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Bandplanst-bb] previously ao-40, now AO-40 Band Plan



 "Edward R. Cole" writes:

> Since you raise the issue of a band-plan for AO-40 {not a bad idea}, and at
> the risk of raising a flame-throwing issue, I wonder if psk-31 and SSTV
> should be considered now, too.  We have, at this early point in AO-40
> operation, the chance to establish some standards...hopefuly that will ward
> off problems later.

Amsat-UK's beginners book says:
(begin quote from a long time ago)

As with other amateur allocations, a band plan already exists for the 
orderly use of the space sections of the amateur bands and this is shown 
below for analogue transponders on present and future satellites. This 
plan will apply to all amateur spacecraft at all times, except when special 
trans-satellite tests are being conducted.

           ----------------Downlink Passband----------------
                  CW              Mixed            SSB             
        LF                         Mode                           HF
            5%    30%              30%             30%      5%                
Note:   (1)       (2)              (3)             (2)          (1)

Notes: 1) Guard  areas  to  avoid  interference  to  beacons. These 
          frequencies are available for emergency and bulletin stations.
       2) Rtty  and  sstv  are placed at the edge of the  cw  and  ssb 
          passbands;  conforming  to their use at hf where rtty is  present 
          within the cw space and sstv is transmitted in the ssb sub-band.
       3) Mixed mode area. This is recommended for crystal  controlled 
          stations, dxpeditions, or those wishing to work both cw and ssb.

This bandplan, first proposed by G3IOR (Amsat-UK) and G3ZCZ (Amsat-NA), has 
been adopted by AMSAT groups world-wide as the recommended operational 
usage of the AMSAT OSCAR communication transponders. The Russian Committee 
for Radio Sport have signified their agreement also. This conforms to the 
normal downlink usage of the satellites. The plan allocates a percentage 
of the available spectrum, as seen on the downlink, to different modes of 
communication. The relative amount of spectrum for each mode is thus the 
same for any analogue transponder in any satellite, whether inverting or not. 

(end quote)

Obviously, in the early days, no-one envisaged beacons in the middle of
the passband but, apart from that, the plan makes sense and, as on hf,
most people would probably go along with it (theres always the odd rebel 
though).

I'm throwing this out as an example of Robin's "open planning"; lets see
if some consensus can be achieved about how to manage the "beacon in the
middle" problem. 

My suggestion, which feels a bit clumsy because I haven't thought about it
in depth, is to have two clear-cut "virtual" passbands: one lf of the MB 
for cw and one hf of the MB for ssb. Modes which are not cw or ssb could
take an appropriate position to the usage on the hf bands ... so data 
(I'm talking about PSK, amtor, fsk packet or what have you, not stuff
that would properly go in the formal digital passband) would take a slice
at the top of the cw block. Sstv etc could take a slice at the low end of 
the ssb block. It may even be more appropriate to put the sstv at the top 
of the lower block (its so big its never likely to be full of cw stations).

Over to you guys. No need to copy responses to me personally; I'll get
them from the -bb. Open Plan: will it work ? go ahead and prove it.

73
Richard W L Limebear G3RWL
g3rwl@amsat.org
FOC # 1188

          So many beautiful girls ..... (sob) so little time
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