THE KD4WPC 6 METER SUPER SCANNER MODIFICATION
I just made my first contact on 6 meters using a
converted Super Scanner CB antenna element modification...EZ to make!
What was that....you don't have an old Super Scanner laying around, then checkout the #2 project below....read on anyway and learn how to make a duel polarity 6 meter antenna on one support or if you have it, use the old Super Scanner antenna!
#1. The Super Scanner
For the Super Scanner modification to 6 meters, I
pulled the end tube sections from both ends of one of the dipoles leaving 57 inches on each half of
the dipole and did not change anything else...I
drilled a hole in the bracket close to the feed points and bolted on an
SO-239. I soldered a piece of solid copper wire to the center of the
SO-239 and tied it in to the insulated driven side. I didnt measure it...I
just used a piece long enuff to be able to put my finger between it and
the bracket and cut what tail I had... A ground strap is not needed as the
SO-239 bolts right to the bracket.
The swr is flat over the entire band. I'm in
Stringtown OK, and talked to W3IH in Truth or Consequences NM for my first
contact on this dipole.
I've made a second one to add to the Super Scanner
boom for vertical polarity as shown above. Again...flat swr over the
entire band with 50 watts. If you use a switch to go from horizontal to
vertical, it should work fine.
If you have a set of Super Scanner antennas laying
around, give them new life...make 6 meter dipoles out of them.
#2. Dual polarity 6 meter antenna without the Super
In the project for the dual polarity dipoles, drawing above, you will see that you simply mount one dipole vertically and the other horizontally and both are insulated from the boom and supported by it. This gives you dual polarity dipoles.The boom distance between the dipoles should be about 1/2 wave length apart or further, but not critical. You will have to fabricate the end of boom insulator and mount for each dipole as needed by your abilities and materials on hand.
Each dipole's length is the same as the Super Scanner antenna above using aluminum tubing of the same or similar size, average size of about 5/8th inch in diameter (original Super Scanner elements are tapered), 114 inches total or 57 inches per half and the boom length should be at least the total length of one dipole end to end. Some tuning for lowest swr may be needed so start long and trim down for lowest swr.
Feed each with direct 50 ohm feed. A small rf choke
can be used on each if needed to help keep rf off the feedline and help
maintain the antenna pattern. Use about 6 turns of coax on a 4 to 6
inch PVC form at the end of the feedline next to and connected to the
dipole and connect the opposite end as usual to the feedpoints.
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