September, 2010

Eastern Utah & Western Colorado
Automated Packet Reporting System (APRS)

UI View Maps Here

Recommended Path Settings:
These comply with the national standard and should work most anywhere you travel.

Mobile/Portable Stations: WIDE1-1,WIDE2-1     This will work in most areas, and should always get you into the internet in Colorado. (In most of our area WIDE1-1,WIDE2-1 will usually get you into at least 2 Igates) Usually if you are not being seen, it's because you are out of range of any digipeaters or your packet is lost due to a collision, not because your path is too short. For some remote areas in the west (Central Nevada, Montana, etc.) it is acceptable to use WIDE1-1,WIDE2-2. You should never use a path that will exceed 3 digis! Near Metropolitan areas (like the front range) never exceed 2 digis and usually a single digi is adequate. The details of why this is important is explained below

For Fixed Stations:   (Homes, WX stations, etc.)   WIDE2-1       This will send your packet out via one digi in each direction that you can be heard. Since our digis are all on high locations you're likely to be seen for at least 50 miles. If you need a wider distribution for some reason, use a directed path (i.e.: GRAND,LKOUT,VAILMT)

Effective October 1st, 2005 - support for RELAY and plain WIDE was dropped from most of the Western Colorado Digipeaters.
It has already been dropped in much of the country including Arizona and New Mexico.

Timing:   You should never beacon more than once per minute. Once every two minutes is usually adequate. How often is someone going to look at your location? Normally if you're travelling on a highway they can presume where you will be in 30 seconds or a minute.
Limit your smart beaconing. Corner pegging is great but only up to a point. When travelling up or down a curvy road you can generate an excessive number of packets.
Keep in mind that if your packet takes 1 second to be sent, and you are running a two digi path (WIDE1-1,WIDE2-1), that it will take 3 seconds or more for you beacon to propogate through the area. If everyone is sending once per minute then there is only room for 20 units before the channel is completely saturated. If you beacon more often, less users can access the frequency.

Western Colorado & Eastern Utah APRS System

Mark Young - KC0RIA & Chuck Kimball N0NHJ have built quite a bit of the central western slope APRS infrastructure.
Digipeaters are located at:
Anvil Points (ANVIL) northwest of Rifle.
Aspen Highlands Ski Area near Aspen.
Bald Mesa (BALD) east of Moab, Utah
Baxter Pass (BAXTER) north of Loma
Blue Mountain (BLUEMT) east of Vernal.
Buffalo Boy Mine near Silverton.
Cedar Mountain (CEDAR) near Craig.
Chair Mountain near Marble / McClure Pass.
Grand Mesa (GRAND) east of Grand Junction
Green Mountain (GREEN) southeast of Delta
Hayden Mountain (HAYDN) a solar powered site near Red Mountain Pass south of Ouray.
Hill 71 south of Lake City.
Independence Pass near Aspen.
Kendall Mountain near Silverton.
Last Dollar Mountain (DOLLAR) near Telluride.
Lookout Mountain (LKOUT) near Glenwood Springs
Methodist Mountain near Salida.
Sunlight Peak (SUNLGT) SW of Glenwood Springs
Tenderfoot Mountain (TENDER) south of Gunnison
Uncompahgre Butte (UBUTTE) west of Delta
Waterdog Peak (WATRDG) southeast of Montrose
Wolf Creek Pass near South Fork.

Special Thanks to Harley (K5CHM) for all the efforts (lots of hikes to 13,010') to keep the Kendall Digi on the air.


Internet Gatesways are located in
Downtown Glenwood Springs
On Flattop Mountain above Montrose
on Raspberry Ridge west of Montrose at 10,000'


In addition Eagle County Ham Operators (ECHO) supported the building of the Vail Mountain - Far East (VAILMT) digi.
Gary Hanson assisted in the building of the Salt Creek (SALTCR) WIDE1-1 digi east of Collbran.


Keri (KB0YNA) & Chuck have installed an Igate in Meeker. Keri also operates the I-Gate in Grand Junction.
Keri is also helping to get a digi constructioned near Crested Butte (CBUTTE)
Royce (K7QEQ) donates the space for the digipeater on Bald Mesa near Moab, and internet for the
Abajo Peak Igate near Monticello, Utah. John Ball (N0GIO) donated the space and solar power for digipeater on Parrott Peak NE of Cortez.

In addition Dave Herman KD0H operates a Digi on Mt Werner and an Igate near Steamboat Springs.

Mt. Werner (WERNER)
Thunderhead IGate (KD0H-11)

Mark Cheavens KC5EVE also operates a digi on Missionary Ridge and an Igate near Durango.

Missionary Ridge Digi  (DURNGO) NE of Durango.
Igate (KC5EVE-14) north of Durango.

Stephen Sanderson W7FXH operates an Igate

Igate (W7FXH) South of Pagosa Springs.

Barry Bradley WB7REL has several digis throughout Utah, including the Cedar Mountain (CEDRMT) Digi near Green River, UT, and has a digi under construction for Bruin Point (BRUIN) near Price, UT.

I've likely missed someone in eastern Utah and Western Colorado. But take the time to Thank your local Digi & Igate operators.


View from the Glenwood Springs IGate - as heard on RF



WHY short paths?
Every time your packet is digipeated it reduces the available space for other packets. If you are near Grand Junction, and your packet is using WIDE1-1,WIDE2-1 (The recommended path for mobiles) it's likely to be heard for 200 or more miles in most directions. -Example: You hit GRAND with WIDE1-1, CEDMT then hears your packet from GRAND and digis the WIDE2-1. Also ANVIL hears the packet from GRAND and digis, LKOUT hears the packet from GRAND and digis, ABAJO hears the packet from GRAND and digis, etc. If you also hit BAXTER it will digi on the WIDE1-1, and BALD will digi from BAXTER on the WIDE2-1, etc. The new system helps to eliminate the duplication that use to occur so that a single digi shouldn't repeat your packet if it heard it before. As you can see you've covered a lot of ground, and that was with only 2 digi hops. If you use 3 it gets even worse.

It's important that everyone keep the path as short as possible. Because if another station just sent out their position, and then you beacon, your transceiver will wait until it thinks things are quiet. But the GRAND Digi is still hearing all those other stations repeat the previous packet. That means your signal is competing with those other fixed stations. Who ever has the stronger signal might win, or neither packet may be decoded by GRAND. The less packets bouncing around the better your chances of being heard are.

For most users they want to be seen on the internet, and in the local area. Sending your packet across several states accomplishes little, and causes interference for the local users in those areas.

If you want to know even more detail on why the paths need to be short and how the current recommendations evolved see http://aprs.org/fix14439.html

Fixed Maps for Use with UI-View     Unzip these in your maps folder, and on ui-view under maps click on 'refresh map list'
Colorado - approximately 300 maps and inf files   ~22MB     Utah - approximately 26 maps and inf files   ~2MB
Arizona - approximately 26 maps and inf files   ~2.5MB     New Mexico - approximately 10 maps and inf files   ~.6MB

Questions? - Need help with your APRS setup feel free to contact Chuck Kimball     n0nhj @ amsat. org

Back to Chuck's Homepage

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