The Ham Repeater

I wanted to tell a story which happened to me in my past life (i.e. my life in Canada).  In early 2005 and into 2006 Myself along with a few friends, decided to build ourselves a UHF amature radio repeater in Toronto.  The group which I will call the 'Shockers' (Shockers International Radio Club) wanted a special repeater which we could utilize with our own radios, and which would serve the GTA.  Of course there are many many UHF repeaters in Toronto, but their either very crappy, range wise,  or very popular and filled with spam, or grumpy old ham farts.

We wanted our own unpublished repeater, which we could use un-encrypted digital radios on, or maybe even create into a HAM LTR system!  At the time we were involved in some emergency response work, and also some 'private investigation' work (at least that is what we shall call it) and we didn't really want to talk on the popular repeaters.


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A Motorola UHF repeater we acquired for the project. This was on my bench in the Engineering shop at CFRB.

My former workplace was kind enough to donate a tower site; a very high roof top antenna site, in midtown Toronto, with line of sight in every direction for miles.  We already had a few very nice sinclair antennas, which were to be used, and we were able to acquire some very expensive coaxial cable (I forget which type).  We had several radios which we could easily turn into repeaters, but it was our Motorola expert who was able to acquire 2 fully functional Motorola public service repeaters.  The only thing we were missing was a duplexer at this point.

The duplexer would come in time however, promises of investment and such were made on all sides, into the funding for a duplexer.  None of them ever really came through however.  But none the less, that was a small issue.  Right now we wanted to do range testing on the site to see if it was worth further work and investment.  We had a lot of radios which could preform this test, however we did not have an antenna yet.  There were antennas on the tower, but they were VHF or they were UHF but already in use.  Therefore, we needed to install our antennas.  We installed an interesting array or a 2 bay Sinclair UHF folded di-pole.  We aimed the di-pole north, to get slightly better coverage to the North towards the Moraine.  Di-poles are supposed to be somewhat omni-directional, but they are off-center a little bit, so...   Anyhow, We also had a 2 bay pair of UHF Sinclair 7 element Yagi's which we also pointed north.  We wanted to cover the Yonge street corridor fairly well up past Aurora.


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The planned coverage is outlined on the map. The dots indicate actual reception of the test rig we were using.

We 'temporarily' attached the antennas to a supporting arm for another set of antennas (of course temporary becomes permanent).  Now, to run the coaxial.  The night we ran the coaxial was a Friday night, in mid November.  It was stormy with a some lightning reported in the area, and near freezing rain and medium to high winds.  However it was the only night the whole team could get together to work.  We had 2 people down in the 'shop' working on the controller for the repeater, while we had 3 people up in the rooftop maintenance areas helping to run the cable through the ceilings from our equipment room.  Then came time to pop the cable out onto the roof.  Let me back track a bit here however.  When we started this night, we did not know it was going to storm.  We had started pulling the cable and had gotten the long length of solid core cable up into the large elevator room, before we realized the weather was getting worse.  The building itself (maintenance and administration) were not aware of our install, so we couldn't just leave a coil of cable in the elevator room, precariously hanging over 600 volt turbines (which were spinning with exposed conductors while we were working above them).  We had to finish that night.  The nights were getting colder, and to stop working that night meant pulling out all the cable we had already run.  We acted fast and 2 of us (one was too scared to go out on the roof) got up into the roof,  the wind blowing and whistling while a distance away we could see lightning strikes.  Okay so it wasn't the smartest plan, but we were determined.  We quickly brought the cable up through the roof seal and re sealed it,    then we laid the cable up the tower,  coiling the excess (because it was a 'temporary' install, right?) and then we began to prepare the connections.  If you have ever fitted a RG-8 coaxial connector from scratch, you know how difficult it can be to get it clean and proper in a workshop / bench setting...  Imagine up on a roof, late at night, with a crappy flashlight, and the wind and rain pounding down on you.  We were able to get very nice clean connectors put on the cable, (after one failed attempt) and we then connected it to the antennas,  all the while the tower was whistling with static.  We weather sealed it with rubber tape and electrical tape, and then we quickly gathered the tools and exited the rooftop, glad to still be alive.


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The tower that we attached the antennas to. We were up here installing them as a storm was rolling in.

Late that night once everything was ready (minus a duplexer) we decided to do a base to mobile range test.  We had a few radios going.  One was a mobile radio which we were using in place of the repeater, since this was to be a simplex operation.  The others were handhelds and mobiles in the 2 range testing vehicles.  I stayed at the repeater site and acted as a dispatcher.  We had our handhelds on another repeater which we knew had good coverage, just in-case we lost touch with one of our cars.

So off they went.  One car went south into downtown, the other north up Yonge street.  Each circled counter clockwise at the fringes of the clear audio range of the tower.  Talking simplex we averaged about 25 to 30 miles on about 30 watts.  The downtown was spotty due to the high volume of buildings, but we expected that, especially with most of our antenna power aimed northwards.  The signal to the north was exceptional, until you hit the peek of the moraine.  However I am sure if you kept going northbound you would of eventually gotten the signal back again around Newmarket or Bradford.


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The temporary 'base' station set up, used to do coverage testing. The air gun was set to blow cool air, not hot air, as the radios were working about a 75% duty cycle.

I plotted the signals on a map I made of the range estimated which I calculated, and they were very similar.  The only lobe I got wrong was one lobe to the South East towards the beaches which was dramatically cut short, worse then the signal was Downtown in some cases.

During that time I was doing this testing I felt like a taxi dispatcher.  Both units could not hear each other, So I had to manually call each one every few minutes for a reading.  It was very fun and I could of sat there all night and kept doing it, but alas gas money was mounting, and it was getting late; 4 am.

All in all, it was a good night,  we got a lot done.  Had the group not fallen apart afterward due to infighting, I am sure it would of been a great repeater.  Yet another venture of mine which was ruined by petty dramas.

I hope you enjoyed the story, I shall write more stories such as this in the coming months.  Stay tuned!  Oh, and if you need a repeater site built,  just email me ;)