[Elecraft] KX1 Keying problem

[Sean Cavanaugh]

Hi Don,

Thanks for the tips. It turned out to be a bad 1/8 in plug. The 
insulation between tip and first ring is too small, so it doesn't fit 
correctly. I probably tugged just a wee bit on the cord while testing 
(apparently repeatedly... go figure).  If I don't insert the plug in all 
the way it works fine. If I use the KXPD1, it works fine.

I'll just change the plug and hit the air with my KX1 and my straight 
key. Thanks and 73,

Sean - VA5LF

On 25/02/2010 3:12 PM, Don Wilhelm wrote:
> Sean,
>
> You say the KXPD1 has been working fine, so try a test. Put the KXPD1
> back on, but leave the KX1 set for INP HND.
> Use the dot side of the paddle only and 'key' it as you would with a
> hand key. Does the KX1 do the same thing?
> If it behaves OK, then look carefully at your hand key(s) and their
> cabling. I would expect the resistance when the key is open to be very
> high, but if you find it is down in the thousands of ohms, that may
> cause the behavior you are seeing - clean the dust off the key (top and
> bottom) and see if that helps
>
> If it mis-behaves with the KXPD1 during the test above, then the problem
> is in the KX1 - look at the soldering for the key jack, C32 and C33, R16
> and R17, U1 pins 24 and 25 and RP1 pins 5 and 6 - reflow the soldering
> for these components with a hot (750 deg F) iron and see if that helps.
> Also be certain the U1 microprocessor chip is fully seated in its socket
> - the leads should be in the socket almost up to the shoulders. It takes
> some amount of pressure to seat it - place both thumbs on the chip with
> the fingers beneath the board and apply pressure. Many 'strange
> happenings' are cured by fully seating the microprocessor chip.
>
> If all that fails to resolve the problem, about the only thing left is
> some strange behavior in the microprocessor itself, but this is the
> first time I have heard a report like yours, so that is very far down on
> the suspect list.
>
> 73,
> Don W3FPR
>
> Sean Cavanaugh wrote:
>> Hi all,
>>
>> I have a KX1 that has worked just fine for me for the last 2 years or
>> so. I've been using the KXPD1 paddles without problem.
>>
>> I wanted to try working on some QRP contacts for the SKCC, so I
>> plugged in my straight key and set the input to "hnd". When I start
>> sending, the rig keys normally for about 20-30 seconds, then stays
>> keyed for a random amount of time, whether the key is closed or not.
>> It will usually stay keyed for between 10 and15 seconds, then unkey.
>> If I close the key again it will do the same.
>>
>> I can get it to stop by unplugging the key or waiting, but it will
>> continue to have this unkeying issue until I turn off the rig. It will
>> then work for 20-30 seconds and start all over again.
>>
>> I've tried a different key with the same result.
>>
>> Any ideas? I'd love to not have to use the big rig for SKCC contacts.
>>
>> Thanks and 73,
>>
>> Sean - VA5LF
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