[amsat-bb] Band designators, Modes

Paul Stoetzer n8hm at arrl.net
Wed Jul 6 17:52:13 UTC 2016

AMSAT publications generally use the "new designators" developed prior
to the launch of AO-40, though sometimes with a parenthetical
reference to the old mode designation.

For example, from the website post regarding the selection of
RadFxSat-2 (Fox-1E) for a CSLI launch:

"The Fox-1E spacecraft bus will be built on the Fox-1 series but will
feature a linear V/U (Mode J) transponder “upgrade” to replace the
standard FM repeater which Fox-1A through D have carried."

Several parts of the website (such as the frequency guide) also use a
less known custom with the second letter in lower case (to indicate
that the second letter is 'down').

Eventually I would hope we would move away from "five and dime" or
"nickel and dime" to using C/X in reference to 5 GHz uplinks and 10
GHz downlinks.

Regardless, I do think using letters to indicate uplink and downlink
is both meaningful and useful. I especially appreciate the history
behind the A, B, and J designations (A and B originating with AO-7's
two transponders and J originating with AO-8's JAMSAT built
transponder) and use those in general conversation with other
satellite ops since it's even easier than saying U/V or V/U. The
downside with U/V and V/U is it can get confused. For example, I know
that a well-known but poorly-informed purveyor of amateur satellite
information consistently confuses the two in his materials.


Paul, N8HM

On Wed, Jul 6, 2016 at 12:04 PM, Peter Laws <plaws0 at gmail.com> wrote:
> On Mon, Jul 4, 2016 at 2:59 PM, Peter Laws <plaws0 at gmail.com> wrote:
>> I thought AMSAT was moving away from Modes A, B, J, etc, but they seem
>> too entrenched and still appear in current pubs.
> I don't much care which designators are used but I would like to see
> AMSAT pick one and stick with it.  If the organization wants to move
> away from A/B/J/KT/whatever, and towards a combination of uplink and
> downlink band letters, great, but then it needs to be a complete
> break.
> Or simply conclude that no one could handle the new style and just go
> back to A/B/J/etc and come up with new single letters for the new
> combinations.
> Or are we *really* going to stick with "nickel and dime"?  Mode C/X
> sounds way better to me.
> All that said, I keep finding more stuff for my table.  I didn't
> really realize that the "hole" in our 13 cm S band was taken up mostly
> by the pay radio monopoly (who are on the ground as well as in the
> sky).  Lots of other services nipping at our heels, too.
> Putting new satellites on C/X is a good idea on many levels.
> --
> Peter Laws | N5UWY | plaws plaws net | Travel by Train!
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