The ARP 1016 Dual Noise/Random Voltage Generator was a fairly typical noise circuit utilizing a reverse-biased NPN transistor to generate avalanche noise. The output was amplified and output as "white" noise. It was also low-pass filtered at 6dB/Octave to get "pink" noise. Further filtering was done to get the random voltage output. Two of the circuit shown below were built on a single board.

SCHEMATIC - (click on image to download full-sized version)


Resistors1/4 watt, 10%, carbon composite
100 OhmR34, R35
220 OhmR36
1 KR32,R33
1.2 KR5
5.6 KR24
10 KR8
15 KR21
27 KR17
47 KR27
68 KR9, R10, R13, R14
82 KR18
180 KR6, R25
270 KR19
330 KR22
470 KR3
820 KR20
1 MegR28, R29
1.5 MegR1, R23
4.7 MegR4
PotentiometersLinear Taper
10 KR7, R26
Capacitors20%, 50 volt, ceramic disc
30 pFC6, C10, C12, C23
50 pFC8, C11, C21
100 pFC9
330 pFC13
.0033 uFC15 (3.3 nF)
.001 uFC14 (1 nF)
.01 uFC16 (10 nF)
0.1 uFC19, C22 (100 nF)
Capacitors20%, 35 volt, tantalum
1.0 uFC1, C2, C7, C17
10 uFC5, C18, C20
A2803-004-A *Q1 - Noise Select
TZ81 **Q2, Q3, Q5
2N5172Q4, Q6
Integrated Circuits
LM301AHZ1, Z2, Z3

* - an ARP part number, most likely a 2N5172. Not all 2N5172's are good as a noise source, so these would have been tested and selected.

** - TZ-81 alternate part was the 2N5249, also defunct. 2N3904 would be a modern equivalent. Also a 2N3906 would be the modern substitute for the TZ-581 (alternate 2N5367) that ARP used as the PNP complement to the TZ-81.

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