CTC-4 Director 21

[Electronic M]

Originally Posted by jr_tech

I think that this handy tip should have been made a sticky:

http://www.videokarma.org/showthread...hlight=degauss

jt

I've made it into one.

[dieseljeep]

Originally Posted by Electronic M

I've made it into one.

I picked up a Radio Shack bulk tape eraser, that works great! It's a black plastic unit, that looks like a travel iron. It's a real powerful item, that can be used to demagnitize, just about any kind of magnetic media. It also works well as a deguasser, even though, I still have the first RCA DG coil, I bought over 50 years ago.

[kvflyer]

I too use a Radio Shack bulk eraser. It is very powerful and does the job.

[SwizzyMan]

Put in the new crystal and things have improved I believe. The oscillator isnt running at the correct frequency as indicated by the lack of color sync. I dont see nearly as much interference anymore. I did blow out the hv cage with compressed air and moved 1 lead that was somewhat close to a solder joint. I'm not sure if I should adjust L127. Fine tuning isnt able to lock the color and neither is the color control. I think I may have to adjust L127 (reactance coil). Still have no red.

[SwizzyMan]

14 turns counter-clockwise on L127 made the rolling bars a lot higher, but I still cant get it to lock. I reverted L127 back to its original position. I need to hook up the frequency counter and see what the oscillator is running at.

[SwizzyMan]

I connected the frequency counter to the oscillator. It measured out at about 3.58MHz which was good. The target frequency is 3.57545 so I went off of that. The lowest I could get the oscillator by turning L127 (reactance coil) was 3.57970 which was plenty off. I think I need to add a cap in parallel with the 270 pf cap on the oscillator tank circuit. Your thoughts?