[Elecraft] Using K3 for 2m EME

[Lance Collister, W7GJ]

I wonder if anybody has any ideas about this.  Prior to my trip to TX5K, I used my K3 
for receive on 2m EME by setting up the transverter port for a 28 to 144 MHz 
transverter, and I just plugged my 28 MHz converter into that nicely isolated receive 
port.   The receiver worked great, but I was eventually interested in getting the 
internal 2m transmitter module so I could use the more stable K3 on XMIT too.   I was 
using my old IC746 as a separate transmitter on 2m EME, and - as most of you know - 
it drifts quite noticeably every sequence.  And besides, I thought for traveling it 
would be convenient to have both 2m and 6m capability in one lightweight box.

So, now I have the 2m module installed in my K3 ;-)  The problem is that I can no 
longer use the transverter port....it is hard wired to the 2m module.   And 
apparently, the only 2m connector is the new one (a BNC called antenna jack #3) that 
is used for box receive and transmit.   So there seems to be no way to use the K3 
with a separate protected receive line anymore!

For 6m EME, there is no problem - I just bring my 6m preamp line into the separate RX 
ANT jack, and the 6m transmit power goes out through the UHF antenna jack #2.   For 
2m EME, though, I can't figure out how to bring in a separate receive line (either on 
2m from my tower mounted preamp or after my receive converter at 28 MHz) and still be 
able to transmit on 2m.  The K3 does not support cross band operation, so I cannot 
use the RX ANT jack to safely receive my converter output on 28 MHz and still 
transmit using the internal 10w 2m module.

Has anybody figured out a way to modify the circuitry or software to provide a 
separate receive line for 2m operation?  It seems like I just made a very expensive 
mistake, and should have just bought an external transverter so I could retain use of 
the separate transverter receive jack on the rear of the K3.   If not, I guess I will 
just have to go back to using the IC746 for my transmitter on 2m, and defining a 
second transverter setting for the K3 that will allow me to bring in my 28 MHz 
converter output into that receive only jack.  This latter option DOES seem to work, 
but of course, the internal transmit capability of the K3 on 2m is thrown out the window.

Of course, there is always the solution of adding more sequenced external coaxial 
relays to switch the K3's solitary new BNC antenna jack #3, between my driver amp 
input and my 2m preamp output. However, the whole point of this expensive exercise 
was to try to take advantage of the great separate receiver antenna capabilities 
offered by the K3 on all other bands, apparently EXCEPT if you add the built-in 2m 
option :-(

Any suggestions would be greatly appreciated.    Elecraft Tech Support suggested that 
I ask users for ideas, since they also are baffled on how to make this work, and I 
guess are surprised at my application.   MNI TNX and VY 73, Lance

-- 
Lance Collister, W7GJ
(ex WA3GPL, WA1JXN, WA1JXN/C6A, ZF2OC/ZF8, E51SIX, 3D2LR, 5W0GJ, E6M)
P.O. Box 73
Frenchtown, MT   59834-0073
USA
TEL: (406) 626-5728
QTH: DN27ub
URL: http://www.bigskyspaces.com/w7gj
Windows Messenger: W7GJ at hotmail.com
Skype: lanceW7GJ
2m DXCC #11/6m DXCC #815

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