Lord help me I just bought another friggin' power supply - an HP 6228B showed up on eBuy and like a fish to a lure I bit. ![Face Palm :palm:](https://www.eevblog.com/forum/Smileys/default/facepalm.gif)
It looks to be in decent shape and is fully shod. Should be here in about a week.
-Pat
That is a nice power supply. Congrats to your new member in your (constantly growing?) PSU family.
![Grin ;D](https://www.eevblog.com/forum/Smileys/default/grin.gif)
I have a diy power supply, based on an article in the German electronics journal elrad from Nov. 1985.
![](https://www.eevblog.com/forum/chat/show-your-favorite-and-mostly-used-benchtop-psu/?action=dlattach;attach=287789;image)
It has two channels (+/- 50V, 2.5A per channel) but it is suffering from oscillations, when the CC mode kicks in beyond 600mA.
![](https://i.imgur.com/dgZsBps.png)
This weekend I'm attacking the oscillation by applying some ferrite beads to the base of T2/3 T102/103 and some
Miller caps (1nF @ T1/101, T4/104). Also increasing 4 feedback capacitors of four OpAmps (LM324N) from 470pF to 10.47nF
(C3/4 and C103/104). I hope, this will calm down this otherwise very nice linear power supply.
Ah, and adding some LED illumination for the meters.
![Cool 8)](https://www.eevblog.com/forum/Smileys/default/cool.gif)
I've linked in below the complete article, including schematics, layout and parts list, if you want to have a closer look.
https://elektronik-bastelei.de/schematics/1185/Doppelnetzteil_gesamt.pdf