Sectional Dipole for the "Go-Kit"

The main antenna consists of the two loops on top, the two below are the 60m sections that can be added.

I know I am not the first person to come up with this idea. I have seen and heard of many variations of this antenna throught my years being a Ham radio operator. One of them even included relays for remote band control HI. Mine isn't that sophisticated, in fact it is as bare-bones as you get.

I wanted an antenna that I could toss in my go-kit so I would never be without an antenna. My requirements for it were to be coax fed, compact, cover all bands 6-60m, and be resonance agile so I wouldn't be stuck cutting or needing to add to it when out in the field.

The first step to the antenna was getting my lengths. I used the formula 234/f (in mHz), or 1/4wl. This gave me the length I needed for each piece. I started with 6 meters and added, sequentially, the other bands to that one after the other all the way to 60 meters. The only hangup I had was on 12 meters. The length I needed turned out to be 4" longer than what I calculated for some reason. After that the rest of the lengths were close. As I got lower in frequency I had to trim more and more. It is better to be long than short on this one.

I seem to remember that insulated wire (not shielded, just regular coated wire) has a higher velocity factor than bare wire. This means that the length needed will be shorter than in theory. Case in point, I chopped off a good foot to 16" off my 40m dipole when I made it out of 12g stranded hookup wire (the suff you get off the spool in a variety of colors at Lowes or Home Depot). I am not sure what the exact conversion is for the 24g wire I used, however.

Another thing I did with this antenna is I made jumpers that varied in length so I could tune the antenna by making it longer or shorter. Depending on where the antenna is set up the SWR could vary a little so I wanted to be on the safe side and design this in to the antenna. All the bands are tuned with a 4" jumper in place. Since I started with 6 meters this is really the only band that is "short". This way, if the antenna's resonance goes down in frequency I can pull out the 4" jumper and add a 1", 2", or both a 1" and 2", or none at all, to get the antenna tuned back where it should be. I have extra jumpers to go all the way up to 16" extra if need be on the high side.

I did not make a jumper for 75/80m. The antenna is very long as it is at 60m and the wire is so small that I didn't want the extra stress. For a portable antenna it might not be too bad, though.

I used LMR-200 for the feedline. I was going to use LMR-100 but I figured the 200 had less loss, which is a big consideration if QRP is necessary. At 5 watts you need all the efficiency you can get. I figured 35' of feed line would be enough to go up my crappie pole and over to the rig with plenty of room.

The wire I used for the dipole was a spool of 75' of 24 guage speaker wire from Radio Shack. I didn't realize it until I started working on the antenna that the wire is solid. This isn't the best stuff to use for an antenna as it breaks easier than stranded wire (stranded can flex more without the same metal fatigue).

I used 12-14g spade lugs from Home Depot. My first thought was to crimp and solder them. However, only the female ones took solder. The male ones must have some kind of coating on them that won't allow the solder to wet to it. Instead of soldering them I folded the speaker wire over (about 3/8") and stuck the loop in to the connector and then crimped it. This way the wire has a better hold in the connector. One thing to keep in mind is to get the connector crimp "fold" to go in between the loop. In otherwords, the wire isn't all on one side. This will make it impossible for the wire to come out without breaking.

The antenna works very well. However, I have noticed the bandwidth on the lower bands to be quite narrow. I would attribute this to the wire being so small. I am sure this is a common problem. I have the antenna tuned on 40m so the SWR dip is about 7.100. This way, the SWR goes to about 1.5:1 at the bottom of the band (where I will operate mostly anyway - CW) and I can still get up in to the SSB portion with a 2:1. Since I am an Extra I can play on the bottom of the SSB band, which the SWR is only 1.3-1.5:1 there. The bandwidth on 60m doesnt matter since the channels only span about 70-80kHz.

Due to my "unexpected weekend" I was unable to get any pictures of it deployed this time around. My crappie pole broke Sunday morning so it is out of commission for a while. I will wrap some fiberglass around the break and fix it up when I get some time.