Kenwood TK-780 Programming Instructions Manual

Contents

9Understanding Base Channel ChangeIn order to understand the operation of data channel change you have to realize that themobile units are using a dedicated PassPort/LTR ID code for data and a separatePassPort/LTR ID code(s) for voice communication. When the MDT sends a message, themobile radio is switched to the defined data PassPort/LTR ID; after the transmission iscomplete, the radio reverts back to the voice ID code. The 2016 base unit receives andresponds on the data PassPort/LTR ID code.A problem arises when the dispatcher needs to send an outbound message (e.g. GPS Poll,Text Message, Horn Honk, etc.). At most times, the mobile units are idle and thereforeon the voice PassPort/LTR ID code. When a message from the base is sent, it is sent onthe data PassPort/LTR ID code, thus the targeted mobile unit does not receive thecommand from the dispatcher because it is listening on a different PassPort/LTR ID code.To overcome this obstacle, the 2016 can be configured to change to the voicePassPort/LTR ID code when sending outbound, base originated messages. As with allbase modem installations, a dedicated radio is required for the 2016 base modem.Configuring your 2016 for Voice Channel ChangeThere is a simple wiring harness change is needed to enable the 2016 to activate thechannel change line out of the 2016 Base Modem. From the 2016 wiring harness,connect the Teal wire ground. This activates the Grey wire as the Voice Channel Selectline.Crimp a Molex pin onto the Grey wire from the Pyramid Communications Model 2016wiring harness and connect to the Kenwood KCT-19 Pin 15. See figure below of Molexpin layout.Grey Wire to Pin 15