I suppose for the DX you are talking about, one wouldn't have to worry
much about lots of power, so, the rest involves "reasonable" noise figures
in the RX chain... not hard to do these days with quiet FET's getting
cheaper all the time. W6PQL found a really neat enhancement-mode FET that
he has been building preamps out of, and it looks useable thru at least
5760 Mhz possibly... Low cost 10 Ghz front ends are as near as your local
Satellite TV dish... The LNB's with a bit of work, well, work... and work
well!
The ones with two parallel amplifier chains would supply you with the RX
path amplifier chain AND the TX path amplifier as well... remember the DX
you are talking about can be worked with 10mW or less using that same
dish as your antenna! With a 1296 IF, the mixers are sitting there also!
The rest of the equation is still the clean, stable local oscillators...
That has always been the "big hangup" with building microwave gear, and,
really is the place to "spend the money"... If you have 432 as well as 2
meter IF gear (like an FT 817 lying about loose) then you have half the
battle solved, as with appropriate fundamental oscillator frequencies,
only TWO multiplier chains need be built, one for 2304 and 5760, the other
for 3456 and 10368, the oscillators running at 1872 Mhz and 1104 Mhz
respectively.
Unfortunately, not too many "off the shelf" solutions unless you shop
carefully for used gear.
W1GHZ has a document on his website that may interest you...
Eric
KB7DQH
> Are there any low cost options to get onto the bands above 1296? I.e.,
> cheaper than a DEMI transverter.
> I'm line of sight to a number of rover and multiop portable sites (Mt.
> Wachusett, Pack Monadnock, Mt. Greylock) and close to line of sight to
> others.
> I'm guessing that it wouldn't take much of a rig to work 6 or more
> stations in June and Sept on each band. The minimum usable would be
> something that would allow me to work 65 miles line of sight.
> CW only would probably be OK.
> Homebrew SDR solutions would be really neat.
> Any clever ideas out there?
> --Walter, K1CMF
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