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previous: Aron I've been measuring my bias current... -- 8/25/1999 5:18 PM

Re: Bias set too low?

8/27/1999 4:25 AM
jeff	Re: Bias set too low? Aron, the thing that really counts here is the idle current flow thru your output tubes - the bias voltage affects this as you know so for accuracy the "transformer shunt method" is probalbly the way to go ...BUTTTT watch out !! this method of measuring idle current requires you to be inside a live 440 plus voltage situation - and much more significantly - since it is CURRENT that can KILL you (.1 (one tenth of an amp of current passing throught your heart can kill you) whereas voltage will knock you you across the room (i been there) but a competed circuit thru your body containing a tenth of amp of current and enough EMF e.g. Voltage to push it through is curtains .... that is why the "1 Ohm resistor" mod is a good idea ... you read 35millivolts across the 1 ohmer and you have 35 milliamps of idle current ....

8/27/1999 4:25 AM

jeff

Re: Bias set too low?

Aron, the thing that really counts here is the

idle current flow thru your output tubes - the bias

voltage affects this as you know so for accuracy

the "transformer shunt method" is probalbly the way

to go ...BUTTTT watch out !! this method of measuring

idle current requires you to be inside a live 440 plus

voltage situation - and much more significantly - since it is CURRENT that can KILL you (.1 (one tenth of an amp

of current passing throught your heart can kill you)

whereas voltage will knock you you across the room (i been there) but a competed circuit thru your body containing a tenth of amp of current and enough EMF e.g. Voltage to push it through is curtains .... that is why the "1 Ohm resistor"

mod is a good idea ... you read 35millivolts across the

1 ohmer and you have 35 milliamps of idle current ....