Quite often the cause of this symptom is desense, due to the close proximity of the radio you are listening on. the VX-7R very well may be overloading the receiver of the Terra. Try instead to list the help of another ham. Your VX-7R may be working just fine. The Terra may not have the front...
We use M12 connectors on our mining, heavy and light rail products. These are applications that require high reliability, and are placed in high vibration environments. We have had no issues with them. These applications are for "drive by wire applications" that have SIL2 certification.
The Reecom radios are far superior to the current Midland offerings, and if I understand your requirements correctly, the R-200 and the R-500 meet most of your requirements, including the multi-channel scan.
You can purchase a spring from Larsen for the NMO-2/70B. Just remove the same length from the bottom of the antenna as the spring adds. I have one on the roof of the current truck for 10+ years. No impact failures, great range. Larsen is a great commercial/public safety quality antenna.
Most of my programming issues with this same setup (I have used VX Commander with two VX-7Rs for many years) were solved by the following sequence:
1. Connect radio.
2. Bring up radio into the program reading mode using the specified key sequence.
3. Read the radio.
4. Save the file; do NOT...
I can fully recomend the Larsen NMO mounts and antennas. I use the mounts for 10m, 6m, 2m, and 70cm on the roof of my 2005 F150. I use the the Larsen NMO27 for 10m, NMO50 for 6m, and NMO2/70 for the 2M and 79cm bands. The 10M antenna has received a lot of use over the past few weeks. The band is...