Let's have a quick look at this power supply I picked up at the Finger event. I have to admit, its mad scientist retro looks were a big part of its appeal to me. Plus I needed another lab PSU in my setup anyway and this fits in nicely. Linear supply with a big hunk of iron and copper.
It provides two 0-30V regulated and current limited rails, as well as an extra 5V rail. The variable rails are controlled by a SG4501J voltage regulator and an MC1458CPI dual op amp each. The pass elements are all TIP142 npn power transistors. The datasheet of the voltage regulator suggests a symmetrical application and states +-15 V capability. They run it for a 30V single rail.
Bun's Lab
It provides two 0-30V regulated and current limited rails, as well as an extra 5V rail. The variable rails are controlled by a SG4501J voltage regulator and an MC1458CPI dual op amp each. The pass elements are all TIP142 npn power transistors. The datasheet…
Despite having ten turn pots in the front, the rail only have single turn pots for adjusting the voltage and current when in current limiting mode.
The voltage control pots have a factor of three to them. The current limit pot on the left channel is 1x, but somehow the right one is 2x. The heck? I won't bother correcting this though without the schematics on hand.
The voltage control pots have a factor of three to them. The current limit pot on the left channel is 1x, but somehow the right one is 2x. The heck? I won't bother correcting this though without the schematics on hand.
The displays are self contained modules hera must have used in a number of their products. A local 7805 regulator - they run on 16V AC - a 741 op amp, a CA3161 BCD to 7 segment decoding driver and at the heart of it a CA3162 analog to digital converter for 3-digit multiplexed and BCD encoded output.
TIP140.PDF
55.8 KB
Datasheets
Bun's Lab
The displays are self contained modules hera must have used in a number of their products. A local 7805 regulator - they run on 16V AC - a 741 op amp, a CA3161 BCD to 7 segment decoding driver and at the heart of it a CA3162 analog to digital converter for…
They measure a voltage and that can be adjusted with this single and multi turn pot.
Everything tracks and displays correctly now. The old filter caps are still fine enough. I will still replace them though, once I get around to ordering them.