[Elecraft] KX2 / WM1 Reporting Conflict

[John Oppenheimer]

Hi Jim,

Both the KX2 and W1 need to be calibrated to a standard. The W1 manual
4.5V is a rough calibration. As I remember, KX2's are calibrated at the
factory at some (I've forgotten) power level. Both the KX2 and W1 are
somewhat non linear.

For my shack, I've decided that a DL1, along with an accurate 10M Ohm
Fluke DVM is the standard. No adjustment required and is as accurate as
the 1% load resistors, DL1 diode drop voltage, and DVM accuracy.

John KN5L

On 9/30/20 1:46 PM, James Bennett via Elecraft wrote:
> Wondering if anyone can help on this - I’ve got a KX2 and W1 Power Meter. The power out on the KX2 does not match what the W1 is reporting. I have the W1 connected to my MacBook Pro displaying the serial data being sent to it.
> 
> I just verified that the W1 voltage at the TP1 connector is exactly 4.5 volts, per the manual. I ran the KX2 Manual Transmit Gain Calibration. The KX2 is showing exactly 6.0 watts into a dummy load, going through the W1. The serial data reported by the W1 is 7.20 watts, consistently. Also, the KX2 firmware is the most recent.
> 
> So, who is wrong - KX2 or W1? And what can I do to resolve it?