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Model 60 Rectifier Circuit - Printable Version

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Model 60 Rectifier Circuit - Bob - 07-09-2013

Am working on a Mod 60 using schematic #164. Put in new electrolytic caps, and rebuilt the filter condenser bank. Checking the voltage across Cap 46 I see 260vdc, across Cap 45 is 40vdc. Is this correct? The transformer AC volts check okay. Also checking the plate volts of the 6A7 pin 2 to pin6(K) I see nothing should be 250vdc. I don't understand what K means.
Thanks for any help
Bob

RE: Model 60 Rectifier Circuit - Arran - 07-09-2013

Any tube pin marked as "K" generally means cathode, that's often used as a reference point for checking voltage since it's the closest point to ground potential in the circuit.
Regards
Arran

RE: Model 60 Rectifier Circuit - Radioroslyn - 07-09-2013

Hi Bob
Not sure what diagram you are using? Can you post a link to it? Typically K stands for cathode in regards to tube connections. You aren't going to find any HV there, look for P would be the plate. That's where the HV should be.
Terry

RE: Model 60 Rectifier Circuit - BrendaAnnD - 07-10-2013

Read the OP again. He's saying that he's measuring from the plate of the 6A7 (pin 2) to the cathode (K, pin 6), between which should be 250V, but he is seeing no voltage there.

As far as his power supply voltages, I would check the bias resistor (47), and then the field coil on the speaker. No voltage at all to the 6A7 plate could be a shorted capacitor (20) or possibly an open 1st IF coil or resistor (9).

RE: Model 60 Rectifier Circuit - Bob - 07-10-2013

Thank you everyone. These tips are (will be) a great help. Won't be able to get back to the radio for a day or two. I will post what I find.
Bob

RE: Model 60 Rectifier Circuit - Bob - 07-14-2013

Making some progress. Replace Cap 8 and now have around 220 (not 250) volts on the plate of the 6A7. All I get out of the speaker is static whenever I touch the meter to pin 6 and the plate pin2.
I now have 350 vdc across cap 46 and 240 across cap 45. The speaker coil and resister 47 appear to be good. Is the difference between the voltages correct, or should they be the same.
What would be a god next step?
Bob