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Old 08-03-2024, 10:14 AM
fumplet fumplet is offline
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Join Date: Apr 2023
Posts: 161
sound still goes low and high but not totally off. I replaced the two 15k ohm resistors in the audio section since my replacement had measured 14k and also the 14k resistor measured 19 k. Focus is now back, will see how long it stays. the voltage drop across the 15k to ground was measuring 25 volts before now its 155 volts. 15k to ground I put in there is 5 watts and it does get hot. When I turn off the set it gives a louder audio buzz for a second, not sure thats normal, but doesnt do it all the time. Basically still has weird gremlins hiding here and there.
If I pull any of the video tubes other than the first video tube, the sound gets much louder. Just pulled the 2nd video tube then put it back in and sound went almost out, then adjusted sound I.F. cans and got sound back but different position of 1st I.F. can slug. Its as almost as if these I.F. cans are iffy in adjustment.
YAYYYYYY. I think I found it. The 1st I.F. CAN terminal that goes to ground and a 330 ohm resistor if you move the terminal you get loud or soft sound. I dont yet know if I have to remove the can, replace the 330 ohm.resistor or what. CAn I remove the square shield, or does the can need desoldered and removed.
Going to assume the capacitor inside this can is 30 pf, schematic does not say. but has to be pico farads. I have zero guesses as to how accurate the 30pf has to be. the 2nd I.F. can has a 35pf in that according to schematic.
I have disc caps at 10pf. 3 of those would be 30 but dont know if temperature would make them change value or not. If not then I will just have to settle for a trimmer cap till I get correct ones and I might as well replace that 35 pf cap too.
Well, stuck 3 of the 10pf caps inside the can. Works and no crackly junk when the terminal of the 1st I.F. can grounded/330 ohm resistor to the 2nd audio I.F. tube anymore is moved/wiggled and I bet nothing will disturb it.

Last edited by fumplet; 08-03-2024 at 06:38 PM.
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