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"W4XE Repeater Group"
I run the local
Huntsville AICN node. Here is some information on what AICN is.
AICN
Alabama Inter-City Network
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The Alabama
Inter-City Network (AICN) is a linked system of Repeaters and Remote
Bases in Alabama that allow Amateur radio operators to converse over
long distances via 2 meters and 440 MHz. For example, a station in
Southern Alabama can directly talk with one into Northern Alabama.
Coverage also extends into East Mississippi and Southern Tennessee. This
system is on line 24 hours a day and requires no special codes to turn
it on. See the FAQ below for information on how to access a node in your
local area. AICN welcomes new users and also new potential local node
sites.
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Huntsville, AL W4XE AICN SITE
Port 1: GE Mastr II VHF Repeater (Mobile Conversion)
Port 2: Motorola Micor UHF Mobile remote base
Port 3: GE Phoenix SX UHF Mobile remote base
RC-210 Repeater Controller (new!!)
The system provides local Huntsville with VHF Repeater
service. It can tie into the AICN statewide network via UHF link to
Tuscallosa, AL. It can also tie into the MTEARS Tennessee UHF Linked
repeater system. Thus this system acts as a hub repeater between the Alabama
and Tennesse networks.
Current AICN Network
CITY |
FREQ |
PL |
CWID |
Arab |
145.55 simplex |
203.5 |
- |
Atmore |
Potential site |
- |
- |
Birmingham |
145.57 simplex |
203.5 |
B |
Greenville |
145.19- |
203.5 |
- |
Greenville 440 hub |
N/A |
N/A |
- |
Huntsville |
145.23- |
186.2 |
- |
Mobile |
Down |
- |
- |
Montgomery |
444.450+ |
203.5 Aicn
100.0 Local |
Muscle Shoals |
145.41- |
203.5 |
- |
Thorsby |
145.43- |
203.5 |
- |
Tuscaloosa Tall Tower 440
hub |
N/A |
N/A |
- |
Configuration on 3/26/2005
The following is a list of the MTEARS Tennesse UHF Linked System:
To find out more about MTEARS Emergency linked system go to:
http://www.mtsh.org/mtears.html
Alabama Inter-City Network (AICN) FAQ
- Frequently Asked Questions
Who are some of the
hams behind AICN?
We
gratefully acknowledge Dave/KX4I Tuscaloosa North Hub "Tall Tower guy,"
Jack/K4YVV (Muscle Shoals site), the guys down south who keep on
rebuilding the southern area, including Bob/W4MPQ (new chief design
orchestrator, Greenville), Stuart/WD4JRB, Wiely/KE4LTT & Reuben/AD4R
(all of Montgomery), Bobby/N4AU (Wetumpka), Jack/KS4UN (Dadeville),
Ralph/W4XE (Huntsville) and untold others. |
What has been
happening to AICN?
You
probably didn't know, but the whole state has been reconfigured and is
in reconstruction, based on different site equipment and linking thrust
by all of us that have carried it on. We had an older system in the mid
90's. We are in at least the 3rd generation now, with some
previous veterans having moved to other things, some of which happened
based on main link-site attrition and loss (including tower
lease/contract changes as years went by and other changes) which
incurred loss of equipment and convenience to old sites. It's a long
story, so we're into rebuild mode now. |
What is the AICN?
The Alabama
Inter-City Network is a linked system of Remote Bases in Alabama and SE
Mississippi that allow users to converse over long distances via 2
meters. For example, a station in Ellisville, MS can talk with one in
Opelika, AL., or someone in Mobile could talk with someone in Florence.
This system is on line 24 hours a day and requires no special codes to
turn it on. |
How Do I access the
system?
First you need to
determine your local frequency (see separate listing for the frequencies
used). You will notice that the sites are on standard, coordinated,
repeater pairs, with the standard +/- 600 KHz offset. That means that
you can treat a site as you would a normal repeater, with a few
exceptions that we'll cover shortly. Once you've set your frequency and
offset, you will need to program your radio's sub audible tone encoder.
This might be new to you, since most repeaters do not require this tone
to operate. Most current 2M radios have this feature, but it seems like
they all activate it a little differently, so consult your user's
manual. Just remember that it's really just a two-step process... Select
the desired tone frequency and then turn on the encoder. My FT-5100 uses
the FN + TONE buttons and the main dial to select the tone and the TONE
button to turn the encoder on or off. Deciding which tone to use is
easy. Most Alabama sites use 203.5 Hz and all Mississippi sites use
136.5 Hz (check the listing above). Now that you have your RF and tone
frequencies set, you're ready to go. |
What is the purpose of requiring this tone? Is the AICN a closed system?
Congratulations; you
can now be considered an advanced user of your radio, especially if you
programmed this into a memory channel! No, the AICN is not a closed
system. The reason the tone is used is to keep out the intermod and
other noise present at so many tower sites these days. Such noise at one
site would be rebroadcast over the whole system, tying it up. The AICN
sites are half duplex, meaning that although split frequencies are used,
a site can only transmit or receive at one time. |
Is that why I
sometimes hear only one side of a conversation?
Yes. When you hear a
one sided QSO, it's possible that the side you don't hear is on the same
site that you are. This is one of the differences between AICN sites and
standard repeaters. Signals received at a site are not repeated out of
that same site, but only out on all of the other sites. This was done
for several reasons, not the least of which is system cost (no duplexer
or special full duplex radio). Another reason is that the system is
intended for wide area coverage. Users are encouraged to use local
repeaters or simplex to chat when they are close enough to do so. If
they are not, then the AICN is there to use. If you wish to hear a local
user to you, one trick is to use the radio's reverse button to monitor
the input frequency. Another possibility is to try hearing another site. |
I've heard that this
system is for weather emergencies only, yet the other day I heard a
QSO concerning
fishing. Is this allowed?
Yes. The original and
most important reason for the system is to provide wide area
communications support for the Mobile office of the National Weather
Service (and others as well). The system has been used to both report wx
conditions and to verify conditions shown on their new Doppler radar.
While this type of traffic takes priority over all others, there is
another purpose for the system and this is to have fun. Use the AICN to
make new friends, keep in touch while traveling, or to visit old friends
who have moved. Using the system helps ensure that everything is working
and also allows users (potential weather spotters) to exercise their
skill at both using their own equipment and the system's. |
Why do people
sometimes ask me to repeat the first part of my transmission?
Due to the way the
UHF links work, there is some delay from when you first key your mic to
the time the last 2M-site keys-up. This is especially true when you are
conversing across the whole system. Let's use a worse case example. Say
that you are in Phoenix City and make a call to a station that is on the
Hattiesburg, MS site. First, you key your radio, which keys the UHF
radio at the Phoenix City site. Phoenix City keys the Clayton hub
repeater which keys the Dozier relay which keys the Mexia Hub which keys
the Isney relay which keys the Ellisville Hub which keys the Hattiesburg
2M transmitter. That's eight transmitters and eight receivers (including
the two user’s) that have to come up in a chain reaction on every
transmission that takes a second or two to happen. What it boils down to
is that you need to pause a moment after keying before speaking, or your
first word will be missed. |
I hear a lot of CW on
the system. What's that all about?
Besides the regular
ID for the system, several of the older sites have a single letter ID
tagged on to the tail of any transmission from that site. This helps
isolate trouble spots as well as give a general area where a station is
located. I've included a list with the site listing. |
Can I use the UHF
backbone for communications?
It is recommended
that you don't, as it is preferred to limit access to the backbone for
linked sites only. It is frustrating to have the whole system tied up
with a one sided QSO because a station is going backwards into a site to
carry on what is really a local QSO. Monitoring the UHF output from a
site, however, might give you a way to hear local stations using your
local site assuming you are in the patter of the UHF link antenna. |
My dual band mobile
rig has a cross band repeat function.
Can I use it to link
the local site here to another frequency for use around my home?
Yes, but please use
caution. Be sure that the squelch will not open on noise, intermod, or
such. Use CTCSS to prevent this. Another potential source of
embarrassment is with your rig's scan. What if the rig was inadvertently
placed in scan or on the wrong channel? Police calls have no place on
the ham bands! It's even worse if your rig has been "MARS/CAP" modified
and AICN traffic goes out on non-amateur frequencies. Don't laugh, it's
been known to happen. |
What can I do to
help?
Use the system! 99.9%
of the traffic on the system has been carried out in a courteous manner.
We ask that you help by continuing in this manner. The system is not
intended to be for any one person or group, so greet newcomer and
old-timer alike... Friendliness and consideration will ensure an
enjoyable, effective system for all. As with any amateur communications,
allow time between transmissions for other stations to enter the QSO.
Remember that this system takes a second or so to come up, so allow at
least that amount of time for others. Another way to help is by
supporting any effort by your club in sponsoring part of this system.
Hope to hear you soon! |
Click below for some maps and photos
AICN COVERAGE MAP (subject to change)
:
A view from the AICN 'Tall Tower'
Use BACK key to return
Links to Alabama Repeater Related Sites:
North Alabama
Repeater Association
http://www.qsl.net/nara/
Huntsville Amateur
Radio Club
http://www.harc.net/
Alabama Repeater
Council
http://jschool.troyst.edu/~arc/
Birmingham Club
http://w4cue.com/
W4VM Repeater
http://www.qsl.net/w4vm/
W4XE Repeater
http://www.qsl.net/w4xe/
Skywarn
http://www.nalsw.net/
Madison Co. ARES
http://www.harc.net/documents/ares.htm
Material Acknowledgements to: KE4CAP, Editor Alabama Section News;
KE4OLR, Brian and WD4EGF, Don
AICN Webmaster: Ralph W4XE send email comments to: [email protected]
[email protected]
W4XE
ã 2002
Home | 443.625 | 444.300 | 145.23 AICN | Vital Statistics | 53.21
This site was last updated
01/02/07
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