[BC] AM Plate Modulation Concept

[Robert Meuser]

No, Richard.

200% modulation is what it says. Ask the many broadcasters who operate between 145 and 
165% modulation. The problem is of course in the negative direction where audio peak must 
be clipped at 100%. 200% positive modulation will have an upward baseline shift due to 
the asymmetry. You just need a big modulator. Hence the 5 KW TX with a separate 10 KW 
modulator and power supply.  More modern PWM and PSM transmitters have been built with 
such capabilities for over 20 years. 

R


On 21 Feb 2006 at 6:28, Richard Fry wrote:

> Tom Dimeo clip:
> >He says that the negative half cycle does not cut off
> >the carrier but he is able to get upward of two hundred
> >percent modulation in the positive direction.
> ___________________
> 
> Hams like to think in terms of peak envelope power instead of average 
> power.  The p.e.p. of a carrier with 100% AM is 4X its unmodulated value 
> (twice the PA current at twice the PA voltage).  That equals 200% AM to a 
> ham, maybe?  Just guessing.
> 
> RF
> 
> 
> 
> 
> 
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