Cleanup, repair, and upgrade of a Hewlett Packard (HP)6200B power supply.

My old HP 6200B power supply was starting to have problems with excessive ripple and voltage regulation problems. I had a good idea of what the problem was before I even opened the case. What I didn’t expect was all the 4‑terminal electrolytic capacitors.
Several of the rectified DC filter capacitors were way out of tolerance electrically. I removed the 4‑terminal capacitors and replaced them with equivalent 2‑terminal capacitors along with an axial in C10.

I quickly ran into a problem in that the three negative pins connected to different parts of the circuit. The quick and easy way was to jumper the negative pads together to bridge the circuits just as the 4‑terminal capacitors did.
It would work, but I was not entirely happy with that solution.
I ended up with a labor intensive, but low cost solution to the problem.

The solution was a small 1″ diameter printed circuit board to adapt the new capacitors to the original 4‑terminal pinout, and allow the new capacitors to be mounted in the original aluminum capacitor shells.
The lead spacing on the PCB for the new capacitors is 7.5 mm.



The new capacitors easily fit into the existing aluminum shell with plenty of room to spare.
The two hardest parts of the process are carefully opening the cans and cleaning the old capacitor electrolyte out so that they can be reused .

I also used this process when working on my HP 6205C dual-output power supply.

OSH Park Capacitor triangle adaptor 15.5 base V1.1
Eagle CAD ZIP file Capacitor155triangle12.zip
Great write up. I have the same supply and think i may have bad caps, but i’m not sure. Power supply is only outputting ~3v at full amperage when a load is connected. Also tested in caps in circuit with an ESR meter and it measured lower than what i would expect on 3 of the 4, could bad caps cause this type of issue?
Thanks again in advance.
Hi Stephen,
Bad capacitors can cause all sorts of issues, depending on their failure mode.
If you decide to replace the caps with two terminal versions, verify all necessary negative capacitor pins are connected.
On several of the caps locations the negative pins act as a circuit jumper.
Another area that can cause mysterious problems is the rotary selector switch.
I recommend cleaning the switch with DeoxIT D5 contact cleaner, before any other troubleshooting.
Greg (Barbouri)
Thanks for the very useful info I just received my three pcb today boy that was easy thanks to you
What an awesome find! I was finally about to proceed with capacitor replacement on my 6205C that I have been delaying for years, when I came across your project page. Just ordered a set of 6 boards from OSH Park. Thank you so much for sharing your design!