[Amps] History of Grounded Grid Amplfiers

[Fuqua, William L.]

________________________________
From: Fuqua, William L. <wlfuqu00 at uky.edu>
Sent: Saturday, December 12, 2020 11:44 PM
To: Joe Subich, W4TV <lists at subich.com>; amps at contesting.com <amps at contesting.com>
Subject: Re: [Amps] History of Grounded Grid Amplfiers

The plate current meter in most AM TXs cannot be in series with B- side of HV power supply if it provides multiple elements and modulator.
Often the screen grid bias is provided thru a series dropping resistor from the modulated B+ and the modulator is also powered by the same power supply.

73
Bill wa4lav

________________________________
From: Amps <amps-bounces at contesting.com> on behalf of Joe Subich, W4TV <lists at subich.com>
Sent: Saturday, December 12, 2020 11:08 PM
To: amps at contesting.com <amps at contesting.com>
Subject: Re: [Amps] History of Grounded Grid Amplfiers

CAUTION: External Sender


On 2020-12-12 10:15 PM, Jim wrote:
 >
> I don't remember if AM transmitters were this way or not.

The RCA BTA-1R out in my garage certainly has the plate current
meter recessed (behind glass).  Schematic shows late current meter
in the B+ line to the finals (parallel 4-400).

73,

    ... Joe, W4TV

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