[Elecraft] KAT500 tuning problem

[Don Wilhelm]

Bill,

After you do the initial TUNE (training the ATU), do you switch it to 
MAN?  If not try that and see if it corrects your situation.
If not, then it is time to contact support.

73,
Don W3FPR

On 2/4/2016 4:17 PM, Bill wrote:
> For the past month I have been experiencing tuning problems with the 
> KAT500.
>
> The antenna in question is a simple 75 meter dipole fed with coax. You 
> tune the antenna at 3922, 2955 and 3975 - just for example. When you 
> return to those frequencies, a few hours later, the tuning is all off 
> and the KPA500 demos its displeasure by beeping and flashing lights. 
> Retuning will again hold for a few hours, then all goes haywire again.
>
> I have given shake test to the antenna/halyards -  with an analog SWR 
> bridge in line - and see nothing to indicate breaks or damage. I 
> replaced the feed line and it still does everything the same. All coax 
> lines inside have also been changed out - to no avail.
>
> I should mention that this problem exists on an alternate antenna 
> also. The alternate is also a dipole type. No remote baluns, nothing 
> other than simple center insulators. Chances are they are built 
> properly - been doing it for over 55 years and have never experienced 
> anything like this.
>
> I have reset the KAT500 to default a couple of times - reinstalled the 
> software - all the things you do with black boxes - went through the 
> training thing. I spoken with Elecraft and followed their instructions 
> to the letter also (which were the same as what I had been doing). It 
> all holds well for a few hours, then goes wacko.
>