Hi. I own a 1975
Boler 13ft trailer that I am setting up for radio communications. I am a member of Niagara ARES in the Niagara Penninsula.
I have a bumper mount antenna support from DX Engineering, in the mount is a modified piece of ABS pipe. I insert an army surplus
fiberglass tent pole into the mount for a mast. The poles come in 5 ft lengths and I use up to 4 poles. On the top I put a Diamond X50 dual band antenna. The mount allows me to lay the mast down for assembly and then lift it into position. I also can use the same setup with a set of ham sticks for HF work.
I am also going to add small pipes onto the trailer frame to allow more
fiberglass masts around the trailer perimeter. The DX engineering mount is very expensive so just design your own, I had it from a different project and just reused it. The mount attaches to the bumper via a Princess Auto spare tire mount. The fiberglass poles came from Princess Auto as well.
If you have a roof vent on the trailer you could also change the vent lid to a metal lid and use a mag mount antenna.
Kevin VE3RRH