At 03:28 PM 5/6/01 -0700, you wrote:
> >
> >Jim inquires,
> >
> >"A problem for all the experts-
> >I Built a 3-1000Z monoband amp for 10 meters. I Sowly Variaced it up
> >and it
> >seems ok at 1500volts. Put 3KV on it and it will make a few watts of
> >power
> >without even putting RF to it. I heard a small RF type arc- kind of like
> >slight arcing in an air variable, (I have a vaccum cap) the tube glowed
> >red...etc."
> >
> >Jim,
> >
> >Shouldn't you also be terminating the INPUT with a 50-ohm load?
> >
> >73, Roy K6XK/0
> >
>? only Class AB1 needs input termination.
>
>cheers
If no input is being provided it should be terminated with 50 ohms
or with the OUTPUT of an transmitter/transceiver set to
zero output. DO NOT have it connected to a transceiver which is in receive
mode while bringing up the B+.
If it does begin to oscillate it will fry the input of the receiver section
of your transceiver. That is why I prefer to use
a 50 ohm dummy input resistor when first bringing up an GG amplifier.
73
Bill wa4lav
William L. Fuqua III , P.E. EE
Department of Physics and Astronomy
CP 177 Chemistry Physics Building
University of KY
Lexington, KY 40506-0055
Phone 859 257-4155
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