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

[Don Wilhelm]

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
> >
>