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Posted by Bret on January 05, 2001 at 20:38:32:
In Reply to: Re: Long Range Trunking posted by Jack on January 05, 2001 at 18:41:45:
Hello,
I use a 7 element 800mhz Celwave Yagi for long haul trunk monitoring here in Florida. Here are a couple of issues you need to consider:
800 mhz Frequency Congestion - Here in Florida we are inundated with 800 systems. Successful control channel lock is sometimes impossible because of co channel interference. Other times you will be able to follow the transmissions and will have a interference from another system's frequencies on the active voice channels. This makes for alot of frustration here.
Power lines - Nearby power lines attenuate weak 800 reception- if you cannot get the antenna over the lines in height go under them. This can make a big difference.
It has already been recommended but I'll say it again good cable makes all the difference in the world. The major thing to absolutely stay away from is PL259 - SO239 connectors and adapters - they are useless above VHF and even marginal there. I use nothing but BNC and Type N.
Get a good antenna book (ARRL Antenna Handbook)) and study antenna designs. Antennas are simple and fun to build yourself and you can save a ton of money in the process.
For local trunking reception don't get caught up in the gain antennas fad. They aren't needed and enhance cellular/iden interference. I use a simple homebrew quarterwave duck that works great and is less than 3" in length and flexible.
I hope this helps,
Bret
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