Saturday, 20 August 2016

Thoughts on installing the ham radio gear into the Maroon Monster...

OK... geeky posting, so if this bores the crap out of you, keep on scrolling down the page ;)

Right; I have a rough handle on how I'm going to be fitting my amateur radio gear into the Maroon Monster; there are two main avenues, and a couple of minor ones;

Major Method #1

Mount within the leaf-hand load space storage compartment in the 'boot' area, running the power from the connectors to the accessory socket mounted in the trim panel. The antenna cable would then run around the top of the tail door to the right side of the vehicle.

Major Method 2.

As per #1, but in the right-side , the power running from the fusebox forward of the drivers seat, the cables running along the lower trim into the storage compartment. The antenna cable would run from the radio to its mounting point (see below)

Minor Point #1

The antenna would be mounted via a through-body New Motorola mounting system and a connector converter to the pl-259 VHF connector on the base of the antenna, preserving watertight integrity of the body of the vehicle. A hole would have to be drilled in the bodywork to facilitate the NMO mounting to be fitted.

Minor Point #2

Utilise my existing boot mount, the cable running from the load space storage compartment between the trim and the body panel, to the tail door, onto which the boot mounting would be fitted. Special care would have to be exercised to ensure as water-tight a fitting as possible, given that the antenna cable would be running on top of the door seal strip, presenting a possible ingress point for water leakage.

Minor Point #3

I also have to decide how I'm going to run the remote head extension cable from the radio to the remote head that houses the radio controls; it's a limited length cable (19.7 feet, or 6m), so some intelligent thought has to go into the issue. That might sound a lot, but it's likely got to negotiate some rather odd paths to get to the front of the wagon; in addition, I've already got cable for the dashcam running along the headlining to the top of the left of the windscreen, so that's got to be considered as well. Like I said, I've got some thinking to do!


I'm in two minds about MM 1&2; they both have strong points in favour of either method, so the jury's still out.

However, MP#2 will be the way I go for the antenna mounting. While I do like the idea of a water-tight seal as envisaged with the Motorola mounting system, it is not designed with the loading that would be imparted to it by the mass of the Comet CR-8900 quad-band antenna under wind or impact loadings; it is designed with smaller, sleeker, and infinitely more flexible PMR radio antennas (typically single whips with a small or no loading coils in the base).

The boot lip mounting system from Comet (their K-405 boot-lip mount, one of the units recommended for the CR-8900 antenna) is designed to take the loading that the antenna will exert on it; further, I don't need to drill holes in the body of the Discovery. It has the capability of accepting impact loading from two axes (X- and Y-), thus hopefully helping to preserve the antenna under tree strike conditions. SO, all things considered, it's going to be Minor Point #2 for mounting the antenna.

Now I have to make my mind up about which side of the wagon I mount the radio.

More on this sooner than later...

No comments: