Many bicycle tours, many antennas tried . . . 

 

Over the years (many of them) I've combined two loves: bicycle touring and QRP hamming. For the hamming part, I've been concerned with mainly two things: keeping the weight down and antennas that worked well and were easily to erect and pack away. Most of the experimentation over the years has been with antennas, and I've finally settled on one that really performs. But I want to list the various ones and rate them.

 

First of all, every year I take a least a week and go on a loaded bicycle tour. That means I take tent, sleeping bag, cooking gear, food, and all the little things that make a trip self-sustaining. I'm usually the trip organizer, and I take others along. From time to time, another ham joins the bunch. I gradually developed an affinity for touring in mountainous areas, and even developed and wrote the guidebook for a route called the Pacific Crest Bicycle Trail (for more on it, see Wikipedia). I've also been touring along another route called the Great Divide Route. Both routes go from Canada to Mexico. The gear I take, with the ham gear included, usually adds between 50 and 60 pounds to the bicycle. These trips are a great way to lose weight!

 

As for the antennas, I want to start at the very beginning. The first one I used, back when I was using a simple Oak Hills Research CW transceiver, was an all-wire ground plane antenna, good for one band (probably 20 meters). It had four radials that sloped down toward the ground. Tell the truth, I really never had much luck with it. Part of the problem was that I never had it high enough above the ground. 

 

Another experiment was with a "slinky" (child's toy of expandable metal coils) antenna in the woods, configured as a dipole in an inverted V position. I used lengths of cord inside the slinkies to support them and help them hold their shape. I forget what band the antenna was built for, but I was quite disappointed in its performance. 

 

In terms of physical deployment, I had the worst problem with a fan dipole. It had three different lengths of wire on each side of the feed point, to enable operating on three different bands without a tuner. In terms of hanging it up and keeping the total of six lengths of wire from becoming entanged with each other, well ... let's just say it merited a bunch of increasingly unpolite cuss words. I wasn't impressed with its performance.

 

Somewhere about this time I began using NorCal QRP club radios (now Wilderness Radio). I began to have the ability to use both CW and SSB.  I began taking solar panels along to charge my battery.

 

An antenna that worked better than the previous ones was an inverted V dipole with electrically expandable sides. Built into its arms were alligator clips which allowed me to connect additional lengths of wire to the feed point to operate on the lower bands (the wires were already "built in" to the antenna's arms -- they just needed to be electrically connected). There were two connector points on each side, enabling the antenna to operate on 20, 30 or 40 meters. Results were good, but having to lower the antenna to change the connections was a hassle, especially at night. 

 

Next was an antenna good enough that I used it over maybe a three-year, three-trip span. It is a variant of the G5RV antenna. I found out about it in one of the ARRL Antenna Compendiums (I think I own all of them) where it was called the Suburban Multibander. It's about 96 feet long with a specified length of 450-ohm feed line, and I still use it as a horizontal dipole at my home QTH, about 30-35 feet up. But in the field I used it as an inverted V, again. It is self-resonant, as I recall, on 20 meters, but on the other bands requires an antenna tuner (antenna matching device). I was proud to develop an evolved way of packing it up: while rolling it all up, I was able to wrap up the thin wire used for the arms within the coils of ladder line, so that it became one big, compact coil, all held together with electrical tape. The major deficiency of this system was that it took too long to deploy and too long to pack up. I still remember several times when I was still packing up my antenna while the other bicyclists patiently waited, ready to hit the road. Eventually I found ways to deploy this antenna without any help, but having another person to assist was handy.

 

This leads up to the antenna I'm using today. On several tours a ham from Germany, Gottfried Kloyer DL2MFJ, joined us and operated very successfully using a QRP CW rig and a simple vertical wire antenna. Eventually I got around to finding out more about the antenna. It was a half wavelength vertical (I forget which band he had it cut for) and was tuned with a custom tuner built into a plastic photographic film canister (contining only a wound toroid and a variable cap). Eventually I got the specs for it and built one. The tuner is fed with simple RG-174 coax for light weight, and it performed really well. Instead of having it perfectly vertical you angle the bottom slightly toward the direction you want the maximum signal to go. If you can't make this antenna vertical, it's also possible to throw it around in a bunch of configurations including the upside-down L position. Not content to have a monobander vertical, I've developed a version that's in a way similar to my alligator-clip-expandable antenna, above. It can be made into half-wave antennas for 20, 30 or 40 meters. The tuner has three selectable toroids inside, and a wide-range variable capacitor. The deficiency, of course, is that I have to lower the antenna to change bands, but only having to make or remove connections on one wire is much easier than with two wires. One of the wonders of this antenna is that it requires no radials or so-called counterpoise wires. The tuner can be pretty close to ground level.  I have used chalk-line reels to stow the wire. In the latest version of the antenna, I used a spring-loaded clothesline reel to stow the wire (it's a bit heavy, but convenient). With this antenna, DX has been possible. It's not always possible to find a high-enough tree to support a 40-meter half-wave vertical (it would need to be at least 60 feet up) and shoot a line up that high.  

 

These days I've been using a Yaesu FT-817 transceiver and NiMH battery.

 

Below is a photo of me operating from a tent during our 2006 tour through the Siskiyou Mountains of Northern California, at about the 8,000-foot level, using the last-mentioned antenna.  

 

 

-- Bil Paul   KD6JUI (ex-W9KSJ)   San Mateo, CA

 

 

 

 

Many Bicycle Tours

 

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