SASKATOON, SASKATCHEWAN,CANADA
October 12, 1997 was an important day for Saskatoon amateur radio. This was the day the VE5EMO ATV repeater went on the air.
Bruce VE5BNC, Gus VE5SPI, Brian VE5MKV and Bob VE5RGM (not in picture) assembled
at Luther tower at 1:00. We were certain that in a couple of hours
the repeater would running and our remote testers Lee VE5LEE, Dwayne VE5HZ,
and Bill VE5DN would be giving us P5 signal reports.
Well, "Murphy" came along (uninvited) to help us and by 5:00 we still didn't know whether the repeater had survived the install. More about this aspect of the story in a moment but first a brief description of how the repeater project got started.
In 1995 Dwayne and Bob got interested in amateur television. Talk led to action and a couple of ATV transceivers were purchased. In Canada there is only one 70cm frequency allocated to ATV, 439.25 MHz, so our choice of frequency was easy. Soon others joined in and the Saskatoon Amateur Radio Club supported the establishment of an ATV repeater. The project did not come together however, until the Saskatoon Emergency Measures Organization (EMO) got involved and Don Litz, the co-ordinator, was able to secure some funding to put the repeater on the air.
Block Diagram
Bruce was the person who foolishly
volunteered to assemble collection of parts into a repeater. The
receive side of the repeater consists of PC Electronics ATVR-4 receiver
on 439.25 MHz with a VOR-2a controller and an Elktronics ID board.
In order to help prevent desensi
Bruce was responsible for organizing communications for the MS Society's Super Cities WALK
in 1998. As it turned out the ATV repeater was ready for a real life
test about the same time as the WALK so Bruce seized the opportunity to
incorporate ATV into the communication plan. The repeater was set
up in the Saskatoon Amateur Radio Club’s communication trailer and installed
at a central site. Needless to say, the volunteers who put on the
MS WALK were impressed by the quality of the pictures and with three camera
positions we gave good coverage of the entire route.
With the preliminaries out of the way we can turn back to October 12.
October weather in Saskatoon is unpredictable. The morning started
off with a few snow flakes which later turned to a light rain. By
noon all we had to contend with were high winds and cold temperatures.
Of course, our inside work went fine. The repeater was installed
in its bay in the radio room atop Luther Tower and the hard line was fed
outside. At this point Murphy joined the crew. The mast clamps
proved to be too small so Bob and Brian went Sunday shopping for replacements.
Meanwhile Bruce and Gus continued to work at the site. By the time
the shoppers returned, the door knob on the access door to the roof had
jammed. We were locked inside the building. Luckily
there was no one on the roof at the time! It took us the better part
of an hour to finally "persuade" the door to open.
Outside the wind was gusting to 70km/h. There is nothing like being strapped to a tower with a wrench in your hand, 23 stories in the air with the wind blowing so hard you have to lean into it to stand up. None the less, the antenna took its proper place on the tower and by 5:00 with the hard line connected we were ready to try the repeater. Unfortunately, by this time the crew had to abandon the project for (Canadian) Thanksgiving dinner. Right after the local area two meter net the next evening Bill VE5DN announced that we would be holding our first ATV net on the new repeater. Everyone was able to get into the repeater with no problem and generally good signal reports were being exchanged.
Since our first foray into ATV, much has changed. In the summer of 1999, the antenna fell victim to the notorious Saskatchewan winds. Vibration had caused the mounting bolts to come loose on the antenna and it plunged 20 feet to the roof of the building below, taking the end of the feed line with it. When we put it back up, we included a liberal coating of thread lock compound and a steel clamp over the set screw.
In the spring of 2000, we brought the repeater down for a few weeks to give it an upgrade. We added an 8 pole DCI 439.25MHz VSB filter on the input to eliminate some interference from a local paging service. We also added a preamp on the input to help boost the sensitivity. Our major upgrade was to rebuild the controller to include 4 A/V inputs, enhanced capability to enable and disable the repeater and the necessary controls for the planned tower camera. To appease Bob we also included several LED's on the controller, some of which even blink!
We also changed the repeater call sign from VE5EMO to VE5ATV. Along with this, we re-burned the EPROM in the video ID board to display a skyline of Saskatoon on one of the ID screens. New ID Screens
|
Input 439.250 Mhz AM Output 1277.250 Mhz AM Co-ordination and control 144.340 Mhz Sponsored by Saskatoon EMO and The Saskatoon Amateur Radio Club |
If you have any questions regarding the repeater or this page please contact us at:
ve5aa@rac.ca.
Return to SARC Home Page
