Since I have a couple of DRSI cards type 1,2,
I have done repairs on both of them and had good luck with substitution
of parts and have reworked them a couple of times.
Seams the worst problem I have had with them is the trigger-diodes
and the pnp,and npn small transistors replacing all chips found
on the market will do a better job a better TNC signal.
Note: The SCC chips should not be changed unless they are de-characterized or broken.
Here is a list of parts and research venders ,they may not be there but if you are trying to find parts for your card or card's check out the List.
****DRSI TNC-1 PC*PA CARD***
Part List..
Chips:
1. (u7) Motorola IQBD or 1458C or 8904
2. (u13) Texas Instruments SN75188N or 8904
3. (u2) ? 20 post..probley a nad gate.
4. (u10) Texas instruments SN74HC14N or Malaysia 8913EN
5. (u6) Motorola MC74HCO4AN UMAK8909
6. (u14) Texas instruments TCM3105JL or 8850pr or taiwan8284117
7. (u5) SCC Z8530AB1 or 28909 {sgs Thompson}
8. (u6) CIO Z8536AB1 or 28848 {try calling 1-617-259-0300}
9. (u4) SGC M74HC32B1 or 98737
10. (u1) DRSI 1989 P/N P0016
========================================================
TRANSISTORS
1.(q1) NVN 10KM T848 (three leg w/heat sink on top) FET s/w
2.(q2) ITT 3904
========================================================
CAPACITOR: electrolytic
1.(c1) 47 of. 16volts DC. {mfg. TKNT}
========================================================
LED: (red/green)
1. (d5,d3) green
2. (d4,d6) red
========================================================
TRIGGER DIODES: (orange w/blk./stripes) [TRY PHONE 1-800-538-5000]
(d7) 1N1822 :
(d8) ITT850 :
(d9) ITT 731 :
(d1) ITT850 :
(d2) 1N47 /52A
========================================================
CRYSTALS: OSCILLATOR (Y1) =(FOX0443 4.433619 MHZ.. KOREA
(XD1) RXD-1100 4.915200MHZ..
========================================================
POTENTIOMETERS:
(r11) 10k (260-10 Haiti 8901
(r10) 10k same
------------------------------
ceramic potentiometers :
(r14) 3329P-913F-401
(r15) 3329P-913F-401
========================================================
try JDR Micro or 800-356-0259, Deco Electronics,
1-800-423-4499,1-800-877-0072 (Rydel co.)