37-620 voltages

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37-620 voltages

RodB
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05-19-2020, 09:20 AM

The voltage on the 6K7 plate is rather high so changing 29 to 82K might be a good idea. The other B+ voltages seem to be OK. Measurement devices in 1937 had a wide range versus today's high impedance devices and today's higher line voltages throw them off even more. My philosophy is the pwr transformer is 70-80 years old and you will want to be as gentle as possible with voltages. So I put a dropping resistor in the primary to bring the voltage down to about 115.

Rod

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37-620 voltages - by loneddie - 05-18-2020, 09:15 PM

RE: 37-620 voltages - by RodB - 05-19-2020, 09:20 AM

RE: 37-620 voltages - by morzh - 05-19-2020, 09:37 AM

RE: 37-620 voltages - by RodB - 05-19-2020, 10:14 AM

RE: 37-620 voltages - by morzh - 05-19-2020, 10:35 AM

RE: 37-620 voltages - by RodB - 05-19-2020, 10:58 AM

RE: 37-620 voltages - by loneddie - 05-19-2020, 02:45 PM

RE: 37-620 voltages - by morzh - 05-19-2020, 02:51 PM

RE: 37-620 voltages - by loneddie - 05-21-2020, 04:39 PM

RE: 37-620 voltages - by Radioroslyn - 05-21-2020, 05:54 PM

RE: 37-620 voltages - by morzh - 05-21-2020, 06:18 PM

RE: 37-620 voltages - by Radioroslyn - 05-21-2020, 06:30 PM

RE: 37-620 voltages - by morzh - 05-21-2020, 06:42 PM

RE: 37-620 voltages - by Radioroslyn - 05-21-2020, 08:19 PM

RE: 37-620 voltages - by morzh - 05-21-2020, 08:34 PM

RE: 37-620 voltages - by Radioroslyn - 05-21-2020, 09:08 PM

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