[This is an updated version of a post that appears on my old website. – WB3GCK]
I do quite a bit of my QRP operating from portable locations. I like to use simple wire antennas but, truth be told, I really dislike spending my limited operating time trying to get antenna wires up into trees. Also, when activating parks for Parks on the Air (POTA), I often operate from the cab of my truck and need an antenna that is self-contained and quick to deploy. This set up fits the bill.
What I did was modify my homebrew roll-on mast support so I could use my hitch-mounted bicycle rack to support it. This only required the drilling of two holes in the roll-on mount. Figure 1 shows the roll-on mount clamped into the bike rack. In this case, I was supporting a 31-foot Jackite pole. After extending the pole and removing the bottom cap, I just lower the pole onto the 1-1/4 inch pipe. That’s all there is to it.
By selecting the right size of pipe, I can use this technique to support a variety of masts. For example, I’ve used this type of mount to support two 5-foot sections of TV antenna mast. I used this configuration to support a 1.2 GHz yagi for DStar digital communications during an ARES-RACES drill years back.
When operating QRP-portable, I often use a vertical antenna made from a 30-foot piece of hook-up wire and fed through a homebrew 9:1 unun with an 18-foot length of RG-8x coax. The unun is just attached to the 31-foot Jackite pole using some small bungee cords. No radials are used, which gives this set-up virtually a zero footprint. You can find more information on this configuration on the EARCHI website. I’ve successfully used this antenna in the field over the past few years. It’s a bit of a compromise, as antennas go, but it has always served me well. The extra height using the bike rack mount seems to help performance a bit. (Although I can’t quantify that, I’m sure the extra height doesn’t hurt.) With the internal antenna tuner in my KX3, I can work all bands from 40 through 10 meters. Heck, I’ve even used it on 80 meters a bunch of times.
I used this particular antenna configuration countless times in recent years. It was my “go to” antenna for NPOTA activations. Within 5 minutes of arrival, I can be on the air. When it’s time to leave, tear down is just as fast. Now, that’s what I’m talkin’ about!
73, Craig WB3GCK