Newbie "Yagi" questions

[kc8qln]

I already understand 800 Mhz Yagi's are directional, they need low loss cable, and they need to be up as high as possible. So here is my questions;

1. Will they work in an attic? I can get one in my attic and my listening room is directly below it, so I only need maybe 20 feet of coax at the most.

2 If I have a Sounth and East system, I am trying to hear, can I buy 2 and pre-position them apart from each other? (I don't have a rotor). Then have 1 scanner dedicated for each system?

Thanks

 

[ka3jjz]

1. So long as there's not a lot of metal in the way, I don't see any reason why not. Of course, putting up anything in the attic in this season is a very hot task, hi

2. Again it should work, so long as spacing is maintained. Since a full wave seperation at 800 mhz is so small, it's possible to put them on the same pole and they would likely still work.

73s Mike

 

[Al42]

There's an old ham trick. Mount the antenna on a mast long enough to stretch from around your window to above the roof line. Use an under-eave mount or wall mount to mount the mast, but don't over tighten the mount, so that the mast can rotate if you give it enough torque. (You might even want to use a rotator thrust bearing at the bottom of the mast.) Clamp a Vice-Grip on the mast and you can rotate it by opening the window. (It's called an "Armstrong" rotator.) Cost is about nothing if you already have a Vice-Grip.

 

[nexus]

KC8QLN, yeah that should work. There are a lot of people with antenna restrictions who mount antennas in their attic. But it won't work very well if you have a tin or metal roof. So if you got wood and shingles you should be ok. Oh and height is not that big of an issue when you're dealing with a unidirectional antenna for receiving. 15 feet or so up would be sufficient for 800mhz. Of course higher is always better, but with a 5 or 8 element yagi up say 14 feet in an attic just simply pointed in the direction of the transmitter should do the trick.