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Success! I have a stable picture now.
There had been some work around the transformer, T108 "Horizontal Sync Discriminator Transformer", a few capacitors were replacements. Could be that the caps still connected were leaky and someone previously has diddled that adjustment, trying to get the picture back in sync. The adjustment on the transformer was cranked all the way in. Since I had replaced all of the paper capacitors (leaving one previous repair which was a Sangamo 33M Mylar which tested good), it could be the reason that transformer was so far out of adjustment.
I have a very stable picture now with the horizontal hold control centered. I am using a 5AXP4 CRT temporarily whilst the Aquadag dries on the 10BP4. I still need to do some voltage readings, I have not checked the B+ etc. The HV is down to 5 KV instead of 9 KV. I just wanted to get the capacitors behind me.
I rebuilt (stuffed) 3 of the 5 can capacitors because the were leaking at below the working voltage. The other two were on value with no significant leakage at the working voltage for each section. I could tell that the two that were still testing good were manufactured by the same company (non marked BTW). The other three were manufactured by a different company as indicated by the type of construction. All three were the same company. Each capacitor was completely disconnected from the circuit and each section tested individually.
Whenever a resistor was disconnected on one end, it had to be right on value or I replaced it. Some were high but most were still within tolerance. Imagine that, since they were made in 1945-46!
I still have some issues to address.
- The focus control is all the way to one end. That's OK for the 10BP4 but not for the 5AXP4.
- CRT anode voltage is only 5 KV instead of 9 KV.
But I have a lot of good clean loud sound. I am using a DVD player feeding into a Blonder Tongue AM60-550 with rabbit ears on channel 8. The rest of the sets in the house pick up signals perfectly. Now, I have something to work with and refine.
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