[Amps] GG amplifier input impedance

[Ron Youvan]

> Some of you are getting confused between the difference of the
> the impedance between the elements of the TUBE and the impedance of the 
> complete
> circuit.  He is referring to the grid to cathode impedance of the TUBE.

>    The cathode to ground impedance of a grounded grid amplifier involves
> the cathode grid and the plate.  This is quite different than the grid 
> cathode impedance
> of the TUBE.

   We aren't confused, obviously he didn't tell us what he was thinking about,
just like my XYL (wife) 90% of the time.

>> >    Grid to Cathode impedance of a tube
>> > is the grid to cathode voltage divided by the
>> > grid current!!!

>>    I wouldn't be so quick to say that.  Nothing is that simple.
>>    The load on a grounded grid amplifier is seen by the amplifier's 
>> driver.
>>   (I assume as long as the GG amplifier is drawing plate current)
>> A good percentage of the driving power winds up in the grounded grid
>> amplifier's load.
>>    You drive the cathode, the cathode is connected (through plate
>> current) to the plate of the tube that is connected through matching
>> networks etc. to the load.
-- 
    Ron  KA4INM - The problem with socialism is that eventually you run out of other people's money.
                  [Margaret Thatcher]