User Manual

MT-4E VHF & UHF Receiver & Transmitter Instruction Manual
IM08-MT-4E-TXRX Project 1106
Hardware Tuning and Troubleshooting
22
SYSTEM TROUBLESHOOTING
If the radio system is not receiving or transmitting on the right frequency, check the Channel and Bank
select lines of the Receiver and Transmitter modules. The Motherboard has jumpers that allow one of
16 channels to be selected on a receiver or transmitter. The factory default is to have them all set to
ground the channel select lines CSEL0-3, forcing the radio to operate on channel 1. On the receiver
and transmitter there is also a Bank A/B line which usually oats high selecting Bank A. The receiver
and transmitter have separate control of their channel select lines, so changing receiver channels
does not affect the transmitter channel.
If the Radio Service Software is failing partway through a read or write of the receiver, check that the
receiver is not squelching and unsquelching repeatedly during the read or write operation. Disconnect
the RF signal source from the receiver during the read or write operation.