[Elecraft] Problem with 17m band in K2 + KAT100/KPA100 in EC2

[Marcin SQ2AF]

Don,

Today I have checked all connections in KPA100 T-R switch - they was OK.
After connection checking I assembled KPA100/KAT100 again and started
TX on 17 m again - the problem still occurred.
But .... as you know I'm digi modes fan so, all the TRX keying was
made by computer. Today, when I have been use VOX or foot switch the
problem disappeared!
In this moment I know, the problem occurs only when computer control K2 keying.
So, it clears why TUNE coming back RX to normal sensitivity.
Do you know what can I do now?

73,
Marcin SQ2AF

K2 #5408

2006/9/7, Don Wilhelm <w3fpr at earthlink.net>:
> Mike,
>
> I am certain Marcin will be interested in your results when portable.  The
> only thing that I can think of is a bad connection in the KPA100 T-R switch,
> but then I am just guessing.  Marcins's problem continues until the KPA100
> switches out at the 10 watt level, so your problem may be different.
>
> 73,
> Don W3FPR
>
>
> > -----Original Message-----
>
> > Don,
> >
> > I am experiencing the same or a very similar problem as Marcin.  It
> > only happens on 17M and only at high power.  That is why we do not
> > see it after a Tune operation.  If I turn the power down to 30W or
> > less, no problem.  It makes no difference whether the KPA100 is the
> > top cover or remoted in an EC2 with the KAT100.  I haven't determined
> > exactly how much power I have to be running before the problem
> > occurs.  I suspect RF getting somewhere it shouldn't but have not had
> > the time to track it down.  It does seem to be antenna dependent even
> > though I get a good match to the 102 foot doublet I use.  I will get
> > a chance to test my theory next week when I take the K2/100 portable
> > for a week using a different antenna than I do at home.  If it occurs
> > only at the home QTH then the problem is in the antenna system and
> > probably stray RF affecting something in the K2.
> >
> > 73,
> > Mike K2/100 #2221
> >
> > At 01:31 PM 9/6/2006, Don Wilhelm wrote:
> > >Marcin,
> > >
> > >There is nothing in the KPA100 or the base K2 that would cause
> > that problem
> > >on 17 meters only.
> > >In the base K2, the relay switching is shared for 17 and 15 meters except
> > >for relay K6 in the bandpass filter, and in the KPA100, all circuits are
> > >shared between 17 and 20 meters.  You would have a problem on either 20
> > >meters or 15 meters in addition to 17 meters if it was associated with
> > >either the K2 or KPA100 switching relays.
> > >
> > >If you have a dedicated 17 meter antenna, you may want to investigate the
> > >switching to that antenna.
> > >
> > >TUNE should behave the same as transmit, but you say that receive
> > >sensitivity does not drop after TUNE - that is indeed strange.
> > We need more
> > >data.
> > >
> > >73,
> > >Don W3FPR
> > >
> >
>
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