Stan, Allow some variation to antenna variations also.
This on 15M, swr is 1.0:1 2W = 30W out 2.5W = 40W 3w = 50w 3.5w = 60w 4w = 70w 4.5w = 75w out 5w = 80w 5.5w = 90w 6w = 100w 6.5w = 110w 7w = 120w 7.5w = 130w 8w = 150w 8.5w = 160w 9w = 170w 9.5w = 180w 10w = 190w 11w = 200w 12w = 225w NOTE to ALL: This was not done with lab equipment or even a dummy load. This was measured using a K3 and a tri-band yagi and a cw tone. Gary On 12 May 2011 07:13, Al Lorona <[email protected]> wrote: > It's very easy to measure the 1-tone gain compression characteristics of an > amplifier. The desired result is a graph of Pout vs. Pin, with Pin on the > horizontal axis and Pout on the vertical. > > So what one needs to do is set Pin to the amp, and measure Pout into a > dummy > load. If you do this for several values of Pin, you'll be able to plot all > of > those measured points on the graph. It will look like a pretty straight > line > toward the lower Pin values, then it will flatten out (become more > horizontal) > as Pin (and Pout) get higher. > > The slope of the line is the gain of the amplifier. > > Very often the Pin values are 1 dB apart. One dB is about a 25% increase in > power. Meaning that if you are measuring Pin in Watts, then you can set Pin > to > roughly the following values: > > 1, 1.5, 2, 3, 4, 5, 7, 10, 13 Watts, etc., > > and measure the Pout at each value. The values should be converted to dBm > before > plotting. That's all there is to it. > > This is all done in CW mode. If you want to go further, you can go into SSB > mode > and apply two tones to the amp (which a K3 has the ability to do) and then > look > at the output of both the K3 and the KPA500 with a spectrum analyzer... but > I'll > leave that explanation for another day... or it can be found on the web. > > Al W6LX > ______________________________________________________________ > 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 > -- VK4FD - Motorhome Mobile Elecraft Equipment K3 #679, KPA-500 #018 Living the dream!!! ______________________________________________________________ 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
