🚀 go-pugleaf

In article <26374@cup.portal.com>, ISW@cup.portal.com (Isaac S Wingfield) writes:
> 
> If the transmitter is a standard plate-modulated rig, the 5 Hz will
> certainly saturate the modulation transformer, with possibly dire
> results; the 20kHz will spill, provided you can get it through that
> same transformer...
> 
> Modulation transformers are big, heavy, and *expensive*. Rest assured
> that the manufacturer didn't use any more iron than was necessary to
> get down to 50Hz, nor pay any more attention to distributed capacitance
> than necessary to get to 10kHz. [...]

Slightly off the subject of the original question (re: improving the
transmitted frequency response), What _is_ the current practice in AM
transmitter design?  I am familiar with the classic plate-modulation
methods, but many years ago studied other methods such as using two
unmodulated carrier sources, phase-modulating them, and combining them to
yield an AM signal.  This had the advantages of not needing all the iron
of the plate-modulation schemes, possibly better efficiency, and better
fidelity.

Can anyone educate me as to the current state of the art?


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Paul M. Elliott      Optilink Corporation     (707) 795-9444
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