If the frequencies at the receiver and transmitter are matching, but there is no RF please check the following:
- Are either of the units in RF Mute? (press the power button quickly - RF mute is displayed - select "RF MUTE OFF"
- Are the antennas connected to the receiver? - the receiver should have two antennas connected to the BNC sockets marked 'ANT I' and 'ANT II'

Are you in range of the receiver? (less than 30m and line of sight is a good starting point)
If you have more than one system you can do some extra troubleshooting:
- check the transmitter with another receiver? If it's working there then you may have a fault with your receiver, or need to check the squelch and pilot tone settings again.
- check the receiver with another transmitter? If it's working ok then your transmitter may have a fault.
Are your receivers connected to an antenna distribution system? If so, try disconnecting them and connecting antennas directly to the receiver? Does it work now - if so the antenna distribution may be faulty