Microelectronics | Adaptec AHA-1542CP SCSI Controller

Synopsis

I bought this SCSI controller somewhere around 2005 for an MS-DOS server that I was running back then. It worked for a couple of years, then I retired it. Since then, it has stayed in the drawer next to an Adaptec AHA-1542CF SCSI Controller. Now, I plan to use with a new DIY retrocomputing project: an MS-DOS server!

Disclaimer
This article is not to be treated as a do-it-yourself tutorial on how to fix, restore, rebuild, or improve this unit. This was not my initial intention. But you can consider this whole content as a general guideline, should you decide to attempt any service procedure on an identical or similar unit.

The entire documentation is just a reflection of my work and I cannot be held responsible if you damage your unit, or even harm yourself in the process.

Maintenance

I thought about replacing the few electrolytic capacitors scattered on the PCB assembly. Unlike the AHA-1542CF SCSI controller which has both 10 uF and 22 uF capacitors, this one has only 22 uF / 25 V parts. As before, I went with single-ended conductive polymer aluminum solid capacitors. Everything went straightforward.

Pictures

Here are some pictures that I took during this operation.

New capacitors installed.

That was easy.