I have a PSR 400.When I turn the unit on,sometimes it won't go into trunking mode.I have reprogrammed the radio many times.Power supply good and antennas are good.I have tried different styles of antennas.And have also parked very close to the local control channel tower.All other radios are working fine.Was wondering if anyone has run into the same problem?I opened the scanner,antenna connection is good and solid.