THE UNIVERSITY OF MICHIGAN INDUSTRY PROGRAM OF THE COLLEGE OF ENGINEERING INSTRUMENTATION FOR THE ANALYSIS OF THE PROFILE OF MACHINED SURFACES Radomir I. Silin J. R. Frederick December 1966 IP - 759

TABLE OF CONTENTS Page LIST OF TABLES................................................ v LIST OF FIGURES............................................ vii 1. INTRODUCTION.......................................... 1 2. ALTERNATE METHODS FOR DESCRIBING A SURFACE..................2 Amplitude Distribution,..............................2 Bearing Area....................................... Profile Length........................................ 5. DESCRIPTION OF THE INSTRUMENTATION.......................... Method of Tape Recording the Signal...................4 4. OPERATION OF THE ANALYZING CIRCUITS.........................7 Amplitude Distribution................................ 7 Bearing Area......................................... 10 Profile Length...................................... 13 General Characteristics............................. 13 Scanning Time......................................... 3 5. RESULTS OBTAINED ON MANUFACTURED SURFACES................... 14 APPENDIX - Cricuits and Components.............................. 17 iii

LIST OF TABLES Table Page 1 List of Transistors, Diodes, Resistors for Circuit of Figure 11...............,,,,,,,,,,,,,,,,,,,, 19 2 List of Capacitors and Switches for Circuit of Figure 11.,,...................................... 20 3 List of Transistors, Diodes, and Resistors for the Circuit of Figure 12............................... 22 4 List of Capacitors, Switches, and Meters and Lights for Circuit of Figure 12............................... 23 5 List of Transistors, Diodes, Transformers, and Capacitors for Circuit of Figure 13................... 25 6 List of Resistors and Switches for Circuit of Figure 13........................................... 26 7 List of Transistors, Transformers, Diodes, Resistors, and Capacitors for Circuit in Figure 14,.,............. 28 8 List of Transformers, Transistors, Diodes, Resistors, and Capacitors for Circuit of Figure 15,............... 30 v

LIST OF FIGURES Figure Page 1 A sinusoidal surface profile has the same arithmetic average roughness as one with cusps..................... 1 2 Histogram or frequency plot of the distribution of amplitudes of a rough surface............................ 2 3 Block diagram of the apparatus for determining bearing area, amplitude distribution and the true length of the profile of a rough surface,.......................... 5 4 Photograph of Complete Apparatus. Proficorder is at left and X-Y1-Y2 plotter is at extreme right. Special circuitry is in cabinets at the left of the plotter..... 6 5 Pulse-Width Modulation. A triangular carrier wave-T (approximately 1000 cps) is combined with the signal to be recorded-S, to produce a series of pulses-P, of varying width.................................... 6 (a) Shape of a single asperity, (b) Pulses generated by scanning the asperity in (a) (c) Pulses generated at P1 correspond to amplitude Al. Pulses at P2 correspond to an amplitude A2. Amplitude is zero at lowest valley.............,,** 9 7 Amplitude distribution across the grinder marks of a surface ground steel specimen. A small length of the surface profile is shown at (a); total length included in analysis is 6 to 7 times as long. Analysis with short time constant as at (c) gives greater detail but is not as smooth as with long time constant. The distribution curves should be normalized so that the area under them is equal to unity............................. 11 8 (a) The profile of an asperity being analyzed for bearing area. (c) Pulses generated as shown at P1 are proportional in width to the bearing area at Al, and similarly those at P2 are proportional in width to the area at A2.. 12 9 (a) Bearing area, (b) amplitude distribution, and (c) the actual profile across the tool marks of a facemilled surface.,.,,,,,,,,,,,,,,,, *,,*,,,,.,. 15 10 Amplitude Distribution, long time constant only, for four specimens......................................... 16 vii

LIST OF FIGURES Figure Page 11 Modulator-Demodulator, Switching and Filter Circuits.. 18 12 Profile Length and Surface Roughness Circuits......... 21 13 Bearing Area and Amplitude Distribution Analyzer Circuit................................... 24 14 Power Supply for the Circuit in Figure 12............ 27 15 Power Supply for Circuit in Figure 13,.............. 29 ix

1. INTRODUCTION The specification and control of the surface texture of manufactured products is an increasingly important problem. This is due to the close relationship between the surface texture and the manufacturing process, and to the fact that the performance of the product in service can depend on the characteristics of its surface. At the present time the limit of surface roughness to be permitted on a manufactured part is specified as the arithmetic or root-meansquare (rms) average distance, h, in microinches between the peaks and valleys on the surface. This method tells nothing about the actual profile. A sinusoidal surface could give the same reading on a roughness meter as a surface which consisted of a series of sharp cusps as shown in Figure 1. However they can be expected to have quite different mechanical properties. Figure 1. A sinusoidal surface profile has the same arithmetic average roughness as one with cusps. -1 -

2. ALTERNATE METHODS FOR DESCRIBING A SURFACE It has been suggested by Poseyl and Pesante2 that a more meaningful way to describe a rough surface would be to plot a histogram or frequency plot of the distribution of the amplitudes of a rough surface. Amplitude Distribution A histogram can be made by dividing the range of values of amplitude into a large number of equal increments and then determining the fraction of the time the profile amplitude falls into each of these increments. This process is shown in Figure 2 for a typical rough surface for a small number of increments. In actual practice the number of increments is much larger and their width is simultaneously decreased. If a smooth curve is drawn through the maximum values of the histogram, a frequency curve for the distribution of the amplitudes of the surface is obtained. Corresponding Histogram Surface Profile - Figure 2. Histogram or frequency plot of the distribution of amplitudes of a rough surface. Posey, C. J., "Measurement of Rough Surfaces," Mechanical Engineering, Vol. 68, pp. 305-306, (1946). 2Pesante, M., "Determination of Surface Roughness Topology by Means of Amplitude Density Curves." Presented at the Annual Meeting of CIRP, Sept. 4, 1963. -2 -

-3 -Bearing Area Another technique that is useful in describing rough surfaces is that of plotting the variation of bearing area with the height above the lowest surface valley. The bearing area, at some uniform height above a reference plane, may be defined as the sum of the cross sectional areas of the surface asperities at that height. A convenient way to specify the bearing area is as a percent of the total area of the surface being analyzed. Profile Length A third characteristic of surface texture that is of interest is the true length of the profile of the surface. This quantity can exceed the apparent length by a factor of two or more and hence may be of interest in such applications as adhesion or heat transfer. Instrumentation has been designed and built at The University of Michigan to obtain values of these three parameters. namely, the amplitude distribution, the variation of bearing area with height. and true profile length. A description of the equipment and some results obtained on manufactured surfaces are presented below. 3. DESCRIPTION OF THE INSTRUMENTATION The instrumentation consists of standard devices such as a Proficorder* for obtaining an input voltage which is *Micrometrical Manufacturing Company. Ann Arbor, Michigan

-4 -proportional to the profile height. a tape recorder for storing the signal so it can be played back and analyzed, a triangular function generator. an X-Y1-Y2 recorder; and special units which were designed and built in order to perform the desired analyses. A block diagram and a photograph of the apparatus are shown in Figures 3 and 4[ respectively. Complete circuit diagrams with the values of the components are included in the Appendix. The output of the Proficorder corresponding to a short length of the surface to be analyzed is recorded on an Ampex FM100 tape recorder at a tape speed of 7-1/2 in/sec by the use of a technique called "pulse-width" modulation which is described below. A loop of tape is then played back repetitively for scanning purposes at four times the speed at which it was recorded. The signal that is played back is scanned over a range of profile heights and an analysis of amplitude distribution and bearing area is performed. The results of the analysis are displayed on an X-Y1-Y2 recorder. Method of Tape Recording the Signal The signal from the Proficorder is "pulse-width" modulated before recording it on the tape recorder in order to overcome the basic limitations of recording on magnetic tape. This method was found to be successful after attempts were made to use "instrumentation" tape of high quality of AM and on FM tape recorders. Although an FM tape recorder is shown in the photograph, it is possible to use a simpler and less expensive recorder. A principal requirement

-5 -Stylus Proficorder - Profile Ia~~~~~/=_~~~~ _Length Rough Surface 0 Surface Roughness (Triangular Wave Generator) Oscillator Modulator Record Tape Recorder (Loop) Playback Amplifier Filter Amplitude o Distribution O X-Y1 Recorder (Analysers) < Bearing - Area 0 X-Y2 Recorder Figure 3. Block diagram of the apparatus for determining bearing area, amplitude distribution and the true length of the profile of a rough surface.

I'. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~...... ~..t;'~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~..... e (1 0 9);f e. (1) |:~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~::~ -'. ~ ~0.........~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~......... ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~: ---?......... d)(......~ ~~~~~~~~~~~~~~~~~~~~~~~~~~:~..:..:.::... k:,t ~ —:: ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~............. t.~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~.-..., g).... g) ~ ~I 0................... ('"i ~~~~~~~~~~~~~~~~~~~~~~~~~....................... (t~ cfl H' 0 2:: F~~~~~~~ ~ ~~~~~~~~~~~~~~~~~~~~~~~~~~..,":...... (P ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~d ~ ~ ~ ~ ~ ~ ~ ~~~~~~~~~~~~~~ i::iii t...5 '`~ ~:~:::::-:..,~: H',~.~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~......... H, k~ ~ ~ ~ j1'"0 }~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~.-.......... t~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~...t........ t-"t (.p ~.~i~,i.:.::i~i.:j~i~ii~i;:i~i:::::i:..... t.~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~.......... J~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~.......... (0 - i i all (fl::::.i ~ ~ ~ ~ ~ ~ ~ ~ ~~~.... O~ t t.''..i'j ~1) iM ~-'-"b: 0i) 1! ds. ~0 -:::'::' *n a c'~~"t" t d ~" ~ Cn.~."..'...:-:::::-:_:i-:- —::_i~ii-. FJ0,~: _::r::...............:......... r:~~~~~~~~~~~~~~~~~~~~~~N ~~~~~~~~~~~~~~~~~~~~~~~......!i":.i r~~ ~cl,............~; ~ ""~"~""~"~""~. c~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~-, -3~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ l i -d i:~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~- '~i~~i.:;:i:;i: I I) I<I' r~4C+: -CI:.:::j::i-_~:::... ' ig~~~~~~~~~~~~~s cj-~~~ 0,.,,,~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~...... C'' KS~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 1~~~~~~~~~~~~~~~~~~~~~~~~(P '''~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~ ~ ~~~~~~~~~~~~~~..... C'~" 'N ~~~~~r fu gp:..~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ i: ~ ~ ~...... 1/....1.. p.... "9"' 3::~~~~: " ',~....-I X~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~..... cD i~~~~~~~~~~~~~~s

-7 -is that an increase in speed of at least four times be obtained on playback in order to obtain satisfactory filtering on integration. Pulse-width modulation is obtained by using the modulating signal to "chop off" the peaks of a triangularly shaped carrier signal, the frequency of which is chosen to be more than 10 times larger than the largest signal frequency that is to be analyzed. The resulting wave with sloping sides is converted to a square wave of variable width. The width of each square wave is proportional to the amplitude of the modulating signal as shown in Figure 5. Demodulation is accomplished by integration of these square waves. 4. OPERATION OF THE ANALYZING CIRCUITS: Amplitude Distribution The technique of analysis is as follows. A linearly increasing ramp voltage from an oscillator operating at about 0.003 cps is added to the demodulated signal from the tape loop. The sum of these voltages is used to activate a Schmidt trigger. The "trigger" is designed to "turn on" when the combined input signal reaches a pre-determined input voltage and to turn off when it drops below that voltage. During the turning on and turning off process, a series of pulses is given off, the number of which is determined by the slope of the profile at the "turn-on" and the "turn-off" points. During the turning on and turning off process the trigger generates pulses for a short time, the number of which depends on how rapidly the profile is changing as shown in Figure 6. If the profile

-8 -T PLi TIME Figure 5. Pulse-Width Modulation. A triangular carrier wave-T, (approximately 1000 cps) is combined with the signal to be recorded-S, to produce a series of pulses-P, of varying width.

-9 -A2 A1 0 4-) m 'r max -P 0 + 0 A2 I~ (a) o AA Parallel to Surface Amplitude - Amax Profile A2 A1 P Width Proportional to Number of Pulses Time (c) Figure 6. (a) Shape of a single asperity, (b) Pulses generated by scanning the asperity in (a), (c) Pulses generated at P1 correspond to amplitude A1. Pulses at P2 correspond to an amplitude A2. Amplitude is zero at lowest valley.

-10 -is steep, only a few pulses are produced. If the profile is nearly flat, more pulses are given out. The number of pulses produced as the profile is scanned at a particular amplitute (the amplitude is determined by the position of the "gate-" or "ramp-" voltage) is therefore proportional to the rate of occurrence of that amplitude over the profile being analyzed. These pulses can be summed by suitable integration techniques and automatically plotted over a range of profile amplitudes from 0 to maximum. This is then a graph of the amplitude distribution of the surface profile. A typical plot for a ground surface is shown in Figure 7. Bearing Area Bearing area is obtained by integrating the series of square waves that is obtained from the same Schmidt trigger that gives the amplitude distribution data. A square wave is produced by the Schmidt trigger as it turns on at a specified height when the profile being analyzed increases in height and off at the same height as it decreases after going through a peak. The width of each square wave is a measure of the cross sectional area of the asperity at the particular profile height which activated the trigger, as shown in Figure 8 (a) and (b). Integration of these pulses gives an output signal that is proportional to the ratio of the bearing area to total projected area at a given profile height. By scanning over the range of profile heights from zero to maximum, as is done in obtaining an amplitude distribution curve, a bearing area versus profile height curve is thus obtained, Figure 8 (c).

-11 -10 MicroincLes 0 o 02" air { (a) Ju p m e I I,D a^ I 1 (ya — 1 80 microinches - -- 80 microinches -- (b) Long time constant (c) Short time constant Figure 7. Amplitude distribution across the grinder marks of a surface ground steel specimen. A small length of the surface profile is shown at (a); total length included in analysis is 6 to 7 times as long. Analysis with short time constant as at (c) gives greater detail but is not as smooth as with long time constant. The distribution curves should be normalized so that the area under them is equal to unity.

-12 -I0 Profile Amplitude -go max c1001oo (a) (b) A max A 3 2 A5 (c) Figure 8. (a) The profile of an asperity being analyzed for bearing area. (c) Pulses generated as shown at P are proportional in width to the bearing area at Al, and similarly those at P2 are proportional in wid t th e tt ea area at A2.

-13 -Different time constants can be selected during the analysis in order to vary the amount of detail that is obtained in the display. Longer time constants produce smoother curves. Profile Length Profile length is obtained by performing an integration on the signal obtained directly from the Proficorder. It is not necessary to record and analyze the signal as is done for amplitude distribution and bearing area. An additional meter for indicating the average profile roughness is also provided. General Characteristics In order to obtain more satisfactory conditions for analysis, the Proficorder stylus unit was speeded up by a factor of 2.85 by changing a drive gear.* The function generator supplying the triangular wave for the pulse-width modulation had no special characteristics. It could readily be replaced by a simpler built-in circuit at less cost. Its output amplitude should be enough so that it is about 50 percent larger than the maximum profile signal. Scanning Time The circuit that is described requires about six minutes to scan the profile. A tape loop about 72 inches long is used. Care *Original tracing speed was 0.005 ips. or 0.125 mm/sec.

-14 -should be taken to remove from the loop any section of tape that did not contain a signal because it lay between the erase and record heads. A reset switch S4 on the analyzer unit is provided to return the ramp voltage to zero when it is desired to start a run. 5. RESULTS OBTAINED ON MANUFACTURED SURFACES Some typical amplitude distribution and bearing area curves are shown in Figures 9 and 10. It is apparent from these that wide variations are possible. Hence, in attempting to control or specify a surface, a. significant improvement might be made if limits were set beyond which any deviation from a standard curve would not be acceptable. However, the significance of the differences in relation both to processes and to service characteristics must first be determined. It is planned to use these techniques of analysis in trying to close the gap between process "causes" and product "quality," to the extent that the latter depends upon surface topology. Figure 9 shows the bearing area and amplitude distribution curves for a profile trace across the tool marks of a face-milled steel surface. The peak at the right of the amplitude distribution curve reflects the relatively broad cusps of the tool marks. Figure 10 is typical of the broad range of configurations reflected in amplitude distribution. The peak at low amplitude was caused by grooves worn in the slightly used surface of the clutch disc.

-15 -100 -, Id Amplitude ~ Amplitude O _ / / / /(Ai _ 2 5m in, ____ ____ ____ ____ ____ ____ ___ (a) (b) Figure 9. (a) Bearing area, (b) amplitude distribution, and (c) the actual profile across the tool marks of a face-milled suace actual profile across the tool marks of a face-milled surface.

-16 -(a) (b) L A (c) (d) Figure 10. Amplitude Distribution, long time constant only, for four specimens. (a) Lapped Surface (b) Carbide Faced (Across tool marks) (c) New Clutch Disc (4) Slightly Worn Clutch Disc

APPENDIX Circuits and Components -17 -

Signal D.C out to J (Meters) i. J l 1 I I 1J4 P~~~~roficodel. 1~~~~~~~~~_ Record ~Wave Generator Prouicodlt A l l 1\ l -_ C > l A =1 s 1 IJ | Tapef Recorder L R R Figure 11. Modulator-Demodulator, Switching angud Filter Circuits. Signal in R3 R7 R8 [1^^ — 1 1 R 12 Playback J5 J2 C C =9 C7 C6 __ 13 C1Q _ 5 c ~- ------ ---- -- - ---- --— I ----, ^; Tape to Recorder _n 19 17 O 15 O-1 (To S2 2 S2 Analyze-rs) O Signal 1 Tape from Recorder out 20 R16 R j R16 14 ~3 R~4 2r2 TR-7 TR-5 TR_R22 _ R27 T Figure 11. Modulator-Demodulator, Switching and Filter Circuits.

-19 -TABLE 1 LIST OF TRANSISTORS, DIODES, RESISTORS FOR CIRCUIT OF FIGURE 11. 1) TRANSISTORS Symbol Type Symbol Type TR-1 2N404A TR-5 2N404 TR-2 2N1302 TR-6 2N1302 TR-3 2N1302 TR-7 1N3028 TR-4 2N2148 2) DIODES Symbol Type D1 1N3028 3) RESISTORS Symbol Ohms Symbol Ohms Symbol Ohms R1 10K R10 5.6K R19 10K R2 5.6K R1l 10K R20 5.6K R3 1K R12 10K R21 10K R4 10K R3 1K R22 1K R5 300 R14 5.6K R23 10K R6 1K R 10K R24 8.2K R7 5.6K R16 5.6K R25 2.5K R8 5.6K R17 10K R26 200K R9 5.6K R18 5.6K R27 5.6K

-20 -TABLE 2 LIST OF CAPACITORS AND SWITCHES FOR CIRCUIT OF FIGURE 11. 1) CAPACITORS Symbol Farads x 10-6 Symbol Farads x 10-6 C ~220.0 C9 0.22 C2 100.0 C10 0.047 C3 0.0047 C11 0.22 C4 0.022 C12 0.47 C5 0.01 C13 0.022 C6 0.1 C14 0.1 C7 0.01 C15 0.47 C8 0.047 2) SWITCHES Symbol Type S 3PDT S2 5 gang switch, 5 position

- R25 \RS5 R TR -4 (Profile Length SectionS" 1- 5 s T -2TR1 TR-1 D INPUT to i 1-a S _ i'Sl-b TR SiD4 GR 2 2 - u 27 R4 6 R7 R8 -79 (Roughness Section D6 Rl1 ris T 1 12 2 Figure 12. Profile Length and Surface Roughness Circuits. Figure 12. Profile Length and Surface Roughness Circuits.

-22 -TABLE 3 LIST OF TRANSISTORS, DIODES, AND RESISTORS FOR THE CIRCUIT OF FIGURE 12. 1) TRANSISTORS Symbol Type Symbol Type TR-1 2N404A TR-5 2N404 TR-2 2N1302 TR-6 2N404 TR-3 2N404A TR-7 2N1302 TR-4 2N404 2) DIODES Symbol Type Symbol Type D1 1N34 D6 1N2069 D2 1N34 D7 1N2069 D3 1N34 D8 1N2069 D4 1N34 3) RESISTORS Symbol Ohms Symbol Ohms Symbol Ohms R1 12K R9 2.7K R17 4.7K R2 1K Ro1 2.7K R19 500 R3 5.6K R1 100 R20 1.8K R4 1.5K R1 4.7K R21 250K R5 3K R13 1K R22 2.5K R6 100K R14 100K R23 2.2K R7 100K R15 470 R25 100 R8 2.2K R16 4.7K R26 620 R27 100K R28 680

-23 -TABLE 4 LIST OF CAPACITORS, SWITCHES, AND METERS AND LIGHTS FOR CIRCUIT OF FIGURE 12. 1) CAPACITORS Symbol Farads x 10 C1 1.0 C 100.0 2 C3 50oo. C4 100.0 c5 50.0 2) SWITCHES Symbol Type S1 3PDT S2 SPST S3 SPST S4 SPST S5 SPST 3) METERS AND LIGHTS Symbol Type G1 profile length meter 0 - 50 ma G2 roughness meter 0 - 50 ma L1 GE NE 51 (Pilot Light)

B U T7 R8 9* TR-5 BR38 Input C TB - T- R14 TR - 4 Signal from R b IR R 4 J151^^ ^ 2 T T18 37 42 F D 2 16 R C4 R '2 a 0 -b4o JLO ~ ~ ~ ~~~~~~~~10 15 "17 2a2 - Input Rl 5 6 1 C 5 R1 6 C R19 0 r2- e -------- R -------------------------------------- -X-OUT 21 -r D ~~~~ -10 R 0*32 R22I C7 2'3~ 7~~~~~~~~~~~~~~~~~~~~~~~~~~~ TR-6 R TR-9 -t 24 2~R7 TR -8 4 R EBA - Y OUT, BEARING AREA R2 31 R23 TR-1~ R25 R "~3 h R54 AD - Y OUT, ANPLITUIDE DIST. R 2,-5 R 'o.E2i J -— r B25 TB-73B2 28 50 X OUT, FOB X-Y1-2 BECORDER JR - TIANGULAR WAVE INPUT FOR MODULATOR Figure 13. Bearing Area and Amplitude Distribution Analyzer Circuit.

-25 -TABLE 5 LIST OF TRANSISTORS, DIODES, TRANSFORMERS, AND CAPACITORS FOR CIRCUIT OF FIGURE 13. 1) TRANSISTORS Symbol Type Symbol Type TR-1 2N396A TR-6 2N491 TR-2 2N396A TR-7 2N404A TR-3 2N1302 TR-8 2N508 TR-4 2N404A TR-9 2N396A TR-5 2N1302 TR-10 2N404A 2) DIODES Symbol Type D1 1N2069 D2 1N2069 D3 1N2069 3) TRANSFORMERS Symbol Type T1 H50 (United Transformer Corp.) 4) CAPACITORS Symbol Farads x 106 Symbol Farads x 106 C1 150 C7 1000.0 C2 220 C8 500.0 C3 20.0 C9 100.0 C4 20.0 C10 100.0 C5 20.0 C11 50.0 C6 100.0 C 50.0 12

-26 -TABLE 6 LIST OF RESISTORS AND SWITCHES FOR CIRCUIT OF FIGURE 13. 1) RESISTORS Symbol Ohms Symbol Ohms R1 100K R23 390 R2 24K R24 20 R3 108K R25 390 R4 15K R26 5.6K R5 8.2K R2 10K R6 8.2K R28 15K R,( 6.2K R29 8.2K R8 10K R30 680 R9 100 R31 500 R10 1K R32 8.2K Rll 5-1K R33 180 R2 2.7 K R34 2.7K R13 -4. 'K R35 16K R14 10K R36 27K R15 47K R3i, 10K R16 820 R38 1.8K Rli. 1-5K R39 16K R18 10K R40 20K Rl9 4. 7K R41 4-K R20 3.3K R42 100K R21 5K R43 100K R22 40 2) SWITCHES Symbol Type S1 3PST S2 DPST "on" short time. "off" long S3 SPST S4 SPST

R2 4 Ti TR-1 ~ ~ ~ ~ ~~~~T (^! D2 DB~~~~~~~~~ c 40v. C CD C Fus e 7 6 1 20v. D7 J (. ~~~~~110 volts C C4 4 A 3 R3 R4 3 6~~~~~~~~~~~~~~~~ 5 T2 -~ I a ---0 R R6 D6 4ov.,__o 25 jj O Fr 2igure r -nr - L —j ~ ~ ~ ~ ~ ~ ~ ~ ^ — -- Figure 14-. Power Supply for the Circuit in Figure 12

-28 -TABLE 7 LIST OF TRANSISTORS, TRANSFORMERS, DIODES, RESISTORS, AND CAPACITORS FOR CIRCUIT IN FIGURE 14. 1) TRANSISTORS Symbol Type TR1 2N2148 (RCA) 2) RESISTORS Symbol Ohms Symbol Ohms R1 1K R4 10 R2 10 R5 47 R3 100 R6 10 3) CAPACITORS Symbol Farads x 10 Symbol Farads x 106 C1 1000.0 C4 500.0 C2 500.0 C 1000.0 C3 1000.0 C6 500.0 4) DIODES Symbol Type Symbol Type D1 1N3028 D5 1N2069 D2 1N2069 D6 1N2069 D3 1N2069 D7 1N2069 D4 1N2069 5) TRANSFORMERS Symbol Type TI P4144 (MERIT) T2 P4143 (MERIT)

T1 2 40v. Ci~~ C D 2R7 - 1 - C3 D4A I Fuse — 2 D- 2 -C4 5 110v. A.C. R3 R4 D6 0, 4 l R5 40v O 5 6 7 A& 20 F7ig 5.7 r Figure 15. Power Supply for Circuit in Figure 13.

-30 -TABLE 8 LIST OF TRANSFORMERS, TRANSISTORS, DIODES, RESISTORS, AND CAPACITORS FOR CIRCUIT OF FIGURE 15. 1) TRANSISTORS Symbol Type TR1 2N1294 (RCA) 2) DIODES Symbol Type Symbol Type Symbol Type D1 1N3028 D4 1N2069 D7 1N2069 D2 1N3026 D5 1N2069 D8 1N2069 D3 1N2069 D6 1N2069 Dg 1N2069 3) RESISTORS Symbol Ohms Symbol Ohms R1 150 R4 10 R10 R 10 R3 240 R6 10K R7 built in 4) CAPACITORS Symbol Farads x 10-6 Symbol Farads x 10-6 C1 1000.0 C4 500.0 C2 1000.0 c5 1000.0 C3 500.0 C6 500.0 5) TRANSFORMERS Symbol Type T P4143 (MERIT) 1 T2 P4143 (MERIT) 6) LIGHTS Symbol Type L1 GE NE 51