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Re: Why V/S in stead of U/S



Don, w7das wrote:

> and I like the "quietness" of the 13cm band, aside from the 
> clicking from all the wireless access points surrounding me.  

Around here cordless phones and other Part 15 devices are part of that 
noise too...and more are added every day. But I agree, S-band downlink 
is wonderful, especially when there's enough power.

> ...and I don't have a purse to "lose" my radio in thank goodness  ;-)

When my HT is in my purse, it's not "lost"...even if it isn't hanging on 
my belt along with other nerdisms. I even sometimes work LEO FM 
satellites on it _when_I'm_operating_portable_, off an Arrow.

But it's *not* part of my fixed station, it's for portable operation. 
That's why it's small. That's why it's battery powered. That's why it's 
either in my purse (in the cellphone pocket) or on the charger.

My mobile UHF/VHF rig is "special purpose" too...while it has done one 
or two satellite contacts (including a rather memorable UO-14 QSO in 
motion one morning on the way to work) that's not its primary purpose. 
It's not properly part of my fixed station either, even though I'm sure 
with enough cables and switches it could be done. That radio is not 
"lost" either, it's where it belongs: either in the driveway or out on 
the road. It's just not in my shack.

I think to respond "Oh, well just duct-tape an HT to your desk for the 
uplink for this bird and add some adapters and another coax switch or 
two" very much misses the point.

I have an FT-847 for working sats on 2m (along with UHF and HF) on FM 
SSB or CW. It has a number of features specific to satellite work, and 
they're a great operating convenience. If you are just starting out on 
satellites, or you only work one bird, I suppose you can throw together 
any old collation of radios and cables that suit that one mode. You may 
not be ragchewing (who can do ragchewing on an FM LEO?) but you might be 
logging. Or adjusting freqencies. Or antenna tracking.

Tying up the VHF section that had been a perfectly good IF freq on 
previous S-band birds is a serious inconvenience to a goodly number of 
existing already-engineered ground stations that use surplus S-band 
downconverters and don't already have a pile of separate redundant 
transceivers available to accomodate the rechanneling of the uplink.

Now that the supply of surplus downconverters has dried up, I suppose 
it's not as much of an issue for new operators, they'll have to buy 
downconverters specifically made for whatever IF they want to run, or 
pay extra for a switchable one.

I'm not expert on the engineering issues on board the spacecraft that 
make it dangerous to operate it in the same S-band mode used by AO-40, 
but I do know what havok it creates here for me here on the ground, and 
I suspect I'm not alone. Obviously it's kind of late to do anything 
about it now; the bird's already on-orbit. But I think it's a decision 
that unfortunately limits the S-band audience of the satellite.

  73 de Maggie K3XS

-- 
-----/___.   _)Margaret Stephanie Leber CCP, SCJP/"The art of progress /
----/(, /|  /| http://voicenet.com/~maggie SCWCD/ is to preserve order/
---/   / | / |  _   _   _    `  _  AOPA 925383/ amid change and to  /
--/ ) /  |/  |_(_(_(_/_(_/__(__(/_      K3XS / preserve change amid/
-/ (_/   '        .-/ .-/        ARRL 39280 /order."-A.N.Whitehead/
/________________(_/_(_/_______AMSAT 32844_/<maggie@voicenet.com>/
----
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