[Elecraft] K3 false SWR indication with SSB

[Fred Townsend]

Mark I have not seen your problem so I tend to discount your explanation. It sounds like something is breaking down. Perhaps bad coax, antenna, insulator, or lightning arrestor. You could test with a TDR (Time Domain Reflectometer) or Hipot tester. If you lack the equipment connect a dummy load to the K3 and test. If that passes your problem is not in the K3.
73
Fred, AE6QL

-----Original Message-----
>From: Mark N2QT via Elecraft <elecraft at mailman.qth.net>
>Sent: Aug 19, 2014 12:15 PM
>To: "elecraft at mailman.qth.net" <elecraft at mailman.qth.net>
>Subject: [Elecraft] K3 false SWR indication with SSB
>
>My k3 flashes a higher swr indication with ssb voice peaks than with a steady carrier.
>
>If using an antenna with 1:1 SWR the bar graph flashes the first segment.  If swr is 1.5:1
>all the segments illuminate on voice peaks, as if swr was greater than 3:1.  To reduce the 
>uncertainty introduced by my antennas,  I connected a 50 ohm load after an external tuner 
>so I could create the 1.5:1 SWR, and got the same results.
>
>I assume this is a benign problem and likely caused by the non simultaneous sampling
>of FWD and REV power by the CPU.  
>
>However, if no one else sees this I'll do some more checking.
>
>FW 4.81/2.83 and TX Gain Cal done recently.  
>
>Mark. N2QT