824-896 yagi antenna

[c55399]

I have a yagi antenna which i suspect is meant to be used on cellular network. I was able to found that she have a 6.5db gain. On the sticker there is a model number (F-3884) and also the frequency range (824-896). There is a TNC connector. I tried to google it and found nothing. I would like to listen to a motorola p25 system in the 866mhz. I was wondering if it worth to buy the adapters and cables to fit the antenna on my bcd396xt.

Thanks

 

[benbenrf]

C55399

Go for it, why not - 866Mhz falls bang in the middle of your antenna bandwidth - you should enjoy good Gain. Added to the Gain will of course be the reduction in noise and the improvement in noise ratio that you will enjoy.

The downside of course - and you will no doubt know this - is that you are going to have to continualy redirect/repoint the antenna towards the signal origin and will lack the ability to enjoy omni-directional coverage. But so long as this is not a problem (i.e. you know the position of the tower you wish to monitor and any mobile P25 you may wish to listen to lies within the beamwidth) for you, I'd say it was definately worth it.

You could compliment the Yagi with an omni-directional antenna - switching it in/out of the signal chain as you want, once you have the Yagi pointed in the correct direction, or keep it "on" to monitor a tower while following a mobile moving P25 transmission.

I'd go for it - whats it going to cost you? Coax and some connectors. So what if it turns out to be impractical, you could always use it at some later stage mounted at home to a mast. P25 is going nowhere - its here to stay for a good few years I suspect.

 

[c55399]

Thanks for your reply.

What would be my best choice to connect the TNC female connector on the antenna to the SMA female connector on my scanner. Knowing that:

1- I would like to install the antenna on my roof an the scanner is in the basement wich mean 50 feets of cable.
2- I don't have the crimping tools to install the connectors by myself.

Thank you again.

 

[WayneH]

That looks like a female N connector and not a TNC.

 

[Rt169Radio]

What is it made out of? It looks like heavy duty metal. Am not sure if depends on what coax for 800 MHz but RG-8U and LMR-400 is good for coax.

 

[benbenrf]

What is it made out of? It looks like heavy duty metal. Am not sure if depends on what coax for 800 MHz but RG-8U and LMR-400 is good for coax.

... I was wondering that as well. Initialy thought aluminium then looked again and thought perhaps galvanised mild steel(?) - which would be unusual for an antenna that small. Extruded alloy main arm with alloy tubes for the folded dipole and radiators/director is the usual material

 

[W2GLD]

What is it made out of? It looks like heavy duty metal. Am not sure if depends on what coax for 800 MHz but RG-8U and LMR-400 is good for coax.

I would use at least LMR-400 or better; the loss factors @ 800MHz. on lesser coaxial cables are too great and would negate the gain performance of the antenna. Generally for less than 100', LMR-400 is a good choice for your installation. Also, if you know how, you can simply but the correct connectors for each end and negate the need for adapters; bear in mind, each connection point introduces additional losses, by not using barrel connectors, adapters, etc. you're getting the most out of your antenna installation...

 

[N5TWB]

... I was wondering that as well. Initialy thought aluminium then looked again and thought perhaps galvanised mild steel(?) - which would be unusual for an antenna that small. Extruded alloy main arm with alloy tubes for the folded dipole and radiators/director is the usual material

If you want to know for sure, grab a magnet and check but my money is on it being all aluminium (note the culturally-sensitive spelling) except for the N-connector.