The GS35b has an indirectly heated cathode, tied to one side of
the heater. The connection from your bias circuit needs to go to
that point, not to the centre of the heater transformer. The way
you describe the connections, you're adding AC to the bias voltage.
Steve
> Ok .. do you really need the Mangeian Wire from the B- of the Filter board to
> the shunted amp meter?? I have my amp up and running with a GS-35b now and im
> sure that my bias isnt working right .... mabey it is ... but as it sits now
> ..
> i should have 30V bias keyed and im showing 60ma idle ... now this is why i
> think i still have a problem with metering - when driving with 30W im getting
> an output of 600W (carrier/cw -what ever) and the uA meter is showing only
> about 120 mili-amps of plate current.
>
> Second question is do you need plate voltage on the plate to complete the
> bias
> voltages (im talking through the tube) to the heater?? My DC at the heater is
> 120VDC cutoff and 4V DC key'd state (no drive). My Bias supply is not sagging
> and the collector of the pass transistor is tied to the center tap of the
> heater transformer ...... Please leave out comments about using a center
> taped
> heater transformer and the differences of using a bifilar wound rod for RF
> blocking - its simply what i have and plan on using for now.
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