[Amps] AL80B low power

[Carl]

>I was testing a used 3-500z and blew the swamping resistor in the filament 
>ckt.  I replaced this resistor and put my original tube back in the
> and it will only draw 300ma on the plate and 100ma on the grid.

There is no swamping resistor in the filament. Where was this located?

 The grid resistor  R28 in stby has +25V and goes down to 9.5V in xmit. I 
thought it
> should go to 0V.

The 25V is the standby bias and the 9.5 is the operating bias.


> I am trying to find out if the tube is gone or has something else gone 
> kapoot. I replaced Q2 and Q3 on the SWR board.
>
> The AMERTRON schematics leave to much hanging.  I wonder if anyone has 
> made a good schematic of the AL80B.
> Any advice as to what might be wrong with the amp would be helpful.
>
> Art  W3TZ

Never saw a good AL-80B schematic

Carl
KM1H

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