Tektronix 556 and 565 restauration

[Ysjoelfir]

Hey everyone, yesterday I picked up a 556 and a 565 for 150€ each, including an 3A5, 3A7, 1A2 and 1A4 plugin. Today I tried both and noticed the following obvious problems:

556

• right plugin slot doesn't respond
• left plugin: the horizontal position only pushes the traces a few millimeters around
• switching the plugins doesn't move the error to the other side
• focusing isn't exactly the best
• that darkened mesh inside the front bezel is loose. Any suggestions on how to glue that back on?
• Many of those small plastik knobs from the toggle switches are missing

565

• traces doesn't show up at all, but dots are briefly visible while heating up - so at least the tube and HV are working kind of

I guess I will start with the 556 since it at least displays something which could help in finding faults.
I will post high res pictures as I go on working at those and keep you updated if there is someone interested

Any Ideas, comments and so on are always appreciated.

[Alex Eisenhut]

https://groups.io/g/TekScopes

[Ysjoelfir]

Thanks for the link, but I have to admit that I don't really understand those newsgroup style forums, so I think I won't be too happy around there.

However, I started with the 556. I started with some hours of cleaning work. That wasn't too bad since the scope has lots of room to go around with the brush, cotton swabs and window cleaner.
The plugins were cleaned under running water and being dried in the sun right now. Since I wasn't all to thrilled to disassemble the transformers from the main unit I decided to clean many things inside just with a dry brush or cloth - which worked very well. Also I glued the mesh from the front bezel back on, removed the crumbly dust which was once an air filter and lubricated moving parts as suggested by Tektronix in their lubrication manual.

While cleaning I also noticed a fault that will definitely influence the missing lower beam: The 6GF5 Compactron Tube is broken, so no wonder that there is no beam available.

Also I found some sprague paper caps which should be leaking by now, which could be a reason for the focus and position problems I encountered. We will see when spares arrive

I have attached some more photos to enjoy taking a look at this wonderful device. 

[GerryBags]

That looks in pretty good condition, at least like it was stored in the dry. Looking forward to watching your progress. I'd love to have one of these in my lab, beautiful machines! 

[Alex Eisenhut]

3A5? I'm very envious!