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Hey Carmine,
This isnt to bad of a problem to solve. Ive delt with it before. What youve got is a shorted electroytic thats for sure. Take a look at your schematic around the 6HE5. Youve got a 100uf @50V lytic from cathode to ground (C62 on schematic). If youve got a volt meter, take a voltage check at the cathode, pin 4. You should have 26volts right there if the cathode cap is ok. Also, while you're at it, take a voltage test of pin 10, you should have 280 volts. Comming to pin 10 are two electrolytics, C54 (10uf@475V) and C65 (30uf@475), this C65 is a combo cap inside a can, its the "squared" designation. Just follow the wires untill you find the lytics. But check your voltages first.
Heres how to test your capacitors. clip one of the cap leads out of the circuit, but be shure to clip near the middle incase you need to solder the wires back together should the cap be ok. Then, set your vom to RX1 test it with your meter, the needle should whip up and slowly fall back down, This indicates a proper working cap. Reverse the meter leads, the same thing should happen again. Should the meter fully deflect and stay that way, the capacitor is shorted and thats your problem. As for that C65, just test it by putting the probe on the capacitor lug and the other to chassis. If the meter fully deflects on rx1, its shorted. those caps are really easy to find on the chassis, they are the biggest capacitors and are held to the chassis by a metal band. Those caps are either black, and brown paper types, or they are orange and blue. Whatever the case may be, they will stick out at you when you open up the bottom cover. They will be in the middle of the chassis twards the row of user controls.
Hope this helps, It should get that set working again! As for finding new capacitors, go to "mouser.com" they have all the hard to find super high voltage electrolytics like those 475 volt things you've got to deal with. You'll probably spend about $5 a capacitor or less. I buy from them all the time. Its kinda tricky to learn there system but whatever cap you find is wrong, just let me know and I'll give you there part number for the right one as Ive got there catalog too.
By the way, my little photo caption is a 20Y1C48 copied out of a 1968 zenith brouchre!
Good luck-Let us know how it works out!, Doug
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