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Update/Comments on my set:
1. Received the 75 ohm 10 watt ceramic resistors for the heater circuits... they seem to be about the right value. At 125 volts line input, I get about 6.5 volts on the CRT heater, and pretty close to 6.3 volts at 117 volts line. Turn on surge at CRT heater is slightly greater than 8 volts, so I may add a TVS diode later, when set is no longer used with the variac. The resistors run quite warm, so I positioned them against the back of the HV cage and used a bit of heat sink grease between them and the aluminum surface. They now run under 200F.
2. Pulled off the front (indeed, I protected the speaker, as recommended) repaired the speaker (previously damaged by careless fingers) and replaced the rectifiers and power resistor (corroded wire fell off).
3. Finished up the caps (29 in my set) and replaced the electrolytics. (see pix). Picture has improved only slightly from previous photo, but is now stable.
4. Getting about 10.3 kV HV, other voltages are now at spec or slightly higher.
5. Bright spot on center of CRT lingers for nearly a minute after turn off... anybody have a mod to eliminate it ?
6. Next, check the tubes, upgrade if necessary, fine adjust horiz and vert size linearity, polish cabinet.
fun project!
jr
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