Radio Frequencies

[CollinNiemerg]

What is the closest a radio frequency can get to another frequency without them overlapping and being able to control one another?

 

[nd5y]

It depends on the type of modulation used, the quality of the receiver and signal strength or how far the transmitter is from the receiver.

 

[CollinNiemerg]

I work at a coal burning generating station, and we have RC Cranes throughout the plant. I have to make a recommended guideline for the frequencies so that when contractors come in with their own radio frequencies they won't interfere with ours. There are 9 cranes total with the following frequencies: 314.8475 MHZ, 914.150 - 915.875 MHZ, 465.7125 MHZ, 921.9 MHZ, 908.90 MHZ, 904.10 MHZ, 908.70 MHZ, 905.50 MHZ, and 911.00 MHZ. Do you see any possible interferences with those frequencies.

I am very green to all of this information so bare with me please.

 

[GrayJeep]

The spectral purity of the transmitter is a factor as well. (CB easily demonstrates this factor)

OP- what are you trying to do?

 

[nd5y]

We still don't have enough information to be of much help except to say that keeping both the frequencies and physical separation as far as possible should reduce interference. What power levels and emission modes do they use?
The 900 MHz ones may be digital spread spectrum and be able to tolerate multiple signals from other units plus all the other crap in that band.
You should consult the manufacturer of the crane control units or their documentation and see what they recommend.