[amsat-bb] IRB's and Satellites.

[John Hackett]

OBSERVATIONS FROM NORWAY.   26-04-2007.

INTERNET REMOTE BASE STATIONS FOR SATELLITES.

Love 'em or hate 'em ... IRB'as are a part of amateur radio.

So ... why would LA2QAA want to use one?. Well, they can! be used for 
operating satellites.

On a recent (unsheduled) visit to the local horse-spittle ... (I don't like 
these places, they're always full of sick! people) ... the surgeons 
positively refused !! to allow me to set up the satellite array in the 
intensive care unit while they performed renovation work on the pig's heart 
in LA2QAA's chest ... (oink!).

(PAPPA INDIA GOLF as in smoked bacon, not two legged creature with badge).

Their excuse was that the rotor noise might disturb the other patients 
snoring ... so lying connected to various hospital type spectrum analysers 
and other pieces of apparatus has a tendency to put a serious crimp in 
satellite operating for a while and it initiated the reasoning behind why 
LA2QAA might want to use an IRB, to get round the issue of being denied 
aerial privilages.

The following is a short article destined for the Observations from Norway 
pages on <http://observations.biz>

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AMATEUR SATELLITES AND IRB's

(IRB station = Internet Remote Base station).

FOR PEOPLE WISHING TO OPERATE AMATEUR SATELLITES BUT DON'T HAVE THE 
EQUIPMENT OR KNOW-HOW.

(The know-how can be found elsewhere on this website).

Visitors to the <http://www.observations.biz/> web page will soon become 
aware that LA2QAA & GM1SXX are always trying to help newcomers to amateur 
satellite operating by providing hints and tips in their satellite related 
articles.

Two of the main excuses used by potential newcomers for *NOT* operating on 
satellites are ...

1) The sophisticated equipment that is necessary is too expensive ...

and ...

2) I don't have the possibility of erecting rotatable beams ...

The facts are, neither of the above arguments are valid because ...

1) You don't *NEED* sophisticated equipment ...

and ...

2) Rotatable beams are *NOT* necessary to work satellites that are in low 
earth orbit (LEO).

While it is true that AMSAT (The Amateur Satellite Corporation) prefer to 
promote satellites with "cutting edge" technology that require expensive 
equipment, there ARE satellites that only require relatively simple 
equipment ... a flying FM repeater like AO-51 and analogue  ... (CW/SSB) ... 
satellites like AO-7 and VO-52.

Even if you don't have the necessary equipment at home to use any of these 
satellites, providing you have access to the Internet with at least a 300bps 
modem (preferably faster) you *CAN* work these satellites using only your 
computer!!.

Unlike Echolink, which is a 100% Internet based system, an IRB (Internet 
Remote Base) station transmits and receives via the ionosphere just like any 
"normal" amateur radio and aerial system. You only connect via the Internet 
to the remote base station ... the IRB transmits and receives your signal to 
and from the satellite via the ionosphere.

You can control all aspects of the remote rig directly from your computer 
keyboard or even use a 3G mobile phone. (LA2QAA has actually done it like 
this using Remote Desktop for Mobile phones software).

With the VK3UR IRB you can even turn the 70cm aerial remotely as well as 
choosing an appropriate power level setting, different modes, filters, 
adjust AF and RF gain etc just as if you were actually sitting in front of 
the rig. The VK3UR IRB uses a TS2000 transceiver so there are a lot of 
options.

Before reading further, it would be advisable to read "HOW MUCH POWER IS 
ENOUGH", part 1 on ...

<http://www.observations.biz>

HOW TO OPERATE THE VK3UR REMOTE BASE STATION FOR AO-7.

First ... read the instructions !!! and familiarise yourself with the rig's 
controls for changing frequency and the use of filters, operating modes and 
rotor control etc.

Next, tune the TX to 432.150 Mhz LSB, press "S" on your keyboard, this will 
put the radio into SPLIT mode, then tune the RX to 145.941 Mhz USB ... make 
sure you have a suitable tracking program on your desktop that calculates 
the azimuth and elevation as well as the necessary doppler offset. (LA2QAA 
uses NOVA). Now you can remotely turn the 70cm yagi towards AO-7 and operate 
just as if you were operating from your own shack.

REMEMBER !!! ... set up your tracking software QTH as Victoria, Australia 
... *NOT* your home QTH ... otherwise the passes will be (literally) half a 
world !! off.

Also remember ... to stay legal, you have to identify at least every 10 
minutes so you operate with the callsign VK3/YOUR CALL ... it is advisable 
to mention you're operating via the VK3UR IRB in Victoria, Australia so that 
the Ozzies don't think you're a pirate playing Silly Sods.

The coordinates for VK3UR are ... 37 degrees, 33 minutes, 43 seconds SOUTH 
and 143 degrees,
49 minutes, 7 seconds EAST in Victoria, Australia. (Enter these coordinate 
into your tracking program).

At the time of writing (24-04-07) the IRB is not set up for FULL duplex 
operation but you should have no trouble at all working ANALOGUE LEO 
satellites like AO-7 or VO-52 using this method.
The station is already set up for FM use with automatic doppler tracking and 
tuning for AO-51 or
The ISS ... (see the SETUP menu "special settings", satellite operations).

As well as having the radio interface on my desktop I have NOVA + the 
doppler corrections visible.
Of course, this won't be FULL duplex operation but you won't have any 
problem at all working ANALOGUE satellites with this set-up.

As with all satellite operating ... get into the habit of using those rather 
wierd things stuck to the side of your head ... (he means EARS, folks). 
LISTEN before you speak. Where appropriate, listen to the beacon BEFORE 
transmitting and "guesstimate" your power accordingly ... (now you know why 
FULL duplex is recommended for operating via satellite).

Actually, the MONITOR facility "could" be used if the IRB software was 
"tweaked" slightly.

You can obtain a password for operating the VK3UR IRB by sending the owner a 
copy of your current licence ... (providing it's a reciprocal licence with 
VK) ... to <dave at daves-portal.com>

The service requires no registration or donation fee.

Have fun!.

73 LA2QAA John.   <la2qaa at amsat.org>
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One very useful feature is that an IRB in a location remote from your normal 
operating position allows you to perform propagation comparisons.

Another is ... (in my particular case) ... soon after I lose AO-7 on certain 
passes at Frei Island, Norway ... (home QTH) ... I can pick it up again from 
Reston, Virginia ... (IRB).

The main advantage next to the aerial restriction issue is that an IRB 
allows those amateurs whom don't have the necessary equipment to try their 
hand at satellite operation, therefore, hopefully, bringing in some new 
recruits.

73 John.   <la2qaa at amsat.org>