Passive Repeater: 2 antennas directly connected to go around obstacles

[Onebit]

Hi,

I'm going to make some testing with a passive repeater. This means a simple flat reflector or two antennas connected without electronic. I'm going to test with two antennas.

I have found an very old (1969) but interesting article about microwave reflectors here:
http://long-lines.net/places-routes/Thurmont_repeater/EW0569-fc.html

Perhaps someone of you has already made some experiences. Please write if you have knowledge.

I would like to know how to calculate with passive repeaters (mainly with two antennas) and how they affect the link quality and range.

Of course I will also write my testing results!

Best regards,
Franz Boehm

[therealboss]

Found this on Google

http://www.valmont.com/asp/communication/specialty_structures/asp/passive_repeaters.asp

[lonnie]

In general the results will be poor. The guys who have done this will always use huge dishes to focus the signal on the relector and their power levels will be in the 200 Watt range. The will also use a large reflector or antennas to gather at the mid point and a large antenna to beam it to the other end.

You can try, but when you start out with less than 30 dB versus 53 dB and have 32 dB antennas as opposed to 45 dB you can see your signal levels are starting to look pretty tiny.

I wish you well, but I am also pretty certain you will end up with an active repeater and Solar Power.

[Stratolinks]

Only way I have seen thsi work very well at all is with an antenna with a waveguide feed that has been directly attached to another antenna with a waveguide feed. That means no cables of any kind between the 2 antennas, just a waveguide. At any rate, it is a rather lossy setup at best, but in certain unique situations can do the job.

[Skaught]

The national railway here in Canada has several of these in the mountians not far from me.

They use minimum 16 foot antennas typically and many hundreds of watts TX.