Admiral 19A12 High Voltage Issue
I would really appreciate some assistance on increasing the high voltage on my Admiral 19A12. I'm currently only getting ~4.2kV. I do have an image on the screen, but it's pretty unstable. I'm assuming it's due to lack of HV. Per Rider's the normal HV output should be ~ 6kV range.
I have restored a Motorola VT-73 and a Predicta Debutante with good success, but I'm certainly not an expert. I'm sure I'm missing something obvious.
Here is what I have done so far:
* All (6) HV caps replaced with 6kV SHV brand caps from Just Radios
* All electrolytics replaced
* All paper caps replaced
* Most resistors have been checked
* All tubes have been checked
* Tuner contacts have been cleaned
* I have swapped the 1B3 twice & the 6V6 HV Osc. a couple times as well to no avail
* I have moved the feedback coil numerous times on the 1B3 with some improvement
* I replaced the 1300pF cap in the HV cage with one from another set (spot on)
* All pots have been cleaned
* I do have sound
* My B+ is a bit low around 215-220 (the Pi filter checks out fine and I swapped numerous 5Y3s to get the B+ to where it is now)
* I haven't swapped out the 7JP4 since I'm getting a pretty sharp picture at times
Thanks in advance for any help at all. This is getting a bit frustrating after a lot of work, but that goes with the territory on TV restorations:-).
Thanks,
Scott
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