Hello Bill.
10 Jan 98 14:01, Bill Dobiesz wrote to All:
 BD> I know others have done it before...but I would like to know if anyone
 BD> there has modified an 11 meter rig (specifically a Johnson Messenger
 BD> 123A) to 10 meter use.
I modified a 23 channel Cobra w/SSB to 10 meters, many years ago (c1979).
It was a lot of fun.
 BD> I have just inherited this rig, brand new, in the box, never used...I
 BD> have little use for 11 meters, much less a 23 channel radio...but I
 BD> *could* put a 10 meter radio to use.  I completely understand that it
 BD> wouldn't be as good as a REAL 10 meter radio, but I would like to get
 BD> my feet wet.
 BD>
 BD> Does anyone know, definatively, the practicality / legality of doing
 BD> such a mod, as well as how to do it?
If that's a synthesized 23 channels, it's a piece of cake.  Find/order four 
crystals, R&R them with the existing crystals, re-align the frontend and 
re-tune the tx for max output and your on 10m...
You'll need to know the mixer formula for the synthesizer before you can 
figure out the frequency of the 4 crystals I mentioned above.  On each 
channel, one of those 4 (say 10MHz oscillator) is mixed with 1 of 6 crystals 
(say 17MHz oscillator) to add up to the frequency desired, ñ the IF (usually 
.455Hz, sometimes 10.7MHz) frequency.
It's a very practical mod if you're inclined to use QRP on 10meters. 3watts 
isn't much, but the sun spots cycle is getting better. Hams are allowed to 
modify almost anything for use in the ham bands...the operative words there 
being, almost anything...
... Roy's Radiator Shop, Best place in town to take a leak...
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