Wanted: Tek CPS-250 P/S Schematic & Calibration Info - Page 1
Forum section: electronics / testgear

author: radiotek
author_rank: Contributor
timestamp: July 29, 2013, 03:21:49 pm
content: Looking for someone who can share the schematic and calibration procedure for a Tektronix CPS-250 power supply. Any help would be greatly appreciated.

author: Unknown
author_rank: Unknown
timestamp: July 29, 2013, 04:12:20 pm
content: These were made by a low-end Asian manufacturer and sold under the Tektronix name. Tek never released official service documentation for these, I think even the guy who ended up fixing these for Tek under contract (their repair department didn't have the necessary information to fix it) only had some notes and maybe partial schematics he had drawn up himself. Trying to find the guy referenced inthis threadmight be useful. Don't count on finding a full service manual, though.

author: radiotek
author_rank: Contributor
timestamp: July 30, 2013, 01:24:12 am
content: The service manual is available on ebay for $17.00 but I only want the schematic or the calibration info.

author: Unknown
author_rank: Unknown
timestamp: July 30, 2013, 07:48:34 am
content: I may be wrong, maybe they did publish schematics for their power supplies in their line of commodity test equipment, unlike the counters and function gens (eg. cfg-250, cfc-250) in the same line. The eBay auction does not show any schematics, though, although it suggests that they are included.The eBay auction for the service manual shows one page of the adjustment section of the service manual, you may be able to infer the rest of it from the circuit board. It's not like it's going to be a terribly complex circuit with dozens of interacting adjustments.

author: radiotek
author_rank: Contributor
timestamp: August 30, 2013, 03:21:20 pm
content: Even though this is a lower priced power supply that was manufactured by Tektronix it was still very was designed and well built. I opened it up and it saw that it was extremely well made and had high quality components and also had a very heavy duty transformer that looks like it could handle 10 or more amps. It also has a very complex circuit with 13 adjustments pots for performing a precision calibration. If anyone has the schematic and calibration info it would be really appreciated.

author: NilByMouth
author_rank: Regular Contributor
timestamp: December 27, 2015, 01:49:29 pm
content: Did you get the info you needed? I recently bought one of these power supplies and ordered the service manual from ebay.Malcolm

author: schenkzoola
author_rank: Unknown
timestamp: October 17, 2017, 01:39:58 am
content: Sorry to resurrect an old topic. I recently got one of these power supplies for a song, but it turned out to be a basket case (every one of the voltage regulator IC's was of a different manufacturer). I could sure use a copy of the service manual if somebody has it.I was able to find a poor quality copy of the schematic online, and got the power supply running, but it seems the current limit isn't working all that well, and the B channel fuse blows when switching between series, parallel, and independent modes.

author: schenkzoola
author_rank: Unknown
timestamp: November 10, 2017, 03:46:37 pm
content: I have finally found the cal procedure for this. Here are the links to what I have found so far.The cal procedure can be found here (registration required):https://www.mods.dk/manual.php?brand=tektronixA low resolution scan of the schematic can be found here:http://designideas.cocolog-nifty.com/.shared/image.html?/photos/uncategorized/2014/01/15/cps250.jpgThe user manual is in the usual place:https://www.tek.com/cps250-manual/cps250-user-manualIf anybody has the full service manual and would be willing to share it with me, I would greatly appreciate it!

author: edavid
author_rank: Super Contributor
timestamp: November 10, 2017, 05:35:03 pm
content: Here are the files mentioned by schenkzoola, for ease of downloading.

author: schenkzoola
author_rank: Unknown
timestamp: November 10, 2017, 06:29:45 pm
content: edavid,I wasn't sure if posting the files directly would violate the forum rules. That's why I just posted links.Thanks!