Batboard

Do these so called passive repeater antennas really work? The ones I've seen are for cell phones in cars. There just two glass mount antennas, one outside, one inside, connected by coax.

Can I do something like this for Vhf/Uhf. I work in a steel building and can't recieve anything. Can I mount a antenna outside and one inside to help my recieve. What is the range. A repeater is not possible. Any ideas?

There has been many attemps over the years to do just what your asking. Many road tunnels today have an active amplifier system installed. If all your trying to do is recive,then maybe you can consider installing a line amp to make it work. You just need to make sure that the doner antenna needs to have isolation from the amp output antenna. If there is not enough isolation for the system, then the amp will desence the amp.

Use a good piece of cable like 1/2 heliax. This gives the best low leakage between the in and out. Best to use some form of directional gain antenna for the input. Would be nice to have a pass filter on the input of the line amp. Use good coax for the output of the amp that goes to the inside antenna or antennas.

Hope this gives you some thought on the subject. If you went out and bought a system like this, it would run between 1k and 2k. You could build one yourself if you had some time and could obtain the parts.

Jim

We have delt with coverage problems in buildings by installing a Yagi or corner reflector antenna pointing to the repeater, and another 1/4 wave antenna inside the building. You have to use real good cable, no RG8 crap!
This is a Passive Repeater. Originally used on microwave line of sight to go off at an another angle to the station. It is two dish antennas back to back so to speak.

Here are the requirements:

Incredibly strong donor signal (-45 dBm). And then you might be able to get coverage within a small rerad room. If you have only -85 dBm which is a great signal outdoors, you will find your rerad coverage to be only about 3 feet from the antenna. Try this with your home or shop base station antenna, and see how far from your basement rerad you can see a difference on your HT. Passive rerad is easily accomplished at cellular and above as antennas have much higher gain characteristics to make it work.

OK thanks. I wan't sure if that was possible or not. I've seen some products but never belived they would work. I need to recieve multiple bands at work so a repeater would not work. I even have troubles picking up my 5 watt Uhf vehical repeater thats only 200 feet away. I could probably put up two of these at different ends of the building, with a recieve amp and some 9913 coax. I think with all the metal inside, 10 feet might seperate the antennas good enough.