Question Concerning Yagis

[jasonscottlewis]

Im fairly new in the scanner trunking. I have a Uniden BCD996P2. I’m looking for a Yagi that will work well with this scanner. I can pick up to about 30 miles on my telescoping antenna, but it doesn’t pick up the GM factory frequencies that I know uses MotoTrbo. I’ve taken my scanner into work and scanned the frequencies, so I know there are active LCNs. Any suggestions?

 

[chief21]

I don't have any suggestions for a yagi, but you should consider that many factory radio systems are engineered only to cover the factory floor and the immediate surrounding area. Unlike "wide-area" radio systems that are intended or required to provide coverage to complete cities or counties, this may make a factory radio system signal difficult or impossible to receive many miles away. Certain systems have been known to use very low power and "leaky coax", rather than a typical external antenna, so that the radio signals are intentionally limited only to where they are really needed.

 

[amemait]

looking for a Yagi that will work well with this scanner

A Yagi antenna is most efficient for a specific frequency, and usually has a fairly small bandwidth. And you didn't specify the frequency you want to monitor. Personally, I build my own Yagi antennas for ham radio, but purchased a Discone antenna for my BCD996P2 scanner.

If you're getting 30 miles out of a small telescoping antenna, an outdoor Discone antenna will probably work wonders for you. I'd suggest one that covers a sufficient range for what you want to scan. I'm using a 25MHz to 1.3GHz version with good results. Use a good low-loss coax (e.g. LMR400, pretty stiff, but good stuff) with N-connectors for best results at UHF frequencies and above. You'll need an adapter to connect to the scanner (i.e. N-type female to BNC male, most likely, but make sure you get the right one).

 

[W5lz]

The 'problem' with using a yagi or other directional antennas is that they typically are made for a fairly harrow range of frequencies. There's also a directional antenna for wider 'ranges' called a 'log-periodic', which is sort of a yagi. It's directional anyway.
Would any directional antenna be suitable for your use? I have no idea. You can get a wider coverage range with a simple vertical antenna just by getting it higher above ground. Lots of "but's" in this, you decide what you want...