HP 8161A Disassembly
The device looked like this initially (the top and bottom covers were missing):
The leftmost card is missing (it was already removed). The display is at the front.
From this position I am numbering the cards from left to right, starting at 1 and ending at 21. Card position 19 is empty (there is a slot on the front rails but not at the end). After removing all cards we are left with the empty chassis with number markers for all cards:
In the empty chassis picture you can see the bottom card mount being crooked; in fact its screws were missing, and it is slightly bent.
I removed all cards first, and wrote down all connections from card to card. For this I number all gold coax-like connectors on each card starting at 1 for the topmost one, and going downwards. Some cards have connectors in odd places so these are marked as such..
The device contained the following cards:
| # | Code | Description |
|---|---|---|
| 1 | 66518 | A18 BD AY Regulator |
| 2 | 66520 | |
| 3 | 66523 | Rep rate gen board (VCO) |
| 4 | 66526 | Time Interval Gen 0 to 9.9ns |
| 5 | 66527 | Time Interval Gen 10 to 40ns |
| 6 | 66528 | Time interval gen 50ns to 999ms |
| 7 | 66526 | Time interval gen 0 to 9.9ns |
| 8 | 66527 | Time Interval Gen 10 to 40ns |
| 9 | 66528 | Time interval get 50ns to 999ms |
| 10 | 66526 | Time interval 0 to 9.9ns |
| 11 | 66527 | Time Interval Gen 10 to 40ns |
| 12 | 66528 | Time interval gen 50ns to 999ms |
| 13 | 66526 | Time interval gen 0 to 9.9ns |
| 14 | 66527 | Time Interval Gen 10 to 40ns |
| 15 | 66528 | Time interval get 50ns to 999ms |
| 16 | 66554 | |
| 17 | 66552 | |
| 18 | 66555 | |
| 19 | * * * | Empty |
| 20 | 66552 | |
| 21 | 66553 | Damaged |
At the front (the backmost panel) is the CPU board of type 8161-66509.
The power supply contained the following boards:
| # | ||
|---|---|---|
| 1 | 8160-66511 | A11 BD AY Switching Regulator - Burned out |
| 2 | 8160-66512 | A12 BD AY Rectifier - Broken cap, leaking? |