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reduce voltage
rghines1
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Posts: 190
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#10

03-18-2010, 08:13 AM
Agree with Ron saying that those caps should not have blown to begin with. Take some voltage measurements of the power supply again.

Concerning using a resistor to drop voltage. Assuming the average B+ current is approximately 80 milliamps and with a 1000 ohm resistor would drop 80 volts. Wrote earlier 100 ohms but that would only drop 8 volts which is not much. A 1000 ohm resistor would need to be 10 watts.

The resistor solution is not perfect since during warmup the voltage can still surge quite high. Rectifiers tend to warmup first before the other tubes are warm enough to start drawing current.
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Messages In This Thread
reduce voltage - by denver - 03-17-2010, 02:12 PM
Re: reduce voltage - by rghines1 - 03-17-2010, 05:41 PM
Re: reduce voltage - by denver - 03-17-2010, 05:50 PM
Re: reduce voltage - by denver - 03-17-2010, 05:54 PM
Re: reduce voltage - by rghines1 - 03-17-2010, 08:09 PM
Re: reduce voltage - by denver - 03-17-2010, 08:22 PM
Re: reduce voltage - by Ron Ramirez - 03-17-2010, 08:37 PM
Re: reduce voltage - by denver - 03-17-2010, 09:39 PM
Re: reduce voltage - by Carl Travis - 03-17-2010, 09:44 PM
Re: reduce voltage - by rghines1 - 03-18-2010, 08:13 AM
Re: reduce voltage - by denver - 03-18-2010, 01:58 PM
Re: reduce voltage - by rghines1 - 03-18-2010, 06:37 PM
Re: reduce voltage - by denver - 03-18-2010, 07:37 PM
Re: reduce voltage - by denver - 03-21-2010, 07:04 PM
Re: reduce voltage - by denver - 04-06-2010, 04:22 PM
Re: reduce voltage - by Ron Ramirez - 04-06-2010, 05:05 PM
Re: reduce voltage - by rghines1 - 04-07-2010, 09:28 AM
Re: reduce voltage - by codefox1 - 04-07-2010, 11:27 AM



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