Doug, "I would like to know if running 2/3, 1/2 or even 1/4 maximum power output increases reliability and MTBF."
I have no experience of amplifier design but I would expect reliability of the finals to depend on temperature. Finals temperature will depend on the power dissipated in the finals (PA dissipation) and the effectiveness of the cooling design. To understands finals dissipation one would need to produce one's own test data or rely on the work of others. My test data for the KPA500 shows PA dissipation peaks at about half power output. So far no one has disputed the validity of my test data. It is my understanding that running an amplifier at reduced power only reduces PA dissipation if the finals voltage is adjusted give a good load match for that reduced power condition. The KPA500 has no provision for adjusting PA voltage for the reduced power case. For reduced power the PA voltage is actually higher than for full power because the high voltage supply is not regulated. As I said, I have no experience in amplifier design and would appreciate comments from those who do. 73, Andy, k3wyc ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [email protected]
