterns at 98 MHz for Motorola and FM reference antennas on 1978 Cougar 1-83

-T'~~~~~~~/' I, 20 i l! II' 35 t //'18 35 7'I I~~ ~~~~~~~~~~~~~~I 30 K 25r 2~~~~~~~~~~~ _____~u 1800 Fiur A2()Rdainpten t 0 / o oooaadF reference antennas on 1978 Cougar~~~~~~~~~ 18

00 7/ / 20 25,% K 5 1 5 2 25 1 30'-~425- -20 15 1 5 3 - 1+ I -15 Fiue 2(e aiain aten t 0 Mzfo oorl adF reference antennas on 1978 Cougar [i \~~~8

ENGR-~~~~~~ F~L o ENG R. OPERATOR DATE./: ILE No..i.AV.LE#GTN TOWARDLOAD,4X,~~~~~~~~~~~~~~S.a\ o~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 45 ~~rJ~X ~5 5' ii At~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~/ ~~~~~ " ~~~~~~~~..'.:%,' ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ c 10.~~~~~~~~~~~~~'~' /"~ Fi gure A3 Impedance characteristics at CB and FM band frequencies for the Motorola antenna mounted on 1978 Cougar 186~~~~~

PARAMETER PERFORMANCE COMPARISON _...... [-;MOTOROLA _ FM STD. ENT. X/4 MONOPOLE FM PERF 88mHZ -2.58 0.0 93 -3.68 0.0 98 -5.95 0.0 103 -8.33 0.0 108 -9.16 0.0 CB PERF ch 1 -11.14 0.00 19 -9.51 0.00 40 -11.12 0.00 I FM VSWR! 88mHZ 2.08 1.82 93 2.85 1.63 98 4.56 1.33 103 7.33 1.53 108 9.53 2.64 CB VSWR ch 1 1.71 19 1.31 40 1.69 s ISOLATION ch 1 920m 19 720m 40 880m! AM SENS. 0.76mHZ -67 -64 1.10 -75 -70 1.6 -83 -79 AM - C 0.5mHZ 121.9 94.6 1.0 128.1 1 102.1 1.5 119.2 92.1 AM - Q'.M-Q22.21439 0.5mHZ 212.52 1463.96 i 1.0 213.83 j 1265.32 I 1.5 198.42 1 943.47 TABLE Al PERFORMANCE DATA FOR MOTOROLA ANTENNA ON 1978 COUGAR 187

UNIVERSITY OF MICHIGAN 3 9015 03525 1217