sencore sc61 problem

[peter g]

hi, I have a sencore sc61 that has a focus problem. there is very little service data on this vintage scope. however, I really like this scope and would like help in solving the bad focus problem. any help would be appreciated. thanks.

 

[betwixt]

It can only be due to wrong voltages on the CRT.
Does the focus control do anything?
Is the focus out over the whole screen?
Do you have a schematic?

Brian.

 

[peter g]

thanks so much for replying. i'am going to search to see if I can find a schematic. I agree its either a wrong voltage on the crt or a weak crt. will post back after the search. thanks again. pg

 

[peter g]

hi again, no, no schematic. looked all over. that is a bit of a problem. anyone, ideas.

 

[Roaburn]

Have you tried adjusting the "astigmatism" trimmer. It's the tiny one underneath the "Chan A" push button that requires the use of a small flathead. Also, what specifically happens when you adjust the focus knob? I attached a picture of a page from the Simplified Operating instructions that details how to use the "astigmatism" and "focus" to achieve your goal.

New here... so have 3 links to it using different methods.


<a title="ROABURN - WIN_20140828_213718.JPG" href="http://obrazki.elektroda.pl/3153813900_1409276692.jpg"><img src="http://obrazki.elektroda.pl/3153813900_1409276692_thumb.jpg" alt="ROABURN - WIN_20140828_213718.JPG" /></a>

https://obrazki.elektroda.pl/3153813900_1409276692.jpg

 

[peter g]

no I haven't tried that. but I will, will post back. thanks for help. pg

 

[peter g]

hi roaburn, I followed your suggestion and adjusted the astigmatism control and that solved my problem. thank you for your suggestion, also thanks to betwitch for his response.

 

[Roaburn]

No problem Peter. Glad I could help.