120 or 240 volts supply? On Feb 4, 2012, at 2:27 PM, david park <contrast...@yahoo.com> wrote:
> I have recently assembled KPA500 serial number 641. When testing into a > dummy load I find that I get a large variation in the DC power input when > driving for 500W CW when I go from band to band. My worst band is 21MHz, > where I get the highest current (lowest efficiency). The drive was adjusted > to give 500W as indicated by the LCD display. Here are my results:- > > 1.8MHz DC current 10.0A fan hardly ever comes on > 3.5MHz DC current 10.0A fan hardly ever comes on > 7MHz 12.0A > 10.1MHz 12.4A > 14MHz 14.3A > 18.1MHz 13.8A > 21MHz 16.4A temperature rises rapidly and fan > soon gets to full speed > 24.9MHz 13.5A > 29.7MHz 12.3A > > I have no results for 50MHz band as I have no transceiver covering that band. > > The readings drift as the heatsink (and the dummy load) warm up, and so I > took readings quickly and allowed time for the heatsink to cool down between > each band. I find that the KPA500 current sensor tends to give low readings. > I would be interested in knowing how other amplifiers perform. > > David Park G3PSV > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
