"gareth" wrote in message
...
Dear all,

Pardon my QRO ignorance, but always having been a QRP-ish person, but
why is there a grid current meter on high power amplifiers?

Is it to ensure that sufficient grid current is flowing to ensure that the
rectification produces enough grid bias?

Is it to prevent excessive grid dissipation?

Or something else?

Yours in blissful ignorance,

Gareth


Several reasons and it depends on the class of service and if grid or
cathode driven.

If grid driven it will tell you how much drive you have and if too much for
the tube. Also if you see any grid current while operating AB1 and ssb you
usually are over driving the amp and getting into distortion problems.

If cathode driven it is mainly to prevent over driving the grid of the tube
with too much power and burning it out.