A calculator for bad radio.

BOS-channel number. Enter and frequencies are calculated. Now with support for the new TETRA radio.

Note: When the radio traffic type "Intercom (duplex)", each channel has two frequencies, one in the upper band and the lower band (here the relay station transmits) (here sends the mobile subscriber). With a duplex switch equipped radios allow simultaneous transmission and reception (full-duplex), since both parties are using their own frequencies. A possibly connected to the relay station via radio link control station to the mobile subscriber can fall into the word, it has a priority circuit.

Sends a participant, for example, on the lower band and receives on the upper band it is called "Intercom sub-band" (GU), but it sends to the upper band then this is called "Intercom Upper Band" (GO).

(Source: Wikipeida)