Fran, it's almost impossible to get a decent power reading by measuring the RF voltage at the load unless the load has a very, very low SWR. No common SWR meter is capable of showing when your load is well enough matched to give you any significant accuracy. That is, a small mismatch that won't hardly cause your SWR meter to wiggle is enough to cause very serious errors in your power measurement.
The sensitivity of most SWR meters drops with frequency too, so 80 meters is usually the least-accurate band! The simple fact is that it does not make one whit of difference whether the load shows an SWR of 1:1 or 1.2:1 to a decently-designed transmitter, so SWR meters are not designed to show you that difference accurately, but it can make a big difference in the RF voltage across the load. You really, really need a good non-reactive 50 ohm dummy load for these tests. Ron AC7AC _______________________________________________ Elecraft mailing list Post to: [email protected] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
