UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post - Tektronix 2211 scope short-circuited

MrBungle · 10th Apr 2019, 9:53 am

This happened to my 2235 recently. They do like to explode!

The power supply on these is mostly the same as the 2225 if I remember correctly, so have a look at the service manual for that (available free from w140.com). Check the input board carefully (the vertical board in the rear). It's chock full of RIFAs. Those usually go first. After that it's likely the secondary caps after the big toroidal transformer. The HT on these doesn't usually fail violently but that transformer doesn't look particularly healthy. I would buzz everything out.

You can actually bring these up on a DC power supply with enough volts just by jumping the secondary cap. This is handy for debugging!

Edit: there be dragons. I spent upwards of £40 on bits for my 2235 before I got it going again and now it has an HT problem

10th Apr 2019, 9:53 am	#2
MrBungle Dekatron Join Date: Jun 2016 Location: London, UK. Posts: 3,687	Re: Tektronix 2211 scope short-circuited This happened to my 2235 recently. They do like to explode! The power supply on these is mostly the same as the 2225 if I remember correctly, so have a look at the service manual for that (available free from w140.com). Check the input board carefully (the vertical board in the rear). It's chock full of RIFAs. Those usually go first. After that it's likely the secondary caps after the big toroidal transformer. The HT on these doesn't usually fail violently but that transformer doesn't look particularly healthy. I would buzz everything out. You can actually bring these up on a DC power supply with enough volts just by jumping the secondary cap. This is handy for debugging! Edit: there be dragons. I spent upwards of £40 on bits for my 2235 before I got it going again and now it has an HT problem