Reyco 80/40 Meter Trap Dipole Dimensions

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Vince Bond:
I have a pair of new old stock Reyco 40 meter antenna traps which I will soon use to construct a 80/40 meter trap dipole. Trouble is, I can't find the printed directions that illustrate the dimensions and proper trap placement. I researched the Internet and the archives of this forum, but no luck.
      If I recall correctly, the smaller diameter end of the Reyco trap capacitor tubing is supposed to be connected to the wires leading to the center insulator and the larger diameter trap tubing should be connected to the wires leading to the end insulators. If anyone has the old Reyco antenna trap directions that came with their coils for any band, could they verify that for me?
     Also, the approximate dimensions I have been able to determine for this trap antenna call for the 40 meter wires to be about 32'9" in length, followed by the 75 meter wires, each of which are about 22'6" in length. Is that correct? If so, that yields an antenna of about 111', which sounds about right.
     Any confirmation of this information or correction would be greatly appreciated.

Vince K7NA

Alan Applegate:
Start here: http://www.unadilla.com/

Tim Cotton:
I have two different sets of instructions for the Unadilla/Reyco trap dipole  but neither seems to mention which end of the trap goes toward the center insulator.  I doubt that it matters much on a simple 80/40 installation.  The distance from the center of the center insulator insulator to the near end of the 40 meter trap is supposed to be 32 feet 7 inches at 7.175 Mhz.   The actual length will vary of course depending upon the frequency you're interested in, whether or not you're using an inverted vee configuration, the included angle, the height of the antenna above ground etc.  The outter wire (for 75/80 meters) is supposed to be 21 feet 5 inches at 3.875 Mhz and 24 feet 3 inches at 3.675 inches.  You can probably interpolate between or above and below these frequencie in terms of khz/inch etc. (~5.88khz/in.)

I suggest you adjust things for 40 meters first to get the antenna "happy" at the frequency of most interest and then (after you've got it where you want it for 40) to deliberately make the outter wires a bit long for the frequency you're interested in on 80 and prune judiciously until it's where you want it. 

I have one of these things in my attic about 15 feet above ground.  I feed it off center on 40M with a split of about 50 feet on one side and 16 feet on the other.  I did this because I wanted the coax to leave the antenna at a 90 degree angle in both the vertical and horizontal planes. .  The SWR on 40 is between 3 and 4:1 but the losses in a 50 foot piece of quality  coax at 7 Mhz are tolerable and my line tuner handles it with no problem.  I added about ten feet beyond the one 40 meter trap for one of the 80 meter wires and about 45 feet beyond the other trap.  The longer 80 meter wire is bent in about 100 different directions but the  SWR on 80 is about 1.80.

William W. Combs:
Vince,
Look here:
http://www.adurcomms.co.uk/pdf%20files/Unadilla%20traps.pdf

Bill, W8BC

:
From the center insulator to the trap is 32' from the trap to the end insulator is 22'

Mine ended up a bit shorter by the time I tuned it to the SSB portions of the bands, 104' overall - I put it up and down a few times.

Do a good job of connecting to the traps - I soldered pigtails with ring terminals for the final connections

80 runs a bit narrow but with a tuner you can do most of the SSB portion of the band.  40 is full band.

You tune the 40 meter section first, then tune the 80 meter ends.

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