[Elecraft] KAT 500 Loses Match

[Ken WA8JXM]

It's possible that something is arcing and, of course changing the  tuning.

Do you have the internal tuner in the K4?  If so, does it behave the 
same way?

Why do you have the amplifier running?  30m is as restricted power band.

If you leave the amp and tuner out of the circuit and transmit with the 
K4 directly, does the SWR meter stay steady, or does it fluctuate at 
full power?

Ken WA8JXM

Why is the amplifier connected?  30m is a restricted powerband.

On 1/12/2024 4:46 PM, Paul Ecker wrote:
> I am experiencing a new problem for me, with my KAT 500. So far I've
> noticed this issue on 30M. I am using a dipole cut only for 30M with an SWR
> of 1.2 to 1.3 max SWR across the band. I “trained the tuner” at 20khz
> segments on 30M.
>
> Setup is K4D, KAT 500 & KPA 500. Win 10 pc.
>
> Running CW, I can start transmitting and all is fine- my LP100A is showing
> 1.2 SWR and am getting max power out of the radio. Then all of sudden the
> SWR jumps to >9.0. The KAT starts chattering and finds a new match. But if
> I start transmitting again – pwr out is only about 10 W at that new match,
> and eventually the tuner becomes untuned again. Sometimes, it will then
> hold the tune but still only getting abt 9-10w power out. The issue occurs
> with KPA500 both on and off.
>
> Does this sound like a KAT 500 problem or maybe an RFI problem.
>
>
> 73 Paul
>
> w2eck