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Rfman100
Posted on Saturday, September 13, 2003 - 11:46 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I want to improve the reception to my SonyICF2010. -Which has an atenna hole on the side.

Since I do not have the space to run a long wire. (I think it's the type that has 40 or 20 feet on both sides and they are connected in the middle with a wire that runs to the radio.)


My idea is to make a coil in the shape of a T. By using PVC tubing. However, since the wire is wrapping around the tube, how close can the wire be to each other in the turn?

And must the wire be sheid?

Thank you.
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Ca346
Posted on Saturday, September 13, 2003 - 4:15 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Take a look at "www.ccrane.com" They have some great antenna's and their catalog has some great idea's.

I have a Drake Model SW1. I have found the best antenna for me is a single very thin wire using electric hot wire for horse and cattle fence. (It's very cheap $:):)) The higher you can get the wire the better the DX is going to be. You could probably say that about all antenna's?

Don't worry about the wire in the turn, just make sure you keep it away from electrical outlets/wires, etc. You'll pick up alot of noise.
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Bruce
Posted on Saturday, September 13, 2003 - 8:49 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

and a small antenna tuner like the mfj-945 helps too
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Scrapiron63
Posted on Sunday, September 14, 2003 - 8:44 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

The tuner will really help, my old 50 year old Hallicrafters SX-99 has a build in tuner, it will really make a difference from one band to the next. I use one of my guy wires on my tower for an antenna. Its insulated on each end, the top is about 70 feet in the air, and it being on about a 45 degree angle gets both horz and vert signals. Hard to beat that sound you get from those old tubes. scrapiron
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Rfman100
Posted on Sunday, September 14, 2003 - 1:14 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Thanks for the CCrane website, I know about it from Art Bell.

But I want to try and make my own coil antenna in a T shape. I just need instructions in building it. Mainly how many feet on each side. Then I have to figure out how thick the PVC should be. And what kind of wire and should it be shield.

Then from the feed line (I think thats what is called.) should the line go into a device before connecting to the radio.

BTW: My favorite SW station is WBQC 7415 MHZ.
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Ca346
Posted on Sunday, September 14, 2003 - 6:56 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I never thought about using one of the guy wires on my tower... I forget now what length they are insulated at, but I think it is every 7 or 9 feet, making them way too short for SW. But the info from Signal Engineering (I have a Lightning 4+) said to ensure the top 25 ft or so of guy wires below the Quad was shorter guy wire so no interference.

But you got me thinking..... A 100 ft wire from the tower to the tree way back there...
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Mr_Rf
Posted on Sunday, September 14, 2003 - 10:10 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Most ARRL handbooks and ARRL antenna books have articles on making small loop antennas using PVC or other similar materials. If you don't have either check out your local library. Also some good net links:

http://www.antennex.com/preview/myloop.htm
http://www.qsl.net/vu2wap/antenna/projects.html
http://www.arrl.org/htdig/?method=and&words=loop

And, to echo the other posts, matching the antenna means everything! Use a tuner even on receive.

Happy antenna making, it's my favorite way to kill a day!
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Rfman100
Posted on Sunday, September 14, 2003 - 11:46 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I didn't know that even having a reciving radio such as a Shortwave you had to check your SWR. I thought that was only for RX radios?
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Kc0gxz
Posted on Monday, September 15, 2003 - 4:32 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Rfman100

No. You do not have to "check" your SWR, which would be pretty difficult to do with a receiver.

What Bruce and Mr_Rf are talking about is when you use a tuner on a receiving antenna, you are actually tuning the antenna to the band and frequency. You're bringing your antenna into frequency resonance. You will hear the difference in your receiver as you tune closer to the frequency because signals will be heard stronger.

Also, a preamp that will cover 180-10 meters will also be of great use to you. I have a couple of them and wouldn't dream of parting with either of them.

Whatever antenna you buy or make, just make sure it's outside somwhere.

Jeff, kc0gxz.
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Rfman100
Posted on Wednesday, September 17, 2003 - 11:37 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Another problem with my Sony shortwave. I mis-place the instruction booklet somewhere at my my house. When I switch to USB or LSB the signal drops down to almost nothing. Funny, because the opposite happens on the CB!

My dream shortwave to buy is the GRUNDIG SATELLIT 800 Millennium.

I do know there are ever more exspenive SW radios, but I do not have that kind of money.

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