[Elecraft] Calibrating the P3 Station Monitor?

[Peter W2IRT]

I'm good with about a 10% error (on the cautious side), and since I'm a contester, I want to ensure I'm never over about 1425 Watts when I'm competing. The Alpha 4510 was supposedly calibrated to known standards as well (for $1150 new it darned well better have been). I can live with it reading a tad high. However I was hoping to sell it to help fund my upcoming KP-1500 purchase, but the TX MON doesn't seem to be the solution, which is most unfortunate. I love what it does, but the accuracy is a problem.

 - pjd

-----Original Message-----
From: Don Wilhelm [mailto:donwilh at embarqmail.com] 
Sent: Thursday, July 19, 2018 6:35 PM
To: Peter Dougherty; Elecraft at mailman.qth.net
Subject: Re: [Elecraft] Calibrating the P3 Station Monitor?

Peter,

Realistic instrument errors are up to 20% - check the ARRL Product reviews.
It just seems your Alpha meter is off in one direction and the TX 
MONitor is off in the other direction.

See if you can borrow an LP100 wattmeter which has been calibrated by 
N3LP to NIST tracable standards.  That will provide you with an up to 5% 
error.  Larry is reluctant to specify the error any closer than 5%.

In this age of digital displays, we have a tendency to believe that the 
display is accurate down to the last displayed digit.  More often than 
not, that is not true.