Re: Help with a TEK 502 scope

Dave Seiter

My first scope was a 502, and I really pushed the bandwidth, using it to look at waveforms on the Commodore PET and CBM computers.  It was actually the reason I joined the group too.
Unfortunately, I never did repair mine (I think the problem was the rectifier tubes), because too many other projects came up.

From: "" <>
Sent: Monday, June 11, 2018 7:12 PM
Subject: [TekScopes] Help with a TEK 502 scope

Hi to all,

I am new in this forum, a friend of mine tell me about a group of wise nice people.

I am restoring an old tek 502 tube scope. And I need some help: Its HV transformer is death, it has a burned winding and it makes sparks - really nice for a christmas tree but not for a scope, defenetely : (
I have been investigating a little bit and I realise that the CRT transformer of my TEK502 is indeed the same that the tek502A, it has 3 rectifier tubes instead of two. Maybe they change it at the middle of production time.
The rest of the scope is in good shape, its CRT is almost new, its power supply caps are like new as well and I change death tubes for NOS ones. So, lets say its like a brand new blind scope.

So I would need your help. From my point of view the options are:
          1. Buy a working HV transformer. If any of you have one and want to sell it, I am interested.
          2. Restore it. It is cover by wax, so it would be difficult not to break the little wires.
          3. Manufacturing a new one. I have no idea how many turns it has, wire diameter...

I am really interested in learning and, if possible, helping other forum partners. So, where do we start?

Waiting for your answers.
Thanks a million guys!!

PS. I do not know how to post images, if any of you say me how i will upload several pictures of the scope.

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