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500kHz QTX PA input 120W output >100W

The  QTX  designed by Ron GW3UEP   can give 100W output at very high efficiency  but you have to tune L3 for maximum output. Untuned  the output can be less then half of maximum.
Tuning is very easy using a ferrite bar.


i use the IRF540   and  the IRL540  the last one is an improved version it gave about 5% higher output.


Amazing performance  this MW QTX   n > 90%  imagine  a high power PA with such performance.
 1000W out would be 1800W  with same input ...
Only non linear modes   and low bands  helas..


http://groups.google.com/group/uk500khz/web/gw3uep-cw-tx

 received often in 2010
http://www.qsl.net/pa0oos/VX9MRC 500kc/vx9mrc_500_18jan.mp3
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