Back in 2014, I made a carry-frame for my FT-857, ATU and battery from 15mm copper pipe – you can read about that on this page. During the summer of 2018, I thought about operating from the car “ninja style” where there may not be a lump of grass to push an angle-iron into or even a fence post. A drive-on base seemed like the ideal solution as I like to use “full size” aerials when /P.
The picture below shows the dry-assembly of my prototype – I decided to add further supports at the base of the “chimney” to ensure the mast/pole didn’t slip out.
The tall section holds my 10m fibreglass mast via a couple of bungee cords with the front wheel of my car sitting on the “8” section on the right-hand side. The inside of the pipe at that end is filled with potting-compound to keep the shape of the pipe when under load (from the car). When soldered, the frame is quite sturdy, but if using with metal (or thick GRP) poles, it’s advisable to add some guy-ropes to avoid any, ahem, unintentional horizontal polarisation.
I spent around £30 on copper materials: 3.5m of 15mm pipe plus various elbow and tee sections. I already had a blow-torch, flux and a roll of thick solder but did need a new can of black “all-purpose” spray paint. Commerical drive-on bases seem to vary between £35-65 so there is a good saving to be had if you wish to try this yourself and have the tools. I do enjoy making things – even more so when there’s fire involved.
As well as the 10m fishing-pole shown below, I also use it with some heavy-duty interlocking GRP poles when I have the VHF kit in the air. The fishing-pole is ideal for an HF Doublet and/or 2m Slim-Jim combo – and makes a great quick ‘n’ dirty /P setup when you find a quiet spot somewhere.