20 meters QRP Dipole

  • 20 meters qrp dipole
    20 meters qrp dipole

This is a portable dipole I built for 20 meters. It works great.

The SWR is really low. I would not recommend this for permanent use just because it is not build like a rock. It will do just fine for portable in the field operation. It is a great backpacking antenna. I only used 3 item to build this dipole.

Parts:

1. Film Canister
2. 36 feet of AGW 22 stranded wire. Cut it to 18ft for each leg.
3. However much of RG-58 you need with a BNC or PL-259.

 

Tools:

1. Soldering Iron with solder
2. Drill
3. Wire Strippers
4. Wire cutters

 

Directions:

I know how hard it is to read directions with no pictures. I have tried. I have made these directions very easy. It is fool proof. I have also included some pictures on the directions that are hard to picture in your mind.

1. Drill a hole through the bottom of the film canister to accommodate the RG-58; so it is SNUG. Make sure the hole is center.

2. Drill two holes on each side of the film canister. This is were the legs of the dipole will be inserted at. The holes should be no bigger than what is needed to fit the 22 gauge wire through.

3. Strip the coax. DO NOT cut off the braid. Untangle it and twist it so it looks like a wire. Make sure there is 1 inch of "wire" shield sticking out. Cut the dielectric down so there is about a 1/2 an inch. Then strip a VERY small potion of the dielectric so there is a very small amount of center conductor sticking out. Feed the coax through the film canister. Feed it from the bottom to the top. So the end of the coax is coming out the top.

4. Next, strip about 5 inches of the 18 ft long 22 AGW wire. Feed the end through the bottom hole; of the to holes on the side. Pull it through the top. Next find the middle of the bare section of the wire. Solder the shield to it. Just wrap the shield around the center once and solder. Cut off the access SHEILD not the 22 gauge wire.

5. Next, do the exact same thing as you did in step 4 but with the other dipole leg. And solder it to the center conductor not the shield "hi hi".

6. Ok, now do exactly as I say. I don't care where you start but pick one of the access wires one of the 22 gauge wires). There now should be two sticking out the top of the canister. In the middle of each stripped section there should be either a shield or center conductor soldered to them. Next this is kind of tricky. Take the bare end of the 22 gauge wire (the one that has the center conductor on it. Feed it through the hole above were to put it in. It is kind of hard cause the solder has made it stiff. Just try to feed it through so that out of one end there are "2" wires. One, the actually length of the leg. The other is the 2 inches of stripped wire. Make sure that both of those wires have some stripped sections that are closest to the canister. Look at the pic below.

7. Solder the small piece to the big piece. Look at the pic above you can figure out what I mean.

8. Do the same to the other side.

9. Now every thing should be inside the canister. Out the bottom of the canister there should be coax. Out the two sides there should be one wire on each side. Remember we soldered the two wires together on each side. Look at the pic below.

10. Now all that's left is cover the exposed bare, yet soldered wire on each side with electrical tape. Then for water proof ness you MUST fill the entire canister with Hot Glue or some kind of epoxy. I found that hot glue worked very well. Fill the canister almost to the top. Just so no more coax or wires are visible inside the canister.

11. String it up and cut it so length according to SWR. I found that trimming of about a middle fingers length at a time works. (About 4 inches). Just keep on trimming until the SWR becomes very low. I had to trim about 10 inches on each side to get perfect SWR.

 

That's it. Enjoy your new 20 meter dipole.

 

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