[Elecraft] KAT3 and Six Meters ...

[Jim Sheldon]

Rich and Joe,
I HAVE noticed the same problem on other bands as well.  Specifically, 160 meters, 15 meters and 10 meters as well as now on 6.  I don't notice it all the time on 6 and I thought it stoped when I put the ferrites on the antenna cables, but it cropped up again this morning on 6.  Later it reared it's head on 15.  

I have not noticed it on any of the other bands, but it may be related to a particular segment of the band 
and I may not have actually transmitted or run the tuner on that segment yet.  

My antennas are resonant on the bands they are used for with the exception of the inverted L which is resonant about 1850 on 160 and used with the tuner for the lower end of 160 and on 80.  

The problem does not seem to occur on 80 and on any other band but 160 with the L.  The ATU will find a 1:1 match on all bands using the L and doesn't exhibit the tuning anomaly on anything but 160 with that antenna.

That said, a second (sometimes it takes 3) touch of the ATU Tune button usually causes it to tune for a much longer period of time but it tends to find a match closer to 1:0.   This is particularly annoying in a contest on 160.   On 6, the 3 element yagi is resonant at 50.100 and I normally don't use the tuner, but I started experimenting with it after this problem was reported and I discovered that my K3 exhibits the same anomaly that Rich and Joe reported.

Jim Sheldon - W0EB
> Joe,
> You are not alone.  I've noticed the same problem here with my K3's
> ATU. With
> the ATU in BYPASS the SWR is low on my 6M yagi. When I turn the ATU
> on and press
> the tune button, the K3 finds a dip, but when I transmit, the SWR
> is much higher
> than with the ATU turned on. Pressing the tune button a 2nd or 3rd
> time makes do
> difference.
>
> As you reported, this does not happen on any of the other HF bands.
>
> 73,
> Rich - K1HTV
>
> = = =
>
> ----Original Message-----
> From: Joe Subich, W4TV [mailto:lists at subich.com]
> Sent: Friday, May 27, 2011 11:42 AM
> To: Elecraft Reflector
> Subject: [Elecraft] KAT3 and Six Meters ...
>
>
> I'm seeing a strange behavior with the KAT3 on six.
>
> If I engage the tuner it finds a low SWR and stops tuning.
> However, if I then close the Key the K3 shows "HI SWR" and folds
> back.  This
> happens even on the dummy load (1.15:1).
> It does not happen on any other band.
>
> Suggestions?
>
> 73,
>
> ... Joe, W4TV