[Elecraft] KX3-2M module?

[Edward R Cole]

Frequency drift +/- 10-Hz at 144-MHz may be fine for running 
digital-mode eme.  I typically think of keeping drift <20-Hz as a 
requirement.  It will depend on how rapid the frequency changes and 
how big the steps.  JT65 is fairly adaptable to some drift.

When I am in the "heat" of an eme contest with 5-7 stations calling 
me simultaneously on or near the same frequency (within 100-Hz) I 
select 20-Hz DSP bw to exclude another station capturing the decoder.

I have worked stations that have drifted 30 to 50-Hz through the 
course of a contact by merely reseting the center frequency to follow 
the change at discreet times.  If drift is faster than 50-seconds 
then it becomes a problem since one does not want a frequency change 
during a given sequence period (Nom. 1-minute).

I have discussed a few "fixes" off list with David Anderson if it 
turns out one is needed.
**This is only important to the eme'r or mw operator so will not 
affect the majority of users.**

On mw the frequency stability of the IF radio (KX3) is added to the 
stability of the transverter since they mix signals.  Many use PLL's 
for the mw transverter; for example on 10-GHz the frequency is held 
to 9x the synth frequency and resulting error is probably not more 
than 9-Hz and more likely half that.  +/- 19-Hz frequency uncertainty 
on mw is actually very good.

Might be a problem for mw eme'rs  so the KX3 might not be the radio 
to use.  EME Dxpeditions commonly do not operate above 2.3 GHz (LOx2) 
so the requirements are not as tough.  Far more common is 50, 144, 
432, and 1296 MHz eme dxpeditions (which makes KX3 very handy due to 
size...same issues as with portable IOTA, SOTA type operations).

So we will find out when I have one to test!

73, Ed - KL7UW
--------------------------------------------

From: Wayne Burdick <n6kr at elecraft.com>
To: gil at keskydee.com
Cc: elecraft at mailman.qth.net
Subject: Re: [Elecraft] KX3-2M module?
Message-ID: <27179E45-2ED7-4CDF-A066-02052409D2CB at elecraft.com>
Content-Type: text/plain; charset=us-ascii

When the extended temperature compensation is performed, short-term 
stability on 2 meters is about +/- 10 Hz, more than adequate for 
FM/AM/CW/SSB and some data modes.

73,
Wayne
N6KR


73, Ed - KL7UW
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