Arrived today from ebay, Systron-Donner PQ20-2.
Here I have a couple of 10r resisters on the rear connectors.
![](http://www.i2net.me.uk/files/TestEq/SystronDonner/PQ20-2 Front-02.JPG)
![](http://www.i2net.me.uk/files/TestEq/SystronDonner/PQ20-2 FrontDetail-01.JPG)
The Bad:
Absolutely zero information about this or most other Systron-Donner equipment on the internet so, if it doesn't work you are in trouble.
The Good:
Absolutely zero information about this on the internet so, not very popular and therefore cheap, very cheap £17 excluding shipping.
Not had much time to play with it yet.
The two units can be separated from the rack making for a smaller setup.
The voltage can be controlled by an external 0-10V source - maybe the current too.
The current limit works as a CC source just as one would expect.
The on/off switch is on/off so no way of presetting current but...
Those pots on the front are 10 turn so I could fit a couple of counting/vernier type dials, I have a couple lying around.
A quick look inside reveals what appear to be six silver-mica caps per unit. Now, I know very little about electronics, but I do know you don't scatter silver-micas around just looks, they are not cheap.
All in all, quite a cute little bugger
![Smiley :)](https://www.eevblog.com/forum/Smileys/default/xsmiley.gif.pagespeed.ic.R8GFI-pF6f.png)