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

Oscar-7 and the ITU

Jim Jerzycke, KQ6EA asked the question about Oscar-7:

> Aren't the Satellite Sub-Bands a "Gentleman's Agreement" like
> the FM vs SSB 'agreement'? I don't understand why I couldn't
> use the AO-7 70cm uplink frequency as long as my class of license
> allows me to transmit there. What am I missing here?
> 73, Jim  KQ6EA

The basic is answer is a qualified YES & NO. The reason for the yes/no
ambiguity is that there are two sets of issues involved.

                 Please -- DON'T SHOOT THE MESSENGER!


Internationally, all frequencies are allocated by the ITU (International
Telecommunications Union) at a WRC (World Radio Conference). Each nation
then ratifies these allocations as an international treaty. Because of its
unique status, and to keep us on a parallel with all the other services, the
ITU has chosen to define TWO separate relevant services: The AMATEUR RADIO
SERVICE and the AMATEUR SATELLITE SERVICE (I'll call these the ARS and ASS).

Allocations to the ARS are the ones relevant for 99% of all of amateur
radio. Some frequencies are set up on a regional basis (Europe + Africa are
Region 1, the Americas are Region 2, and Asia + Oceania are Region 3). As an
example 2 meters is 144-148 in R2 but is only 144-146 MHz in R1. The 144-146
band is uniform world-wide. In some areas, especially in the VHF-UHF
spectrum, some allocations are not even region-wide; the UK has a 70 MHz 4M
band, the US has the 222-225 MHz band.

When the ITU established the ASS in the 1970's, they allocated to amateur
satellites all the exclusive world-wide amateur bands, including 21-21.45,
28-29.7 and 144-146 MHz (no, neither 50 nor 222 MHz is on the list!). But
the 70 cm band is not EXCLUSIVE to amateur radio and, after much dickering
at WRCs in the '70s, the 435-438 MHz band was set aside for the ASS even
though it is shared (with radiolocation services).

When the 435-438 MHz ITU allocation was hatched, AMSAT was already pregnant
with AO-7 "in the basket" using 432.125-.175 MHz, and we were given a "wink
wink" "OK" along with a strong message "but don't ever do it again!". In
some countries (like the UK) there were even more stringent objections and
some countries never permitted to operate.

But you ask "The satellite only listens on 432.15. Why is all this ASS
allocation crap even relevant?". Unfortunately the ITU's ARS vs ASS
distinction applies to BOTH the satellite and the user on the ground.
Therefore when you have a QSO with another amateur on a tropo (or even EME),
you are operating the ARS. As soon as you point your antenna at a satellite,
you are operating in the ASS and are, in principle, subject to different
rules. [Don't yell at me -- I'm only the messenger!]


I started off by saying that the answer to your question was yes/no, so let
me explain that bipolar bit of thinking. After the ITU allocates a frequency
to the ASS or ARS, then the FCC can give you the right to use it. But the
FCC want Amateur Radio to be self-policing and they don't want to hear of
"turf battles". The FCC refuses to enter the fray on 10 vs 15 kHz frequency
assignments on 2M FM.

With self-policing in mind, amateur radio societies around the world
established the IARU (International Amateur Radio Union). One of the IARU's
functions is to attempt to establish band plans suitable for different
areas. Clearly the band plan need by amateurs in Alaska (thousands of km in
size, with a total population ~500,000) is very different from the
coordination needed in Europe where some countries are only a few hundred km
in size.

In the VHF/UHF range, most problems are pretty local. The main exceptions
are weak signal DX (meteors, tropo, EME etc) and Amateur Satellites. Both of
these have received unique slots in the international bandplans. On 2M,
although the satellites are legally permitted to use the entire 144-146
range, but the IARU bandplans show the 145.8 - 146.0 sub-bands.


Now back to Oscar-7. When you attempt to use this "Phoenix from the Ashes"
resource in Mode-A there is nothing to worry about. Both legally (in the ITU
context) and morally (in the IARU context), the use of the 2M -> 10
transponder is 100% "clean".

The Mode-B situation is a different matter. You are making use of the
antique AO-7 hardware and are not operating on a legal ITU frequency; and
the frequency is not listed in the IARU bandplans. Whether the FCC (in USA)
or Home Office (UK) or other national authorities will say "wink wink" and
ignore the "accident of history" transgression is uncertain. My gut feeling
is that it will not rise to visibility on their radar screens, and nothing
unpleasant will happen. In terms of "What to do?", I'm reluctant to see the
issue brought up to the FCC; there is a chance their answer would be NO!.
I'm adopting the attitude
    "'Tis far better to beg forgiveness rather than asking for permission".

73 de Tom, W3IWI

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