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Re: AO40 user population



Message text written by Tony Langdon
>
I can only speak for myself, and in my case, it's purely money.  However,
the same argument applies, to a large extent for V/U, so it's not
aprcifically a microwave issue (in fact, I still consider 2.4 GHz to be a
much more practical option than V/U, due to antenna requirements).<
----------------

        Yup, old money is always a problem. But, I respectfully submit,
there are ways around it: FWIW, here's some food for thought: If you work
me work on any VHF/UHF band, chances are I will be using a pair of late
1960's Drake R4B/T4XB as the IF section. Vacuum tubes. Disable the screen
voltage on the T4XB finals so it can't transmit, tap off the driver tube
plate circuit with a small cap and it makes a fine 10mW 10M exciter. Those
drive homebrew transverters, consisting mostly of MMIC's and $3 balanced
mixer modules. Sometimes several transverters in a row; i.e. 10M to 2M or
70cm, then that to whatever. Background hiss can be pretty strong (I built
a W9GR version 2 filter to save my ears. Got it dirt cheap since it was
long obsolete. Highly recommended). My audio isn't the best (as one clown
has seen fit to tell me in detail), my L-band transmit converter used to do
some mean FM'ing (I fixed it), I don't have Doppler correction or
coordinated frequency pairs (which would probably confuse me anyway) or
computer controlled tracking. I run separate transmit and receive feed
lines so I can't transmit into my preamps when I push the wrong switch.
With this many switches, that's not an uncommon occurrence. I use cable TV
surplus (trashed by the cable company) 3/4" hardline. My "modern" radio is
a Kenwood TS-430S, about 15 years old. It's got a transverter port and
works great. An Alliance U110 cheapy antenna rotor served as my elevation
rotor for 12 years, until a couple of months ago.  I drilled a hole in the
bottom so the water  would run out and wouldn't stand inside of it. May it
rest in peace. The elevation indicator sender was a pot with big nut hung
from an arm on the shaft, with a plastic food container over it. Replaced
it every 2-3 years. Gets you in the ballpark, then you swing to peak. Every
antenna from 2M through 5760 (except a Transystem; one of 3 S-band
antennas) is homebrew. Computers? Your 1600 Athlon is King Kong compared to
anything I have ever had. An old 133 Compac handles all manner of digital
comms (including unattended WXSAT) and an 800 Athlon built from TigerDirect
mail order parts (incredibly cheap) does the rest.
        The point here is simply that they are many ways to do things. I
have no formal training in electronics (mechanical engineer), but it
interests me deeply. I find homebrew to be wonderfully rewarding. Sure, I
have a whole closet full of things that didn't work. But a lot of them did.
And I learned something from every one of them.
        Pardon my rambling. Have fun... and drive on!

73,
Ed K9EK
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