Tech-Master NIB TV Kit #5516

[Crist Rigott]

Here is what I used instead of the cork they supplied with the kit.

It is a very close cell foam that I get at Hobby Lobby. This is about 1/16 thick. I used some spray contact cement to glue them in place.

I also used the same stuff on the "inside" of the CRT strap so there isn't any metal to glass contact.





I also made a "stand-off" from 1/16 phenolic sheet to help manage the HV lead from getting too close the the chassis and the lead from the fly-back to the HV rectifier.

[Crist Rigott]

There was a post either in this thread or on the other forum, suggesting that I might need some more filtering. Well I clipped in another 220uf cap parallel with C43B. There was no change to the B+ supply but the picture seemed a bit more stable. Hmm..... so I added another 220uf to C43A and again the B+ stayed the same abd the picture remained stable.

So if I add these E-caps to each C43A and C43B it will bring each up to 440uf. Does anybody see anything wrong with doing that? Would a lesser uf work?

I'm including a picture of that section of the schematic.

[Crist Rigott]

I've been doing some investigating the focus problem I had with the help of another person offline.

Basically I cannot duplicate the focusing problem I had before I repaired the broken wires on the CRT.

If it was a broken wire I should be able to duplicate it by disconnecting pin 6 from B-. When I do, the picture remains in focus! NOTE - On the schematic, the blue wire from pin 6 shows it goes to chassis ground. This is an error on the drawing. It really goes to B-.


I've tried disconnecting wires on pin 2 and pin 10 with the same results, It still stays in focus. I even went back to the kit supplied 25CD6 and still stayed in focus.

I'm at a loss as to what caused the focus problem. I do know that after I fixed the the broken wires and reattached the base, the CRT stays in focus.

I'm including a section of the schematic so you can see what I'm talking about and maybe offer some reasons or suggestions.