I've had this Weir MiniReg 402 power supply for YEARS and it has been unbelievably useful. 0-30 volts at about an amp, regulated voltage or regulated current. My first job was with Mullards in Southampton and they had the enlightened notion that anything technical that was being scraped could first be offered to staff - it was working but slightly battered, and was mine for £5. That was a lot of money to me then (1968-9) as my first weeks wage was only £7 !
It has served me well, but a few years back the meter gave up the ghost. (Upper hair spring came detached from the armature) so in recent times I've always checked it's voltage with an external meter. Then the PSU gave up totally - no output. I got as far as finding a circuit for it, but then it just sat by my desk patently awaiting attention for at least six months.
Now I have an eBay search set up for these PSU as they are very handy, but most don't have the multi-turn voltage setting pot - just a single turn. However one popped up as 'spares or repairs' with the multi-turn pot. I won it for £13 intending to use it as a doner to get mine going, but when it arrived it was fully working

This shamed me into opening up my original one and doing a bit of fault finding. The meter issue was a badly tangled hair spring that was detached at the armature. Deadness was only a dry joint on the PCB and soon fixed, but what about the meter? It is a fairly standard 0-1 mA 45 mm square meter but actually not that common unless bought direct from China. CPC had a 0-500 micro-amp one in the same case size so I bought it intending to change the scale plate and put a shunt in it to bring it back to 1 mA sensitivity.
What they actually sent was a 45 mm square 0-30 volt DC meter comprising a 0-1 mA movement with an internal series resistor to give the range.
Time to pull a few bits apart and see what I can assemble from the parts: