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To: GingisK
I'm using a 7db Yagi if I remember correctly. I started making my own. It is basically a copy of a commercial unit I had. I don't have too much trouble with line of sight where I am, and the applications I have been targeting are all fixed base locations with either a tower or a pole to get it up above the ground clutter.

I am intending to use a large building in the center of town with a 50' tower on top of it to give me a fairly good line of sight to all my distributed units.

For that location, I have a commercial stacked co-linear array with a gain of about 13db if I remember correctly. I also intend to put the RF module right at the base of the antenna instead of using heliax. Too much losses at those frequencies. I'm going to talk to it through cat 5.

For my distributed units, i'm building the RF module right into the Yagis. At 900 mhz, coax has a lot of loss. Putting the transceiver right at the antenna allows the best output power and receive signal, and the data can just come down the cat 5.

If you are trying to do it through coax, you need to look at your losses. You will probably lose most of the signal both ways if you have any significant length of coax/heliax.

Line of sight is pretty much necessary to get a distance of 10 miles at that band.

43 posted on 05/20/2023 10:09:20 PM PDT by DiogenesLamp ("of parents owing allegiance to no other sovereignty.")
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To: DiogenesLamp

Understood. Thank you for your advice. It did occur to me to put the radio at the antenna, I just didn’t do it. Now I’ll give that a try.


44 posted on 05/21/2023 5:31:46 AM PDT by GingisK
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