End-fed, Inverted "V" for 17-20-30-40 Meters
Four Band Lightweight Antenna
made 08-05-2006

Here is a 4-band antenna that rolls up into an small Grundig antenna case. I pulled out the original wire and replaced it with 67 feet of 28-ga. Teflon-coated wire. It is a full halfwave end fed inverted V for four bands. I designed it to be backpackable and uses the PVC support base I made earlier. The base and mast break down to no more than 16" lengths, and as you can see, the antenna itself takes up little space. There are different lengths for each band, and all sections screw together. The banana plug plugs into a homebrew L-C tuner at one end of the antenna.


grundig.jpg
There are four antennas in here!

Here is a crude diagram showing how I have arranged the different bands. The blue rectangles are the feed points. Note: I don't actually set up everything as seen here. Either the 40 is up, or the 17-20-30 wire - not both at the same time. For 17, 20 and 30 meters I set up at the inner feedpoint. The 17 meter antenna is mostly a 1/2-wave sloper with an extra 3 feet going down the other side. On 20 it is much the same, just more wire on the side opposite the feedpoint. Only 30 and 40 meters are fully symetrical Vees, but all wires are a full 1/2-wave for the given band. If I am on 17, for example, a thin guy rope supports the three feet of wire on the right and substitutes for the missing 20 m and 30 m wires.The 40 antenna is simply ALL of the separate wires screwed together. To tune I use my homebrew matching unit.
layout.jpg


The photo below shows the barrel connectors I used for changing bands. They come with swivel loops, but I removed them and soldered the 28-ga. wire into the hole left by the loop. They are only about 3/8" long, and quite interesting to work with (small and slippery with tapered ends). Here is a picture showing the connector - with the loops removed - and with wires soldered on.

barrel.jpg
barrel connectors used for jewelry making

To support the center of the antenna, I remove the tip section of the 14' Cabelas graphite pole because it is just too flimsy. A plastic screw anchor holds the wire in place. The anchor is split halfway down, and the antenna wire slides into it.

center.jpg
dipole center

Below  is a photo of the mast and base set up. I have added two more 16" vertical sections to the original design. Because the 1/2" PVC is not quite sturdy enough to support this much height, I used some light string as guys. Now it's very stable, even with the 40-meter wire draped over it.


newmast.jpg
mast height is 19' 2" overall

The setup is a bit unconventional and has yet to be tried except with the MFJ analyzer where I was able to get a 1.0:1 match on all bands. It is a bit low for 30 and 40 meters, but I wanted a compact, self-supporting antenna system good on multiple bands for treeless hikes and campouts. I could have added 10, 12 and 15 meters, but mostly wanted to see if I could cram a 40 meter antenna into that small Grundig case including all the barrel connectors, and three more connectors might not have fit.

I hope to test the antenna on all four bands soon.

Jake,  NØLX








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