HP-82104A Card Reader Repair Questions

[Papymouzot]

(03-28-2024 11:26 PM)teenix Wrote:  Do you have a copy of the service manual?

https://literature.hpcalc.org/items/396

Hi Teenix,

I didn't read this manual thoroughly before. I just read it again, taking more time.

Thank you for mentioning it, I initially missed lots of valuable information, it gives me new test opportunities.

The document schematics are valid for the two older (1980) readers I have. The more recent ones (1985 & 1986) have different pcb layouts. If one knows where to find the same document for the later card readers I will appreciate it a lot. I could not find it on hpcalc.org

Thanks to the available service manual I have now a complete set of information on what caps are on the circuits with their values for two readers. I am going right now to source the three capacitors from the sense pcb and also for the logic pcb and psu just in case.

I will come back after receiving the items... unless somebody else has more advice, and I will respond asap

Thanks again all for your help.
Charles