Image is of my HP 6284A(left), which is more what I expect from an HP PSU; a big heavy all metal lab supply and my HP (6215A) (right).
I like to buy vintage test equipment. Especially if something comes up for sale locally, which avoids the usually high cost of shipping boat anchors from eBay.
I was excited to see a vintage HP power supply come up for sale recently. A model 6215A. I immediately bought it since it was only a few bucks. This supply dates from 1969. Generally the HP kit I have from this era weighs a ton, with all metal chassis. The first thing I noticed when I picked this up was the all plastic case and the overall light feel. I then noticed the two knobs on the panel, which I assumed were the voltage and current adjustments were just fine and coarse voltage. I probably should have checked the specs first, but honestly I know when I see something like this I will buy it regardless. I would buy a brick with the HP/Agilent/Keysight logo if It was for sale on the cheap.
When I got the unit home I immediately took it apart, I was surprised the entire all plastic case was simply held together by a few plastic clips, not a screw in sight. This thing feels cheap. and unlike a lab grade supply the current limit is not adjustable. It has a fixed 500mA output. Reading the service manual I started to get the feeling as what this was for. It seems to be meant to be a cheap way to get a lot of supply rails in a rack mounted system, or production test environment. They sold racks to mount up groups of these. These were meant to be cheap and bought in large quantity, not really a bench instrument. It is interesting to me that even in the past they were using the same kind of cheap plastic clip together cases I frequently see in consumer devices today, especially from a brand I usually associate with high build quality.
However the electronics are of the usual quality, everything seemed in good condition, sans one failed electrolytic cap. After replacing that the supply fired up fine and even without adjusting the calibration pots the accuracy was dead on and the regulation was good. For something made in 1969 to still be good in 2025 despite spending the last decade or more in someone’s shed, shows quality. This unit still gets a place on my bench, quite often when I need multiple supplies 500ma is reasonable current limit and it works as well as the day it was made. I might sound like I have a negative impression, but it more that my interest was piqued by something different than what I expected. Frankly I am surprised I have not seen one of these before. If they were meant for cost sensitive, high volume application, you would expect them to be very common surplus items.
Image is of my HP 6284A(left), which is more what I expect from an HP PSU; a big heavy all metal lab supply and my HP (6215A) (right).