I actually have this **broken link removed** power supply.
A Powermate BPA 40D. I do have a paper manual. It's 40 V, 2A and uses two 723 regulators. I messed it up by reverse feeding it. The only issue I had/have is the I/V slide switch needing to be replaced. The fan runs all the time. It has course/fine for voltage and there is an engineering change order to change the voltage pot to 10 turn.
I also have a BelMerit PS501 that is 30 V, 3A with course/fine current controls and a digital switchable I/V meter. No schematic. It uses 723 regulators. It has indicators for CC/CV.
I also have both a precision 4 quadrant voltage and current source from Keithley. The current source is dead.
This handbook from HP is well worth reading
https://www.davmar.org/pdf/HP-AN90B.pdf
I would probably prefer dual meters.
This
https://www.djerickson.com/p1hack/ page is interesting.
he other one is a +5, +15, -15 supply that was part of some OEM system that used a 723 regulator.
In reality, you have to decide what you want. You have constant current/constant voltage and constant voltage/current limit. Most power supplies are of the constant voltage/current limit variety.
4-quadrant supples operate in all for quadrants like an amplifier. They can source voltage and sink current at the same time.
At the high end of stuff is the Source Measure Unit.
Then there is the "Electronic Load". It can operate at constant V, constant I, constant power and constant R.
I also have a "selectable" 0-32 v supply at 10 A that I picked up for $15.00. It's selectable because, you have to change the transformer tap depending on voltage. It's cool because a short on the output leads reduces the voltage to nearly zero. it's nominally set for 13.7 V.
You have to decide what you need.
This
https://www.circuitspecialists.com/programmable-bench-power-supply-csi3645a.html is respectable, but no service info is provided.