Katahdin Mountain APRS Station

for the Appalachian Golden Packet Event

Bob Bruninga, WB4APR@amsat.org, Annapolis, MD

This is one of the 15 hill-top sites from Georgia to Maine we hope to visit this summer on 26 July for 6 hours to attempt to relay a text message using hand-held radios the 2000 mile length of the Appalachain trail. This is to be a no impact Leave-No-Trace type of event of a few individuals at each site. . See the Golden Packet plan. . Other hikers equipped with APRS ham radios are welcome to participate with advance notice.

Katahdin Mountain is the northern end of the Appalachian Trail. It is a very rustic mountain only accessible by foot and the last 100 miles of the AT leading up to it are a vast wilderness. It resides in Baxter State Park where every effort is made to keep the rustic wilderness intact and undisturbed as much as possible. Car access can get to Abol Campground at 1300 feet and only 3.8 miles to the peak, but at 1000' rise per mile. But sacrificing the 4000' of additional elevation may complicate the link to the KQ1L-6 Maine-Relay site.

ALTITUDE:. . . . . . . . . . . . 5267 feet (or 1300' for easier access)

POSITION: . . . . . . . . . . . . 45-54.3N / 68-55.3W (Peak)
. . . . . . . . . . . . . . . . . . . . . . .45-52.43N / 68-57.82W Abol Campground 1300'
. . . . . . . . . . . . . . . . . . . . . . .45-51.60N / 68-53.13W Eastern Site 1300'

LINK SOUTHWEST:. . . . Maine-Relay KQ1L-6

TEAM LEADER:. . . . . . . KA1YBS Tim D'Apice [tim . dapice * gmail . com] for 2010!
. . . . . . . . . . . . . . . . . . . . . . Mark Ford KB1MSA, Bethel, Maine Volunteered to climb Old Spec Mountain to operate.

COMMENTS: .

Timothy D'Apice KA1YBS has volunteered to climb Mt Katahdin next year (2010). He rushed to the AT in 2009 to participate as a hiker on Long Trail/Appalachian trail Junction, Bald Mountain, Bennington VT. He exchanged packets with Mount Greylock which was the only operational station within range during this event.

Of course, it is possible to minimize the exertion by finding a readily available site which has decent altitude but not require the full 4500' climb. One possibility is a drive-up to the Abol campground, but the direct shot to KQ1L-6 Maine-Relay digi runs into a small pair of hills about 1/3rd of the way. Hiking the first 1.2 miles from the campground to gain 500' is relatively benign to get to a 1800 or 1900 foot operating point, but this actually makes the blockage by one hill even worse. Another possibilty is to move a few miles to the east nearer the Visitors center and park at the road (900') and then an easy 1 mile hike to 1300'. Being further to the east gets the RF path around the two hills of concern. Please see the three ray traces below:

The challenge is the mountains inbetween KQ1L-6 and the lower more accessible sites we have selected on Katahdin as shown in the KX4O analysis below. But with knife-edge refraction and maybe a small beam, the signals should be workable. From the top, I bet a direct shot to Mount Washington might work?


DETAIL LINK ANALYSIS BY KX4O: Be sure to follow the two RF links at the top of this page to see the excellent and very detailed RF link analysis performed for every link in this project by KX4O John Huggins. Each RF link shows the terrain map elevations, the AT trail in yellow, the RF path loss itself including fresnel zones and finally a statistical plot of the probabilities of link availability. We will very much be looking at the results of this project compared to the pre-event analysis and predictions. Here are the links:

LINK SOUTHEAST: . . . KQ1L-6 to Mt Katahdin RF Link Analysis

All of KX4O's links are shown on his AT Links Page.

You can see the locations of these sites on the Baxter State Park map. Now, back in the campground. If a test can show this site is useable, maybe a short 20' mast and good beam strategically located to cut through the least number of trees might make the link.

.

The campground should be pleasant during the event and Leanto's shown above are avaiailable on a reservation basis. Whoever is going to do this trip should get their reservations in early for the 26 July event. A good location for the beam antenna might be nestled at the northeastern end of a short road in the campground so that it can shoot back unobstructed for a hundred yards or so to the southweast and hopefull clear as many trees as possible beyond that as shown in the blue arrow in the image below.


The ground falls away in that direction, so tree absorbtion should be minimial if the mast is high enough... This is an opinon based on no fact whatsover, other than google earth and photos. Sacrificing almost 4000 feet of elevation will make this link questionable, so it will have to be checked out well in advance. The intermediate relay point between Mount Washington and this site has been moved much closer to Katahdin to make up for this loss of height.

But using the campground and making this a drive-up station should make it easier to find a volunteer team. Of course a hiker could hike to the top with an APRS HT and be able to really seal the deal by digipeting through the campground station. My guess is that the beam for the campground should be 6 elements or more to get the maximum gain possible.

AUDIO NOISE PROHIBITED in the park: N1ARU, Cory Golob [cory.m.golob*gmail.com] reports that Baxter State Park is very serious at preserving the natural beauty of the environment and that includes noise. Originally, the rules for Baxter State Park prohibited any kind of radio, cell phone or other sound making device according to rule 25 of Baxter State Park:

25. AUDIO DEVICES: Audio devices such as radios, televisions, cassette players, or cellular telephones may not be operated within the Park. (see rules).

Fortuntely in the Spring of 2009, the new rules have been modified to more truely meet their original intent, and that is to avoid any nuisances or disturbances to other park visitors... SO as long as we use headphones, we are OK.

Bob, WB4APR

See my other GENERAL page on APRS applications and Ideas on the AT


Return to the APRS HOMEPAGE or SiteMap.