It’s official…
The 146.94 repeater needs a new antenna. Kevin, W4KEV, and I visited the 146.94 site on Memorial Day Monday. Kevin fine-tuned the duplexer to near perfection. It will duplex perfectly on a 50 Ohm load, but still would not do so on the repeater antenna. Upon closer inspection with binoculars, you can see that one of the dipole elements on the DB-224 antenna is obviously damaged. The other elements may be damaged as well, but if so they are not visible from the ground. However, with this type of antenna, one damaged element is all it takes. I’m sure this is the reason for the noisy signals and “desense” that has plagued .94 for the past several weeks.
So now what? It is possible to replace the one obvious defective element. However, please bear in mind that any trip up the tower by a bonded tower climber is going to be expensive. What if the repeater antenna has more damage, and we don’t find it out until after he has made one trip up the tower, only to have to make another? This would make it even more expensive, and .94 would still not perform as it has in the past. In addition, the repeater antenna is over 10 years old. I’m not sure of its exact age, as I brought it from another site when I installed .94 at the WIVK site in 1998. That’s at least 10 years exposure to some very nasty weather atop a 3000 ft mountain. Remember when the weather guys say things like…”more snow and ice in the higher elevations…?” Well, .94 lives at a higher elevation. I want to do something for .94 that will last a long time and justify the total expense that will be necessary.
So, it’s time to replace the antenna. Too many nets and emergency communications groups depend on .94. I will be saving sheckels and attempting to purchase an antenna in the very near future. I will have to shelve some of the other repeater’s needs that I had planned on for a while. But I consider this a high priority. I hope to have .94 restored to its original high performance standard soon.
On a related note, I also spent Sunday afternoon at the 145.17 site. I have determined that its’ interference issue is NOT the paging transmitters on site, but rather something external to the site. I hate to say this, but it acts a lot like the TV station interference I am receiving on .47 and that Todd has been plagued with on his 147.36 and 145.13. I do know that 145.17 works great on a dummy load, so that rules out a problem internal to the repeater. There are several of us repeater owners that can’t wait to see what happens on June 13th!! That’s the day after the DTV transition, and the problematic 5 MW UHF transmitter will be in retirement. It’s also the day of the
I spent some time Saturday at the 147.075 site. It was just a checkup. I sure know how to have a holiday weekend, don’t I? J
73 de Tim WB4GBI
Tim Berry WB4GBI (check out my website at www.wb4gbi.com)
Chief Engineer
Citadel Broadcasting of
WIVK-FM/HD1 WNOX-FM WNML AM/FM WNRX-FM WOKI-FM
Chief Engineer
Vol Radio Network
"Do you really want to know what's wrong...or do you just want me to fix it?
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