[Elecraft] KPA-1500 power reading?

Jim Brown jim at audiosystemsgroup.com
Sat Feb 6 15:28:33 EST 2021


On 2/6/2021 12:05 PM, Ray wrote:
> Trust the Wattmeter Only if it is seeing a 50 Ohm Dummy Load.

Bird slugs have a tolerance of 5% of full scale, and the reading is only 
valid into a 50 ohm resistive load. The LP100A is 5% of the reading at 
any power level and into complex loads (i.e, not only 50 ohms 
resistive). Years ago, Electraft used an LP100A for final test of their 
rigs. Don't know if they still do.

About five years ago, I bought W6OSP's LP100A from his estate and added 
a second coupler for my SO2R station, and had both calibrated at his 
factory. It auto-switches with signal from the amplifiers for the two 
radios.

73, Jim K9YC


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