Recently I had opportunity to buy old Philips PE15xx series lab power supply in not bad condition for about $120, but I was too late and someone else bought it.
The seller praised its very low noise, low ripple, low output impedance and good voltage and current regulation. I took a look at schematic in service manual to see how "good old linear power supply" is built. This is schematic found in service manual:
It uses UA723CN and some old school BJT transistors. Datasheet says that UA723C with 5uF Cref capacitor has 86dB supply rejection. It looks pretty good for a part that cost about $1 (UA723CD).
From ua723 datasheet:
I thought I might try to build a similar power supply for education purposes. I'm curious how it would perform compared with cheap chinese linear power supplies.
Of course price of PE1542 includes also high quality terminals, case, meters etc., but for educational purposes rebuilding just circuitry could be interesting.
Is this (Phillips PE15xx) power supply really very good design? Or just my seller glorified it?
If it is - what can I use instead of ua723 and BDY (discontinued?) transistors to I build compareable low ripple low noise, good output CC/CV regulation power supply with modern parts?