Re: K3 reduced or no TX output on low and high bands


Not sure with those two bands if it could be the dreaded lpa board failure. 

Mike R

Absolutely Awesome 

On Apr 16, 2020, at 8:59 AM, Jarmo Blomster <jarmoblo@...> wrote:

I sent this to K3 support, while waiting their answer I ask here also.

Serial is 0691.
Last week I noticed that my K3 has no TX output on 6m band.
I run Transmitter gain adjustment procedure on all bands.
I noticed that 160m and 10-6m has problems and can not finish properly the adjustment procedure.
Here are my results using a dummy load:
Transmitter Gain adjustment
Measures RX: 14.9V, 1.19A, PA 24C, FP 20C
Band, Reaching Power, SWR,   Voltage, Current, Error
160m,             2W, 1.2-1, 14.7V,    2.78A, ERR TXG
 80m,             5W, 1.0-1, 14.6V,    3.27A
 60m,             5W, 1.0-1, 14.6V,    3.33A
 40m,             5W, 1.1-1, 14.6V,    3.30A
 30m,             5W, 1.0-1, 14.6V,    3.38A
 20m,             5W, 1.0-1, 14.6V,    3.19A
 17m,             5W, 1.0-1, 14.6V,    3.19A
 15m,             5W, 1.0-1, 14.6V,    3.25A
 12m,             5W, 1.0-1, 14.6V,    3.24A
 10m,             5W, 1.0-1, 14.6V,    3.35A, ERR TXG
  6m,           0.1W, --,    14.8V,    2.19A.

For the measurements I replaced the KAT with the antenna interface card, so the problem is not in KAT.
I guess that possible components that can cause such problems are LPA and maybe the SWR Bridge.
What components in the LPA or in SWR bridge can cause such?
Has anybody had similar problems?

73 de Jarmo, OH8KVA

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