> ** In Class A, there is no grid-current, so all of the exciter power
> flows into the grid terminating resistor. If there is no 50-ohm grid
> termination, your radio will likely be in a state of vexation.
>
> > The input is untuned and unswitched, fed directly to
> >the grids of the 8122s thru a .01uF cap. Looking at the datasheet for the
> >8122, the control grid appears to be pretty tough
This is not the case. RF is fed into a 50 ohm load network composed of
C16 L2 and R6. The 8122's produce 20 db gain, increasing the 100mw
RF input to 10 watts to drive the pair of 4CX1500B's. The 8122's operate
in class A with 500 volts on the plates.
The answer to your question is that a 100mw exciter will do no harm to
the 8122's. The Harris RF-110A is an engineering marvel, designed to
mount in the bowels of a ship and pretty well take care of itself.
(((73)))
Phil, K5PC
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