Temple Mountain 447.425 UHF Repeater

WA1ZYX / KA1QFA/KB1QPC

WQKQ332

447.425Mhz 141.3PL

Temple Mountain

Sometime during the spring of 2005, conversations began about the possibility of putting this repeater on Beech Hill in Dublin, NH. A repeater was built up, and installed at the same site as the Keene 443.8 machine for a few months for testing. After all, it's been about 12 years since I've set up a UHF repeater.

Repeater sitting idle on the test bench in my basement.

Receiving a signal

Transmitter on.... Turned down to an incredible 20 watts!!

The repeater, consisting of two GE Phoenix-SX's, a CAT200 controller and a set of Motorola duplexers worked quite well, but the radios were programmed with the repeater in a channel position other than channel one. This was fine, as long as there were no power failures at the site. If one occurred though, the radios wouldn't have come up on the repeater channel.... So... I popped out the chips, and got them reprogrammed so the default repeater channel would be on one.

Now by the time I was actually ready to install the system on Beech, all kinds of legal problems and assorted other issues had developed between the current owners of the repeater site and the town of Dublin, it was determined that it wouldn't be worth the hassle not to mention how or when or if they'd be resolved.

I had a few other potential thoughts and was fortunate enough to have the Summit of Temple Mountain offered up. The site was only populated by a single tower with a couple cell systems on it and a single VHF system. No other radio equipment at all!

I modified the frequency coordination and was able to get that approved for the new location without any problems, although I did raise the eyebrows of the 440 coordinator when I forgot to convert the site elevation from meters to feet. I believe the conversation began something like this... "what are you trying to pull? Summit of Temple Mountain - 572 feet? I don't think so...." So after a few chuckles, we got that straightened out and life was good.

So, now the day before the repeater was installed on Temple, Dale - N1NCI, calls me on the phone and asks, "What are you doing tomorrow"? And the rest is now history. That was Jan 6, 2006.

The Repeater Equipment

The Repeater Equipment consists of a pair of General Electric Phoenix-SX's interfaced to a CAT200 controller. The radios then go into a set of Motorola BpBr base station duplexers through a little under a hundred feet of 1/2 inch Andrews Heliax to a tower top mounted Celwave PD-201 Stationmaster fiberglass antenna. The transmitter is currently set for 20 watts to allow the mobile unit performing the transmitter function to run continuous duty without catching fire.

The day of the repeater installation began relatively uneventfully. I had put all the stuff in a pile that we would need for the trip the night before. Tied the heliax onto the roof of my truck, got out my heavy winter clothes and whatever else I thought we might need. Dale and I had planned to meet at his shop around 8:30am and leave from there.

Back of Dales service truck with all the "stuff"

I get to the shop, transfer stuff from my truck into his and we head out to the Keene West Fire Station to pick up the ATV (6-wheeler) to use to get to the summit. We get the trailer hooked onto the pickup, tow it out of the station and start the ATV, just to make sure it's going to run okay. No problem. Fires right up, plenty of gas and good to go!

We arrive at the parking lot and get ready to back the ATV off the trailer and find out that the throttle cable is frozen solid! (It's only in the lower 20's right now) We fiddle with that for a while, but no luck. Thinking that we're not really going to get up there today - so close - I say to Dale, "Got any string"? And so, I became the ultimate "back-seat driver"..... Dale would nod, and I'd tug on the string. Not the smoothest operation, but it worked, and we continued on...

Summit of Temple Mtn as seen from the parking lot with the camera zoomed in all the way.

Finally made it to the top!

And you all thought I was kidding about the string...

And there it is, the top of the tower prior to mounting the repeater antenna.

I was absolutely amazed at the view from this site. It was a little hazy on the horizon, but we could easily make out the Boston skyline. I never thought it was this great. We walked around a bit and I took a few pictures, but I forgot to get some from the top of the tower. Have to wait until Spring for those I guess. Seems like not being able to get onto Beech Hill was actually a blessing in disguise!

Looking across the valley at Pack Monadnock

Looking toward Concord, NH

Looking toward Manchester. The right hump in that mountain in the center is Mt Uncanoonuc and we could see the towers just fine.

Looking toward Boston.

A much better picture looking toward Boston. Look in the center of this image, now follow the furthest ridge you can see to the right, toward the trees. See that little mound just to the left of that white patch? That's Boston...

Okay, back to the project.... Dale scrambled up the tower to mount the antenna and hang the feedline while I installed the actual repeater and performed ground crew duties.

Dale - N1NCI, already has the mounts on

Taking the antenna off the tow line

Tightening it up

There it is, all ready for the feedline to be connected. Power hasn't even been turned on yet.

Joel - WA1ZYX installing the heliax connector.

Now the power is on! Officially "On-The-Air"

The antenna

And finally back at the parking lot with the ATV back on the trailer and ready to head back to Keene.

On Sept, 16 2007 we (Dale and I) trekked up there again because it had been determined that there was an antenna problem. We had been noticing a decline in coverage, and the antenna analyzer confirmed that.

The first step after scrambling up the tower was to terminate the feedline with a dummy load. As soon as the pig-tail to heliax connection was opened up, our worse fear.... drip, drip, drip...... At least we knew for sure what the problem was. Fortunately, we had planned for the worse case and brought new feedline as well as a new antenna. Looks like we're going to basically replace everything beyond the duplexers.