[Elecraft] KX3 atu anomalies - or it is me.

[luca de marinis]

On Sep 18, 2012, at 10:00 PM, Matt Maguire <vk2acl at gmail.com> wrote:

> 
> On 19/09/2012, at 2:47 PM, luca de marinis <surfshot at gmail.com> wrote:
> 
>>> If you have initiated a tuning cycle with the KXAT3, and subsequently hold the XMIT/TUNE button, and the radio reports a VSWR of 1.4, then this means that the KXAT3 has not matched the impedance of the antenna system. This would be the case, for example, is the KXAT3 was set in bypass mode.
>> It is not on bypass mode.
> 
> Just check one more thing: in order to initiate a tuning cycle, you need to push the "ATU TUNE" button, not hold the XMIT/TUNE button. If the tuning cycle is successful, you should see an indication "1.0-1" come up on the screen. Is this what you saw?
Yes I tuned pushing ATU TUNE and not holding the XMIT/TUNE. After I tuned and read 1.0-1 I saw the VSWR graph on the KX3 indicating that there was still SWR so I held TUNE to see what the reading was.
> 
>>> If the SWR graph in your KX3 is set to read VSWR, and the KXAT3 has matched the antenna ad reported a VSWR of 1.0, and you see the SWR graph jumping around during transmit, then this could indicate flashover in the KXAT3. Normally this should only happen if the antenna system is very far away from 50 ohms. This is not likely to be the case here, if you indeed measured the VSWR of the antenna system independently with the MFJ antenna analyser, and found it only to be 1.4:1.  
>> 
>> This seems to be the case. So is it normal or not? Any idea how to fix it?
> 
> No, this is not normal. If you are quite sure that you have followed the suggestions given here and the directions in the owner's manual, then the next step would be to get in touch with Elecraft customer support, who can lead you through some more detailed troubleshooting.
> 
I will test again tomorrow and try on a dummy load and see if I see something weird. After that I will contact Elecraft as suggested.

Thank you
Luca
> 73, Matt VK2ACL.