Keene 6 Meter Repeater Installation

53.73 Mhz     141.3 Pl

Update: For the most current pictures and to jump right to the good stuff... go directly to the bottom of this page...

On July 9, 2000, Dale - N1NCI and Doug - K1ZO, climbed up the tower to do the initial antenna work to get ready for the new 6 meter repeater that is planned for the area.  While they were installing the receive antenna, up around 300 feet, Doug thought he may as well take a couple pictures.

The antenna was moved over to the new tower when the new tower was constructed, during the summer of 2003.  During the construction, the 1/2 heliax that used to feed the antenna was replaced with 1 5/8 heliax, so I doubt there will be much signal loss.  This is going to be a split site system and the EKW end will be the receive site.  The transmitter will be on another mountain a couple miles away.

November 8, 2003 I finally aligned the receiver for the repeater.  With the help of Dale, N1NCI and his service monitor, we were able to get the receiver going.  And it's going to play quite well too, I might add.  The transmitter gave us a slight problem, in that when we gave it a smoke test, we got smoke.  Not much, but enough for us to realize we had a problem.  Back to the drawing board on that for a bit.  I did some research and discovered that I had a missing jumper.  Installed that, and the transmitter fired right up worked just fine - maybe that was a bad choice of words after the "smoke" test...

So now I need to finish building up both ends and get them on the mountain tops, hopefully before snow.... Ooops, Nov 11, 2003 - too late.  

Update:  On Monday, Nov 24, 2003 there were a couple projects relating to the repeater going on.  Early in the day, Dale - N1NCI, installed the transmitter and link antennas on Hyland Hill, while Joel - WA1ZYX worked to finalize the receiver and link transmitter.  The receiver was completed and installed at the TV52 tower.  Currently, while in "test" mode, the link transmitter is running lo power and the 443.8 machine's remote base is listening to it, so you can talk in on 6m and out on UHF.  This will give me an idea of how well it hears.  The audio levels still need to be set up, so currently, it doesn't sound as good as it's going to, and it's operating in carrier squelch only.  Soon to be PL 141.3.  The tone decoder is installed, but I want to make sure that it works fine in carrier mode first, no other interference or stations using that freq.

Finally:  On Saturday, Sept 4, 2004, 53.73 officially went on the air.  Not bad, only 4 years since I first began this project.  Initial tests are going well.  I also still need to make a couple minor adjustments, but it's on the air and playing just fine.  Coverage seems to be pretty good too.

Here's a run down on the equipment...

The receiver is a single channel Motorola fire alert monitor interfaced to an S-Com 5K controller.  The link transmitter is an old Kenwood TH31BT 220 portable which is connected to a Cushcraft 220 yagi pointing across the valley toward Hyland Hill.

On the Transmitter side, there is another Kenwood TH31BT which has it's discriminator audio connected to a Comm-Spec tone decoder.  That in turn keys the General Electric Mastr-II mobile unit running 50 watts.  6m antennas on both ends are DB-212's that have modified for this frequency.

The equipment rack showing the 6m transmitter and link radio.  Listed from top to bottom, and left to right:  Scom 7K controller for the 146.805 Keene repeater, (you can just see the bottom edge of the actual .805 repeater MSR2000 cabinet sitting on top of the rack), below the 7K is the interconnect drawer.  Connections for all the ancillary equipment goes through here, then below on the left is the GM300, satellite receiver link radio, to the right the CDM1225 UHF remote base, below those is the 6M Mastr II control head, to the right is the Kenwood link HT that's listening to the EKW site, under those is the actual Mastr II 6M transmitter and finally, the Astron power supply.

Update: Finally, the repeater was brought back down to have the 220 links replaced with UHF radios.  

The repeater link radio were replaced with a couple Johnson Challenger radios (thanks to Arnie - N1BAC for the donation of those) and then several weeks of tinkering to modify, reprogram and retune them down into the ham bands.  This naturally let into another project on how to modify those radios.  There was "some" information on the web about them, but not much.  So..... that ended up causing the creation of yet another web page devoted to the mods for the Johnson Challengers.

6M receiver with the new UHF link radio.

Once both ends of the split site repeater had the links on UHF as opposed to the 220 portables, we had to get them back up the mountain.  The receive end was easy, as that lives at the NHPTV CH52 site, same as 443.8.  I got that on the air in about an hour because I also had to replace the 220 with a 440 to point at Hyland Hill.

So on Jan 13, 2007, Dale (N1NCI) and I made the trip up Hyland to put the transmit end back up.  We were able to drive about half way and then ran into too much ice on the road for the truck, so we hiked the rest of the way.  Dale needed to move some stuff around in the building to make more room for another rack of microwave stuff, so he was planning on moving all the amateur stuff into a taller rack to reclaim some floor space.  Dale carried an unassembled 6 foot steel rack and I lugged the 6m transmitter up.  We weren't able to bring up much more stuff, so what we were able to accomplish was limited.  Once we got there, we put the rack together, completely disassembled and moved the 146.805 repeater into the new rack, re-installed the 53.73 transmitter and all the other junk that went with both repeaters, turned stuff on, made a couple tests and walked away -- well, hiked back down.  We pretty much only guessed stuff was working.  Of course when we returned back to the city, we found out that the 6m transmitter could just about be heard, and the link from Derry Hill was pretty deaf too.  No 6m repeater today...

On Jan 26, 2007 around 9pm, Dale called me and said pretty much the usual...  What ya doing tomorrow?  So another trip up Hyland was planned for the following day.  Of course the outside temperature at the time of the phone call was exactly 1 degree.  And they weren't supposed to get much warmer than that the following day.  We met at about 9am to begin loading up test equipment and other potentially needed stuff for the trip.  Because we've now developed a problem with the 2m repeater.

OHRV off the trailer

All loaded up and ready to head up the hill.

Once we arrive, we begin testing antennas.  The 6m repeater works fine, as long as you're standing next to it.  The transmitter isn't putting out - or should I say, can't be heard, and the UHF link can't hear the other end.  The first test pretty much tells us that there either isn't an antenna at the end of the feedline, or it's a dead short.  That turns out to be the pigtail from the heliax to the transmitter is shorted.  Replaced that and the 6m transmitter is loud and clear!  Putting out just under 50 watts into the antenna that's almost flat at 53Mhz.  The service monitor tells us that the UHF link radio is hearing fine.  The antenna analyzer tells us something else.  No antenna at the end of that feedline, so we move that around onto the link antenna for the 2m satellite receivers and it now hears the other end great.  Funny how radios play so much better with antennas!!  Go figure....  Okay, so the 6m repeater is now officially on the air -- again...

The new rack, 2m MSR2000 sitting in bottom.  Power supply for 6m transmitter and all link radios above that, 6m GE Mastr-II transmitter, Control head on left, Challenger link radio on right and 5K controller above that.  Then the 2m interfacing shelf, 7K 2m controller and link radios above that for the 2m repeater.

Close up of the 53.73 transmitter and link radio.

53.73 transmit antenna mounted way above the trees on the new tower.

Update: On July 26, 2015, 53.73 was brought back from the dead. It had been off the air for actually, a few years at this point. My goal for the summer, if I did nothing else, was to get it going again. And I've got to say... Mission accomplished!!

So, I'd been talking with Dale - N1NCI about making a run up Hyland to work on the TX side of the house. Once we got both our schedules lined up, we made that happen. Going back about a month, I had a Low Band Motorola CDM750 kicking around that I wanted to use for the new receiver, of course the first thing that I needed to do with that, was get it programmed out of band so that it would actually cover 6 meters. I really didn't even care if it transmitted, because I was just going to use it as a receiver anyway. It took me a while to get all the information that I needed to actually accomplish this, mods to program CDM's out of band., but I did. And it works pretty damn well! And it "does" transmit!
Okay, so I rebuilt the receive end with the new CDM750, and swapped out the UHF link transmitter with a Motorola Maxtrac. I grabbed one of those little "repeater builder" widgets and pretty much just jammed the CDM receiver audio down the Maxtrac's throat. Programmed the Maxtrac to transmit whenever the CDM receiver became active and we were off and running. At least on the receiver end... Now off to the transmit end.

When we got up on Hyland, naturally, it had started to rain, and because of the "logging" operation along that goat path of a road, things were a bit... ummm.... muddy... But we made it without much trouble.
Once into the radio building, we took a glance at the poor old neglected GE Mastr II that's the low band transmitter. It all was still powered up, but it wasn't doing much.

First test, let's just see if I talk on the UHF link frequency, will that cause the controller to wake up the 6m transmitter... Trust me, it was a very quick test... answer.. Oh Hell No!!

No worries, that poor old Johnson Challenger isn't worth the effort to even trouble shoot. So let's ditch that thing. I had brought up a new, well, new to this project, Motorola M1225 to use as the new receive link radio. Donated by the local Motorola shop, --Thanks Jeff at R&R Communications -- !!
I had programmed up the 1225 and wired up the interface cable to the controller to be pretty much "plug 'n play", or so I thought. What happened next was that the COR never changed state and the TOR was inverted. No biggie, pop the top off the 5K controller and change the dip switch.. ya... that didn't work... So. Rather than waste a lot of time trying this and that, I decided to just grab the whole mess and bring it back to the house so I could "bench it" and actually work on it.

Dale and I traced out my connections, which were correct, but something still wasn't quite adding up. So, Dale undid the DB25 hood on the controller end of my cable, and what do you know... I had put a MOSFET inside there, that I had completely neglected to document, which was used as a buffer so I wouldn't load down the Johnson radio. Removed that, and everthing, and I mean everything fired right up and took right off!! Back up the hill we go. At least now, the sun had come out so it wasn't going to get any muddier on the ride up.

Got back up the mountain, re-mounted stuff in the rack, and called the stations that we had lined up to help us with testing and could hear them coming across the link radios just fine. The 6m transmitter came up and we thought we were golden, except for one minor detail.... nobody could hear the 6m transmitter! It worked fine at the house, but once back on the mountain, nothing... Great, we've got a low band antenna failure. So, we start tracing heliax runs so we can put the antenna analyzer and TDR on it. The results of those test were less than flattering... However, turned out that the line from the transmitter to the polyphaser lightning arrester had been moved, and really wasn't connected to anything. So, reconnected that, and well... the rest is history now. IT LIVES!!

So we've been running tests to check for coverage, and it's pretty good, even for a split site! I still need to make a few audio adjustments, but overall, very pleased with the results. Below are a few more pictures of the current system. Enjoy!!

Keep checking back for developments and progress of the pending WA1ZYX/R 6 meter Keene Machine.

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