home
***
CD-ROM
|
disk
|
FTP
|
other
***
search
/
Hackers Underworld 2: Forbidden Knowledge
/
Hackers Underworld 2: Forbidden Knowledge.iso
/
HAM
/
AORTEST.TXT
< prev
next >
Wrap
Text File
|
1990-09-17
|
23KB
|
450 lines
┌─────────────────────────────────────────┐
│ THE Authority On Radio AOR3000 SCANNER │
└─────────────────────────────────────────┘
By Nigel Ballard
28 Maxwell Road
Winton, Bournemouth
Dorset BH9 1DL
England
10 September 1990
I saw a question posed in the latest issue of Monitoring Times, Dear Bob
'what is the difference between a scanner and a scanning receiver?' Well
maybe that individual is better of with a less brain intensive hobby,
such as flower arranging.
A question however that seems rather pertinent when dealing with the
AOR3000 is, 'What is the difference between the 3000 and all the other
portable domestic scanners on the market?' Well in this article I hope
to address that question, and also give you an insight into the beast
itself.
A WOLF IN SHEEPS CLOTHING?
Yes it is rather, it has been said that you should never judge a book by
it's cover, and on first impressions, the 3000 does not look like very
good value for money. After all, the box looks cheap, mainly because it
is cheap, the front panel controls look like they were designed to be
used by a nimble fingered youngster, and overall the perceived value
seems much lower than the asking price, currently
UK 765.00 POUNDS STERLING
USA 995.00 US DOLLARS
HOW DO THEY GET AWAY WITH IT?
Well, from the outset, the original AOR2001 set the scanner world by
storm, it was not the box, not the price. No, the success was firmly
based upon two factors, superb coverage, and superb sensitivity. Up to
this time no one had produced a scanning radio that obviously had been
designed with these two factors firmly at the top of the shopping list.
BUT IS THIS WHAT I NEED IN A SCANNER?
Yes of course it is dummy! think of this, if your scanner cannot cover a
certain frequency band of interest, then you can't listen to it. And if
your scanner is as deaf as a post, then even if you are sat on a distant
but active frequency, then you wont be able to hear it either. All other
determining factors MUST be further down the list from these two.
ALL MODES, BUT ISN'T ALMOST EVERYONE ON NFM?
Give me a break fella. All normal international aircraft both civil and
military usually talk on AM for a start. And outside of the normal
118.00 to 136/8 MHz area you can find a whole mess of USAF aircraft
chatting on rather strange and discrete allocations. Outside of the USA,
many countries use AM all over the spectrum, the UK being a good example
as 80% of the countries police vehicles transmit ONLY on AM.
SSB, well admittedly a little more unusual to find interesting traffic.
I discount the heavy amateur use of SSB, mainly because as I am one I
can assure you that whatever mode you choose, you would be hard pushed
to find anything of interest going on. BLAH BLAH BLAH QSY QSL QRT
No thank you very much!
WFM, well you have the FM commercial radio stations, television and
radio broadcast links, and the USAF Airborne Command Post aircraft c/s
SILK PURSE,COMPASS CALL etc who just love WFM.
CW, well yes you have me on this one, I can think of no earthly reason
who you would want to scan or listen to CW. But better to have it than
not to. And you could be an old salty seadog radio operator keeping his
hand in on the traffic of the high seas 'AH, JIM LAD!'
ANY SCAN STEP BETWEEN 50Hz and 100KHz
Once again, wherever you are on the face of this planet, and what ever
radio system you are listening to, with this feature you will be able to
track their channel plan perfectly.
NO SET BANDS, BUT I LIKE SET BANDS ALL THE GOOD STUFF IS IN THEM, AND
IT MAKES THE RADIO EASIER TO OPERATE
Well in that case old son I humbly suggest you stick with your
UNIDEN/BEARCAT because the AOR3000 is an entirely different beast, thank
heavens.
I have owned scanners that have preprogrammed band limits that cannot
normally be expanded. God, how frustrating, I always wanted to know what
I was missing.
A WORLD CLASS RADIO FOR THE WORLD MARKET
So we should gather by now that the 3000 is NOT made for the USA market
or the JAPANESE market, but the world market. One radio covers the whole
spectrum from 100KHz straight through to 2036MHz no gaps and any mode or
channel step you care to use.
SENSITIVITY
Most banded scanners have their front end's tuned to each band centre,
the smaller the band, the greater the sensitivity they can achieve. Try
using the same front end technology on a radio that covers over 2GHz and
you end up with a receiver so deaf that if you were sat on the hood of
a police car in heavy radio conversation the receiver would still not be
fully quieted. AOR quite rightly were not keen on re-inventing the wheel
or for that matter trying to squeeze a quart out of a pint pot. They
opted for an altogether different approach, a high gain, very low noise
GaAsFET front-end protected by a bank of no less than 15 bandpass filters!
THE OLD BANDPASS APPROACH
Bandpass filtering is not a new approach by any means, many radio's use
them to block out traffic from adjacent bands. The 3000 has a whole bank
of them (an incredible 15) that are automatically switched in as required
as you scan around the spectrum. This approach allows for maximum gain
while maintaining good selectivity across it's entire range. There are a
great number of scanners currently on the market that boast impressive
coverage, a good example is the ICOM R-7000, what it makes up for in
coverage it most defiantly loses in sensitivity, just try switching in
the GHz button and see what you pick up over 1300MHz! Not a lot I think
you will find. The 3000 on the other hand has sensitivity figures that
hold up pretty good, right up to the 2000MHz area. And this is a first
for scanners. Remember, it's no good having the coverage if you can't
hear the traffic!
BYLINE #1
The usual trade-off for wide coverage without overload problems is to
have a front end that is not over sensitive, i.e. the TANDY 2004/5/6.
AOR seemed unhappy with having their scanner branded as a so-so
performer, therefore the 15 bandpass filters block most of the adjacent
strong traffic that usually stomp all over receivers with a HOT front
end.
DESIGN PHILOSOPHY
THE CASE
Now we have established where the AOR team were going, let's discuss
the towns they forgot to visit.
As in the 2001 and 2002, AOR still keep churning out models in the same
dreadful plastic case. I realise that designing a custom injection
moulding is expensive, but as AOR have sold thousands and thousands of
scanners using the same case, you would have thought the investment had
been recovered, and the introduction of the 3000 would have been a good
time to start afresh. But no, where the 2001 had one main circuit
board, the 2002 had two, and yes the 3000 has three. It's a pretty
tight fit, with the middle board completely sandwiched between the other
two. Repairing it would be a nightmare, but as the Japanese have a
knack of making things that work, I hope this will not be a problem.
GUESS MY WEIGHT!
As in all previous AOR press releases, the 3000 was rumoured then
publicly displayed almost two years before the general public got to buy
one. As mentioned by me in a previous article, AOR are keen on
publishing the birth weight even before the baby is born.
DELAYS
Firstly there were strong rumours that AOR had some technical
difficulties, not surprising when you consider what's crammed into that
tiny box. Then we heard a test batch kept losing their minds, or should
I say memories. And then when the first batch arrived, the public were
not at the top of the list. Well then who was?
MOD
Ministry Of Defence, the word 'MOD' is an umbrella term that happily
covers everyone from the armed forces to a whole gamete of covert
listening establishments, not least of which was GCHQ. This stands for
Government Communications HeadQuarters. GCHQ had near wet their pants at
the thought of the imminent arrival of these tasty li