Tektronix 2465 Oscilloscope repair - Page 1
Forum section: electronics / repair

author: OldSchoolTechCorner
author_rank: Frequent Contributor
timestamp: September 26, 2015, 02:58:31 am
content: Bought this and didn't power on and HV supply shorted. Look like someone was trying to repair it and forgot to hook the Tektronix crt anode connector and blew the HV side. As carbon where it sparked to top shield. Did clean it, so look a lot better then it did before.Also figure might as well change the capacitors in the power supplies, as had noticeable hint smell of fish. Quite a few were open and bad.X and Y capacitors were all cracked. Have to order a suitable X capacitor, so will change it later.These capacitors look like they seen better days.Now that what a bad capacitor looks like.Motor needed fresh oil, but will replace it with box type later on.You can see how hot this ran

author: OldSchoolTechCorner
author_rank: Frequent Contributor
timestamp: September 26, 2015, 05:00:33 am
content: Good new is it work for the most part. Still need work, as horizontal output IC is faulty, more like due to heat, due to fan was motor seize up. Spray cold air at it and works.Cracked and more likely brittle, so more likely going to convert over to regular fan and change back.

author: bitseeker
author_rank: Super Contributor
timestamp: September 26, 2015, 05:08:29 am
content: Nice job. That was quite the capacitor hell gallery.

author: matth
author_rank: Contributor
timestamp: September 26, 2015, 05:10:23 am
content: Out of interest, what do you think of the Peak ESR meter? Was tossing up where to buy one of these or one of the Silicon Chip kits.

author: SeanB
author_rank: Super Contributor
timestamp: September 26, 2015, 05:55:33 am
content: But the Peak, or go on eBay and get the $20 component tester along with it.

author: bitseeker
author_rank: Super Contributor
timestamp: September 26, 2015, 06:03:35 am
content: Has there been a comparison between the two? Doing searches with such generic terms hits all kinds of stuff.

author: OldSchoolTechCorner
author_rank: Frequent Contributor
timestamp: September 26, 2015, 06:10:01 am
content: Quote from: matth on September 26, 2015, 05:10:23 amIt a great tool so far beside a LCR meter, I like the peak due to it's size and get into tight spaces without issue, batteries last a long time. It measures large size capacitors and pretty accurate, but won't measure under 1uf capacitance. They also have a Semiconductor Component Analyser and is well worth getting to. Sometime they offer package deal with case even. You just have to watch for them.

author: OldSchoolTechCorner
author_rank: Frequent Contributor
timestamp: September 26, 2015, 06:18:02 am
content: Quote from: bitseeker on September 26, 2015, 05:08:29 amThanks.

author: Gyro
author_rank: Super Contributor
timestamp: September 26, 2015, 09:45:19 am
content: Nice comprehensive repair.Don't put off changing those Rifa X and Y capsWhen (not if) they go, they will leave a horrible smoky residue on your nice clean boards (the X cap will briefly emit flame!) and a nasty lingering smell. Once they start to crack then they suffer from moisture ingress, you're on borrowed time on this one, they're renowned for it.

author: OldSchoolTechCorner
author_rank: Frequent Contributor
timestamp: September 26, 2015, 03:59:12 pm
content: The Rifa caps are being replaced, already did the Y caps, just need to replaced the X caps, waiting for suitable replacement to come back in stock. Still have some work to do on this scope, as have to wait for new fan, new back, due to airflow, so has to be replaced with newer version back and have to wait on U800 Horizontal Amplifier IC to show up. Seem to be well with calibration on all channels. Just pointed fan to blow directly on U800 to get it to work long enough to test channels. May go though all steps in service manual, once repairs are finish.

author: Johnny10
author_rank: Frequent Contributor
timestamp: September 26, 2015, 07:05:07 pm
content: Great looking job for what it looked like to start!I don't think I have seen caps look so bad.You are the MAN !

author: AF6LJ
author_rank: Unknown
timestamp: September 26, 2015, 07:18:30 pm
content: Nice work and thanks for the peak inside...

author: FlyingHacker
author_rank: Frequent Contributor
timestamp: September 28, 2015, 03:33:01 am
content: My 2465 looked pretty much the same. The paper and wax box shaped line caps had actually burst open, though. All recapped an works like a charm. I also broke the collet on the fan as well.Fantastic old scopes, though. Much prefer CRTs over modern displays.

author: OldSchoolTechCorner
author_rank: Frequent Contributor
timestamp: October 01, 2015, 11:11:07 pm
content: Did finish rebuilding fan controller and socketed IC this time around. Needed to do some more work on HV side, turn out was one of the issues with screen distortion and loss of control. Was due to faulty resistor and cold solder joints. Scope now works great screen artifacting gone completely, even after running it for a hour. No more percussive maintenance needed. No more error codes.Just need new Y capacitors and fan and check calibration, go though service manual after all repairs are done and be able to use this for a while. CRT was replaced 2 years ago, so not very many hours on CRT, if any, as anode wasn't push in all the way and what blew the HV side in the first place, so hopefully will last a while.

author: OldSchoolTechCorner
author_rank: Frequent Contributor
timestamp: October 01, 2015, 11:27:06 pm
content: Just for those that want to know how to take the front trim off, as remember someone asking. It is in the service manual.The hidden screws are on top trim

author: AF6LJ
author_rank: Unknown
timestamp: October 01, 2015, 11:31:16 pm
content: Nice...

author: SoundTech-LG
author_rank: Frequent Contributor
timestamp: October 02, 2015, 06:42:29 pm
content: Beautiful. Great photos. With the capacitors as an exception... ugly there. Great job. Picked up a 2445 recently on the cheap. So that, and the 2467's, and a 2465BDV and all of these scopes need the power supply recap. Got to get these caps on order. Particularly the Rifas !! I had a Philips scope blow one up in my kitchen. I had to run outside with it!!! Nasty.