zenith table top metal

[DaveWM]

20x1c36

pulled the HOT and the VOT did a slow power up, no issues, but the two lower B+ were non existant. Check the big 17w sand resistor on top, cracked. replaced it with a hollow tube 20w ceramic coated one, tried again but current went high on the metered variac right off, so stopped and checked the B+. 200 ohms on one one of the lower voltage legs, hmmm no wonder that big resistor cracked. traced the B+ around disconnecting here and there, all the way back to the pin cushion adj coil. It was ok so check the other side of the pin cushion, it went to a 6kT8 tube (part of the pic cushion) plate, which was bypassed to the ground with a .0033 blue disck cap.

hmmm this is odd the cap has what looks like a pimple on one side and a divot on the opposite. while watching the meter I squeeze the cap and the meter needle moves a lot. pull the cap and its shorted. replaced cap and B+ resistance goes to about 15k.

another slow start, all good this time current is nil (HOT and VOT still out) and filter caps are stone cold. so after about 1 hour of this slow ramp up, I decide to give it a go. HOT and VOT back in fast power up I hear the HV and then it all comes too life.

Color tint is too magenta, Talking it over Dan he suggest checking the phasing tube a 4 diode tube. Sure enough its weak on on and VERY weak on 3 other. Put a new one it and color is great, with full control of the tint.

while at it I check the other tubes, all test ok, I leave the IF tubes in order as I dont want to mess up the alignment. that pestky pincushion tube has a short in it (hmmm I wonder if there is a relationship in that short and that goofed up disk cap). Its also a burst amp tube so it may have been part of the color problem as well.

The vert is a bit jumpy, and it has a very slow hula on the right side. So I will prob have to pull the chassis and replace those HV tube caps in the vert circuit, and check my grounds. Oh and the tuner/controls need a good cleaning.