My Hustler 4BTV has served me well. It is an extremely rugged 4 band trapped vertical (40m, 20m,15m, 10m) and mine has been up now for about 7 years.  It would be nice if it was updated to cover WARC bands, and indeed there are add-on kits for 30m, 17m and 12m available but they range in price from about $50 to $100 per WARC band.

A few years ago I stumbled upon a URL that offered a do-it-yourself option for adding 17m and/or 12m to the 4BTV or other trapped vertical by paralleling a quarter wave wire for the additional band, and spacing it about 6 inches away from the vertical.  I kept reminding myself that the next time I took the 4BTV down to do some maintenance I would give it a try.  As it turns out, we ended up being in town for the Labour Day weekend and I decided that it was time to replace the guys on the antenna and adjust the 20m resonance point  (a bit too low on this band) so I quickly cobbled something together using a couple stainless steel hose clamps, a scrape piece of PVC pipe and a 13ft length of #26 AWG teflon coated, silver plated wire.  I added my own twist to the implementation by drilling a couple of extra holes in the piece of PVC pipe to implement a scheme to keep the wire taut without putting strain on the point where the wire is connected to the radiating element of the antenna. I am using a short piece of small diameter shock-cord to provide tension.

Given that I had all of the materials on hand, this was essentially a free modification and it gives me access to one of my favourite QRP DX bands.

Below  are a few pictures of the finished product. The end result is a 1.3:1 SWR across the 17m band.