[Elecraft] help

[Michael Slater / BC]

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> Today's Topics:
> 
>    1. Re: KXAT1 with dipole (Karl Larsen)
>    2. RE: Does KX1 have CW spot? (Steven Pituch)
>    3. N2CQ QRP Contest Calendar: Aug 26 - Sep 25, 2006 (Ken Newman)
>    4. K2 CW Tuning Indicators (Roy Morris)
>    5. Re: K2 CW Tuning Indicators (Tom Hammond)
>    6. k2 #4930 completed (g0wfhchris)
>    7. Another K2 Mod (w6jd at comcast.net)
>    8. Re: Another K2 Mod (Bill NY9H)
>    9. TT Triton IV - How does it compare to the K2? (Darwin, Keith)
>   10. Re: Another K2 Mod (Phil Kane)
>   11. ALL BOATANCHORS ARE SPOKEN FOR (Ed - K9EW)
>   12. RE: KX1 Sidetone--N0MF's Technique (Mike Fitzgibbon)
>   13. Re: RE: KX1 Sidetone--N0MF's Technique (Leigh L Klotz, Jr.)
>   14. RE: RE: KX1 Sidetone--N0MF's Technique (Steven Pituch)
>   15. 2nd Generation Un-Module PCB Kits (Robert Johansen)
>   16. KX1 - Full power on internal battery (John Harper)
>   17. Re: KXAT1 with dipole (Dan Presley)
>   18. Re: KXAT1 with dipole (Karl Larsen)
>   19. RE: KXAT1 with dipole (Don Wilhelm)
>   20. Re: [QRP-L] Japan Ham Fair 2006 photos, (Martin Gillen)
>   21. RE: KXAT1 with dipole (Alan Biocca)
>   22. K2 price increase (Dr. Dan Swartling)
>   23. Re: KXAT1 with dipole (Dan Presley)
> 
> 
> ----------------------------------------------------------------------
> 
> Message: 1
> Date: Wed, 23 Aug 2006 05:54:20 -0600
> From: Karl Larsen <k5di at zianet.com>
> Subject: Re: [Elecraft] KXAT1 with dipole
> To: Dan Presley <dpresley1 at comcast.net>
> Cc: elecraft at mailman.qth.net
> Message-ID: <44EC41EC.4080001 at zianet.com>
> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
> 
>     Guys, my money is on the connector on the feedline. It must have a 
> short developed since the last time you used it. Or the short might be 
> at the antenna feed point.
> 
>     The feed line length is just not a factor even when there is RF on 
> the shield, and there is some.
> 
>     The MFJ Antenna Analyser will find the problem. I love mine.
> 
> 73 Karl K5DI
> 
> 
> 
> Dan Presley wrote:
>>> -------------------------------------------------------
>>>
>>> You should not have had any trouble with a center fed dipole, Dan. 
>>> The issue
>>> with the KX1 ATU, as with any ATU, is impedance extremes. Because of the
>>> limited number of inductors and capacitors that could be fitted into the
>>> tiny space available in the KX1, it has a more limited tuning range 
>>> than any
>>> of the other Elecraft tuners.
>>>
>>> The end of a dipole presents a very high impedance, possibly in the
>>> thousands of ohms. At the other extreme, a very short antenna will 
>>> present a
>>> very low impedance, often less than an ohm. Actually, end-fed short 
>>> antennas
>>> often tune up more easily because they are working against ground and
>>> typically Hams have lousy RF grounds <G>. Even with several "radials" 
>>> the
>>> ground impedance will likely be in the tens or, more likely, the 
>>> hundreds of
>>> ohms. That's in series with the antenna so what the tuner is matching 
>>> is a
>>> total impedance of perhaps a hundred ohms or more. The fraction of an 
>>> ohm
>>> that the antenna represents is just part of the total. It's also why 
>>> such
>>> antennas have a very, very low efficiency: often less than a few 
>>> percent.
>>>
>>> In your case, I'd suspect you had an unlucky length of feed line. 
>>> Unless the
>>> SWR is truly 1:1 on that feeder, something that is almost never 
>>> achieved in
>>> practice, the feed line acts like a random impedance transformer. I 
>>> suspect
>>> you got unlucky and the combination of the effect of surrounding 
>>> objects,
>>> antenna length, feeder impedance and feeder length all added up to an
>>> impedance the KX1 ATU couldn't handle. Adding a few feet of feed line 
>>> will
>>> usually fix that.
>>>
>>> Another possibility is a short or open, as you suggested.
>>>
>>> Ron AC7AC
>>>
>> Thanks,Ron and all of those who replied for the good advice. I'm 
>> betting you're right on the money as far as feedline length. I'll put 
>> the antenna back up and check it with my dipper to see how it reads, 
>> and also with the rig in 'cal' (tuner bypass) mode. That'll tell me 
>> also if there's a short somewhere too. I tend to forget about the 
>> feedline length as I often just use an endfed wire from the KX1, or at 
>> home I use ladder line. I know this can still happen with ladder line, 
>> but perhaps less of an issue than coax.Besides, the ol' Johnson 
>> matchbox is pretty forgiving:)
> 
> 
> 
> ------------------------------
> 
> Message: 2
> Date: Wed, 23 Aug 2006 07:23:52 -0500
> From: "Steven Pituch" <spituch at ev1.net>
> Subject: [Elecraft] RE: Does KX1 have CW spot?
> To: <elecraft at mailman.qth.net>
> Message-ID: <004b01c6c6ae$ff2cc0d0$6801a8c0 at TOSHIBALAPTOP>
> Content-Type: text/plain;	charset="windows-1250"
> 
>  Hi Alan and Don and all,
> 
> Yes, it is not really a problem not having a CW spot button on the KX1.  I
> am supposing that the narrow position of the filter is such that you
> probably can get within about 50 Hertz or so of the target.  I realize now
> that the rig can't send an audio tone simutaneously with being in receive
> mode.
> 
> I am not sure how the audio feedback works but I figured someone may have
> figured out how to activate a command and get audio feedback on the same
> frequency as the sidetone and use that to estimate proper pitch.  It was
> just a thought.
> 
> What I really need to do is borrow a KX1 and use it for awhile to get a feel
> for the rig.  I think I can swing that locally.
> 
> Thanks all for the input.
> 
> Steve, W2MY
>