Im going to get cracking with this. I have a 10m fibreglass telescopic pole (a windjammer), for which i have already worked out a neat guying system using bungy cords, and have created a radial plate for it.
The proposed design is a top-center loaded vertical. The coil will be positioned 8 ft from the top, allowing that bit extra wire for capacity. Calculations show this should be about 55% efficient. Combined with my MKARS-80 giving 3-5w, this should let me have an erp of about 2w. Not great, but the real benefit is expedience - i can get this rigged at a portable site/summit in about 5mins
Im also considering a linear loaded coil vertical. But winding the coil every time i put the pole up would be slow, tedious and inaccurate. I wonder what a slinky streched over 30ft will resonate at???