[BC] WANTED - an FM tx.

[RichardBJohnson at comcast.net]

A properly designed grounded grid transmitter can still measure the current going to the final amplifier plate circuit when measuring the negative lead, even though the cathode (filament) contains both plate current and grid current. The metered HV supply negative lead is simply returned to the cathode circuit, not to ground -trivial.

Some companies were never able to figure that out!

Cheers,
Richard B. Johnson
Book: http://www.AbominableFirebug.com/

----- Original Message -----
From: "wpio fm 89.3" <wpio at gate.net>

WOW, interesting that the FCC had a lot to do with plate current getting 
measured in the hot lead.  Seems it's not as accurate to sample from the 
low side.  It was always a mystery how, CCA for example, knew what to 
set the variable resistor at because the grounded grid is getting some 
of that current.

My guess was that they temporarily put a DC current meter in the plate 
lead, and used that figure for the low side xmtr plate current panel meter.

Randy