727DSC OPERATION12345678910111213141516When the optional MA-500TR CLASS B AIS TRANSPONDER isconnected to your transceiver, an individual DSC call can betransmitted to a selected AIS target, without needing to enterthe target’s MMSI code. In this case, the call type is automati-cally set to Routine.See page 102 for connecting instructions.To ensure correct operation of the DSC function, makesure you correctly set the CH70 SQL Level. (p. 71)Step 1: Transponder’s operationSelect a desired AIS target on the plotter, target list or dan-qger list display.• You can also go to the next step whenever the detail screen ofthe AIS target is displayed.• Make sure the transceiver is in the normal operating mode. Oth-erwise, you cannot make an individual DSC call using the tran-sponder.Push [DSC] to display the voice channel selection screen,wand then push [Y]/[Z] to select a desired voice channel*.• Voice channels are already preset into the transponder in recom-mended order.* When a coast station is selected in step q, a voice channel willbe specified by the coast station, therefore you cannot changethe channel. The transponder will display “Voice Channel isspecified by the Base station,” in this case.Push [DSC] to transmit an individual DSC call to the AISetarget.• If Channel 70 is busy, the transceiver stands by until the channelbecomes clear.• If the transceiver cannot make the call, the transponder will dis-play “DSC Transmission FAILED.”Making an Individual call using an AIS transponder■Transponder’s display Transceiver’s displayTransponder’s display Transceiver’s display