Sylvania tuner B+

[chipper]

I have a question about 130v and 255v B+ voltages used in a 58 model Slyvania model 21C501 chassis # 1-533-1 that need a replacement tuner, It uses 130 and 255 B+, I have a used tuner out of a Admiral set (about the same year as the Sylvania) But it only uses 130v B+ , so will it work as a replacement or do I need to find an exact part?

[Don Lindsly]

Tube filaments, current and voltage, mechanical fit, shaft length, etc are the first considerations. If it fits, connect the 130 line and don't use the 250 source.

[chipper]

OK: I do have a standard tv tuner model TV-2232 that requires(B+) 130v for the 6j6 mixer osc and 250v R.F. for the 6BQ7 rf amp, my chassis provides 120v and 255v b+ BUT a note provide with the tuner states for the 250v b+ It must be 250v and under for the tuner to operate properly, can I use a voltage dropping resistor to get the 250v needed, and if so what ohm and watt?

[Electronic M]

IF frequency is also a major consideration.

[Don Lindsly]

Chipper:

As Tom states, make sure the IF frequencies match first. If not, it won't work at all.

255 will work OK. That is close enough. Use a 470 ohm, 1 watt resistor if you insist on dropping the 5 volts. That will drop 10. It is not critical since you are not operating in a weak signal environment.

Don

[chipper]

OK: IF Frequencies: Can you tell me where I need to look to compare these frequencies?

[Electronic M]

The photofact for the TV should have the IF frequency listed, but unless you know which model the spare tuner came from I'm not sure how you would go about finding it's IF frequency.

[chipper]

OK: The sylvania set works at 39.75 mc (min) and the TV-2232 can only be adjusted between 19-26 mc. I replacement tuner for Sylvania is part #323-0064 for VHF models only Chassis #1-511-1 model 21C502. If anybody might have a spare tuner?

[Don Lindsly]

39.75 is a trap frequency. The IF is ~45 MHz. They don't match. It's over.