[Date Prev][Date Next][Thread Prev][Thread Next] - [Date Index][Thread Index][Author Index]

Re: 1.2ghz uplink

>From: "John Stephensen, KD6OZH" <kd6ozh@gte.net>
>AMSAT has said in the past that both 70 cm and 23 cm uplinks would be
>supported with a 13 cm downlink on some schedule to be worked out after
>commissioning. However, all discussions of the 3 cm downlink have assumed a
>23 cm uplink.

John, I have not seen this discussion about the 3 cm downlink, but it would
not surprize me.  I do note in Amsat publications addressing the mix of
modes to be used on AO-40, that they expect that 6 cm, 3cm, and 1.4 cm were
to be modes used mostly by microwave experimenters and not the main
satellite operator.  Therefore, they may reason that such people would
already participate in mode-LS in most cases.  However, if the 70cm analog
uplink is usable, I would expect to see mode-UX supported somewhat.

>----- Original Message -----
>From: "hasan schiers" <schiers@netins.net>
>To: <amsat-bb@AMSAT.Org>; "Edward R. Cole" <al7eb@ptialaska.net>
>Sent: Friday, 02 February 2001 15:15 UTC
>Subject: Re: [amsat-bb] 1.2ghz uplink
>> I've been following these discussions and trying to see what kind of setup
>> is going to be required. In theory, I had hoped that we could make the most
>> use of existing equipment for one half of what may still be functional on
>> the bird.
>> Uplink: 70cm
>> Downlink: 2.4 gig (or whatever it is close to that), with 144 IF.
>> This way, we can use our existing 70cm radios/amps/antennas and only haveto
>> buy a downconverter and antenna.
>> Why invest in 1.2 ghz uplink gear if 70cm will work?
>> Is there something wrong with my plan?

Hassan, the use of mode-US is certainly a natural one for the mainstay
mode-UV satellite operator, considering most would have commericial
satellite radios operable on 2m and 70cm.  In that regard there is nothing
wrong with this approach.  Of course we still need to find out if 70cm
uplink will be usable.  At this point I have little expectation that 2m
will be used at all.

As far as your question why invest in 1.2 GHz, it is looking like this may
become, by the demise of the 2m and 70cm xmtrs, the prime mode for AO-40.
Two meters is rapidly deteriorating as a usable band in some parts of the
world, and 70cm is not allocated in others.  Clearly, Amsat is promoting
mode LS.  In the end its your decision.  

Finally, I was not excluding other modes.  I was merely replying to Bob's
request [below] for info on getting on 23 cm.  BTW these are just my
observations and predictions.  I have no influence with the command group.

73, Ed
50-144-432-1.2G-2.4G-10.4G...and maybe 24G

>> > >From: "Bob V. Johnson" <w7lrd@juno.com>
>> > >Hello
>> > >The many threads and ideas on s-band reception have been an education
>> > >me, and I  hope to have s-band receive capabilty soon.  Receiving
>> > >telemetry is ok but I would prefer listening to K0BLT' melodeous voice
>> > >drifting down from above.  Or Jerry/oe or Paul/vas,  or anyone else I
>> > >enjoy  talking to.  I want to start a thread on what is required to put
>> > >1.2ghz signal 'up there', no politics, guns, cuss words, someones
>> > >or lack thereof.  I want to learn the requirements needed, as in;
>> > >transverters, antennas, link budgets, etc etc.  I am  working on my
>> > >microwave-phobia, and this bb is a fantastic resource.
>> > >73...Bob...W7LRD

Via the amsat-bb mailing list at AMSAT.ORG courtesy of AMSAT-NA.
To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org