I am looking into installing an STL system with a repeater on a building about 2 miles from our studio. The question I have is how much seperation is needed between the transmit and receive frequency at the repeater without using cavities. The antennas can be about 80 feet apart and will be pointed almost 180 degrees apart. I know this will vary with different brands of equipment. Any suggestions?
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Another STL Question
- Thread starter rew
- Start date
That will probably work just fine if you can separate the receive and transmit frequencies by several channels.
Example #1 (mono path--16 miles, for AM station to FM station transmitter site then 2 miles to AM transmitter site) Receive: 944.5, 200' AG with Marti 4' dish, transmit 947.5, 15' AG into Scala PR-450 U.
There are two other STL transmitters at this site using 6' dishes, 160 degrees path difference but near the same elevation as the receive antenna. This required putting in the 10 db pad on the STL10 receiver, but works fine now. The other transmitters are at 949 and 951.5.
Example #2 (Composite path--25 miles, for FM on channel booster) 951.5 in to 8' dish at 150' AG receive, transmit at 50' into Anixter Mark small parabola at 947.5). The transmit here is at 3 watts for a short path.
Example #1 (mono path--16 miles, for AM station to FM station transmitter site then 2 miles to AM transmitter site) Receive: 944.5, 200' AG with Marti 4' dish, transmit 947.5, 15' AG into Scala PR-450 U.
There are two other STL transmitters at this site using 6' dishes, 160 degrees path difference but near the same elevation as the receive antenna. This required putting in the 10 db pad on the STL10 receiver, but works fine now. The other transmitters are at 949 and 951.5.
Example #2 (Composite path--25 miles, for FM on channel booster) 951.5 in to 8' dish at 150' AG receive, transmit at 50' into Anixter Mark small parabola at 947.5). The transmit here is at 3 watts for a short path.
at 950 you're looking at around 30db of isolation by doing that. 
It's certainly worth it. Keep in mind also that some partial type/ lawnchair type won't pass horizontal (the radiating element) but will if you go vertical with it due to unwanted side lobe scatter, etc.
It's certainly worth it. Keep in mind also that some partial type/ lawnchair type won't pass horizontal (the radiating element) but will if you go vertical with it due to unwanted side lobe scatter, etc.- Status