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previous: Ed I was having a problem with 60hz & ... -- 9/22/2004 11:29 PM

Re: DC Heater Wiring

10/3/2004 4:23 PM
Brutus	Re: DC Heater Wiring Just a word of caution. If all you did was convert the fil voltage to DC and add a capacitive input filter then you just jacked up your filament voltage 30-40%. A good way to burn out your tubes prematurely. DC on fils is a great idea and certrainly is one of the best ways to reduce 60hz hum. However it is rarely used because of the voltage problem described. Some people blow off the extra voltage by using a series resistor, others through a small variac, others by using a lower voltage external fil xfmr. If you did none of these things then you are probably over heating your filaments. Brutus

10/3/2004 4:23 PM

Brutus

Re: DC Heater Wiring

Just a word of caution. If all you did was convert the fil voltage to DC and add a capacitive input filter then you just jacked up your filament voltage 30-40%. A good way to burn out your tubes prematurely.

DC on fils is a great idea and certrainly is one of the best ways to reduce 60hz hum. However it is rarely used because of the voltage problem described. Some people blow off the extra voltage by using a series resistor, others through a small variac, others by using a lower voltage external fil xfmr. If you did none of these things then you are probably over heating your filaments.

Brutus

Replies:

Bruce /Mission Amps Using a DC rectifier in the 6.3vac ... -- 10/3/2004 5:34 PM