[AMRadio] AM Transmitter Advice??

W5OMR/Geoff w5omr at satx.rr.com
Sun Feb 19 02:55:22 EST 2006

John E. Coleman (ARS WA5BXO) wrote:

>I have heard rumors of a citation or two but only in extreme cases such as
>10 or 20 KW PEP and I don't know if the rumors are true.
>As I understand it the trick, that the FCC was to prevent, and someone was
>trying to get away with, was to run a 304TL with about 100 Volts on the
>plate in a GG configuration.  Forward bias it to a high plate current like 1
>Amp, so that it acts like a switch that is on.  Then drive it with 5 KW PEP.
>It may have been some other some scenario as this but I think you get the
>An Now, For Something Completely Different. 
>	Then there was the trick that a gentleman up in 3 land, I think, was
>going to run the high level double sideband reduced carrier generator type
>rig but he was not reducing the carrier just increasing the SBs via an extra
>upside down tube, as it was commonly called.  The sideband power would
>continue to go up without distortion (if copied on a proper synchronized
>product detector) after the first tube was over modulated in the negative
>direction. The voltage and power would be diverted to the upside down tube
>where sideband power would continue.  There was trouble with the specific
>rule interpretation at the time in the FCC. Of course any of us today, would
>be able to see that the upside down tube's audio plate current and audio
>voltage must also be counted as part of the input power.  But the FCC was
>having trouble deciding, at least as I understand it.  At any rate, I think
>they got him for being outside the 40 meter band limits.  You may remember
>more of the specifics on this Don.    
>John, WA5BXO

Fred, I believe.  W3PHL.

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