Products > Test Equipment

Need Help with Tektronix 500 series scopes

(1/3) > >>

Aperna1985:
Hi everyone,  I'm getting into tube radio and T  repair and bought two used scopes for $50 one is a 531A and the other is a 536.  When I then them on the fans run,  the relay clicks and the CRTs light up,  but I just get a Dot on the screen,  I can move it around by playing with the controls but I don't get the line I'm supposed to have.  Can anyone help me trouble shoot it?  I already tested all the tubes and they test very strong,  also both CRTs have been replaced.  I think these came from a laboratory the insides are squeaky clean and they have calibration and maintenance dates written on stickers inside them. 

AVGresponding:
1. Do they have the plug-ins inserted?
2. Are they set to X-Y mode?
3. Are they set to External Sweep?

Aperna1985:
Ok the 531A has a Type CA plugin,  which is inserted.  I've tried cleaning the contacts and wiggling all the tubes.  I tried turning the knob labeled triggering mode and it makes no difference between internal or external. If I turn the variable time knob I can make the dot wider, and the horizontal position knob moves the dot but that's it.  I've attached a picture. 

The other scope is a 536, I'll correct my first post.  That one has a dot that kind of shakes left to right.  No matter how I adjust the Vernier position or the vertical position I always have the left arrow and the down arrow lit.  If I switch to the 5x magnifier I get a little line that is biased to the left.  If I turn the time all the way up or down the dot stops moving.  You can see motion between 20 milliseconds and 5 milliseconds after that it just appears to sit still. 
The plugins in this one are type L and type 53/54T. 

Arts:
Have you checked for missing tubes? Happens regularly with old Tek scopes >:(

AVGresponding:

--- Quote from: Aperna1985 on May 31, 2023, 08:25:49 pm ---Ok the 531A has a Type CA plugin,  which is inserted.  I've tried cleaning the contacts and wiggling all the tubes.  I tried turning the knob labeled triggering mode and it makes no difference between internal or external. If I turn the variable time knob I can make the dot wider, and the horizontal position knob moves the dot but that's it.  I've attached a picture. 

The other scope is a 536, I'll correct my first post.  That one has a dot that kind of shakes left to right.  No matter how I adjust the Vernier position or the vertical position I always have the left arrow and the down arrow lit.  If I switch to the 5x magnifier I get a little line that is biased to the left.  If I turn the time all the way up or down the dot stops moving.  You can see motion between 20 milliseconds and 5 milliseconds after that it just appears to sit still. 
The plugins in this one are type L and type 53/54T.

--- End quote ---

Not the external trigger, the external sweep

Navigation

[0] Message Index

[#] Next page

There was an error while thanking
Thanking...
Go to full version
Powered by SMFPacks Advanced Attachments Uploader Mod