[Elecraft] Elecraft Power Monitor for P3

[Dave Cole (NK7Z)]

Hello,

I have a new Elecraft P3 transmit power monitor, and it may have a 
problem...

After install I upgraded the firmware on the P3, etc.

When I transmit digital, sometimes it will show full power of 50 watts, 
with a SWR of 1.32:1, which matches my HF-AUTO, and my Ameritron AWM-30 
wattmeter.

The next time I transmit, it may show 20 watts, with a SWR of 1:1, while 
the Ameritron and the HF Auto show all normal at 50 watts, and 1.3ish:1. 
  The next time I transmit, it will show maybe 30 watts, and a 1:1, 
again, the Ameritron, and the HF-AUTO show 50 watts, and 1.3ish:1.

I thought it might just be signal changing due to  being digital, so I 
tried it on CW, same action, the P3 Transmit monitor is all over the 
place, and showing a 1:1 SWR when failed, but 1.34:1 when correct for power.

Next I thought it might be the on and off action from CW showing this... 
  I switched to AM, and with the K3 set at 100 watts, I see 25 watts 
out, and the same action on the P3, all over, while the other two watt 
meters and SWR meters are stable from transmit to transmit...

So thinking it still might be something in my cabling, I replaced all 
cables, and ran the output of the radio to the TX monitor, and the TX 
monitor to a Bird Watt meter, then the Bird to a dummy load...  Same 
thing, the Bird is rock stable, the P3 Transmit monitor seems to be all 
over.  The only thing consistent is that when I get a bad reading on the 
P3 Transmit monitor I am ALWAYS showing a 1:1 on the P3 Transmit monitor.

Just to be sure, I ran the transmit calibration on the K3, and that went 
perfectly well, and succeeded on all bands, at all power levels.  Same 
results with regards to teh P3 Power Level Monitor...

Any ideas?


73s and thanks,
Dave
NK7Z
http://www.nk7z.net