SOUTH300
Member
I just recently re-installed a MCS2000 Model II VHF from one vehicle to another. 2008 F-150 to a 2009 F-150. I am currently using a Diamond K-400 Trunk Lip antenna mount and secured it to the bed rail. In the old truck, it worked like a dream. In the new truck, this is what happens:
On certain channels, not all, the radio will attempt to key but then stop after about one second. If you hold the PTT, it will continuously try to key. It appears that it does x-mit, because it will hit the repeater for a second. The tail sounds clear. The Transmit frequencies are in the area of 154-158 mhz. However on some channels in this range, the radio appears to transmit fine. In fact, I can hit repeaters that are 30-35 miles away, and sound clear.
Here is what I have checked:
Power and ground to the Radio are good.
The K-400 appears to be grounded good to the bed.
I ran a separate ground from the antenna to the frame, and problem still exists.
When I unscrew the antenna from the K-400 mount, the radio DOES key. (I know you are not supposed to do this)
The problem returns when the antenna is screwed back on.
I have tried two separate antennas on the K-400, one adjustable, and one non.
Sometimes when the radio is on low power, the radio will key, but will not key when it is on high power.
This leads me to believe it is an antenna issue, but I cannot figure it out.
Open for any suggestions. I do have the CPS/Tuner but no test equipment.
Thanks
south300
On certain channels, not all, the radio will attempt to key but then stop after about one second. If you hold the PTT, it will continuously try to key. It appears that it does x-mit, because it will hit the repeater for a second. The tail sounds clear. The Transmit frequencies are in the area of 154-158 mhz. However on some channels in this range, the radio appears to transmit fine. In fact, I can hit repeaters that are 30-35 miles away, and sound clear.
Here is what I have checked:
Power and ground to the Radio are good.
The K-400 appears to be grounded good to the bed.
I ran a separate ground from the antenna to the frame, and problem still exists.
When I unscrew the antenna from the K-400 mount, the radio DOES key. (I know you are not supposed to do this)
The problem returns when the antenna is screwed back on.
I have tried two separate antennas on the K-400, one adjustable, and one non.
Sometimes when the radio is on low power, the radio will key, but will not key when it is on high power.
This leads me to believe it is an antenna issue, but I cannot figure it out.
Open for any suggestions. I do have the CPS/Tuner but no test equipment.
Thanks
south300