PAR End - fed SWL wire antenna vs MFJ version

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majoco

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Ridgescan said:
just be sure that you secure the PAR trans box mount sturdy enough to handle extra wire in wind and stuff pulling on it.

I would never do that, regardless of what the manufacturer said. Secure the near end of your wire to an insulator and then a wire or rope to the mast. Then make a short jumper wire from the antenna wire to the balun or whatever which is secured to the mast. If you are using an egg type insulator, loop the antenna wire and the support wire around the centre so that if the insulator does break , the wires are still joined together. If that's sounds confusing, I'll do a photo.
 

ridgescan

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Ridgescan said:


I would never do that, regardless of what the manufacturer said. Secure the near end of your wire to an insulator and then a wire or rope to the mast. Then make a short jumper wire from the antenna wire to the balun or whatever which is secured to the mast. If you are using an egg type insulator, loop the antenna wire and the support wire around the centre so that if the insulator does break , the wires are still joined together. If that's sounds confusing, I'll do a photo.
Mine's been up there 6 years so far and that darn #12 solid bare wire just won't snap! BUT, at the far end she's mounted to a solid aluminum mast that is quite springy, I keep the wire taught but not too much so, so there is a sort of "shock absorption" going on there and she's put up with some pretty nasty winter gusts up there.

Martin I have one more question for you if I may: will making my 45' counterpoise wire longer than 45' further improve upon its obvious current effectiveness as a counterpoise? I went and bought a 100' roll of #12 solid coated wire yesterday just to have more around in case, but am waiting for your thoughts on this first. Thanks buddy:)
 

WA8ZTZ

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My PAR has also been extended for better performance on AM BCB and LW. The wire used was 14 THHN solid. My experience with stranded
wire on receive antennas has been that they may eventually wick water and begin to corrode between the strands. The corrosion causes the antenna to get noisy and also produce mixing products.
The PAR EF-SWL has served me well for a number of years. It is my main antenna for SWLing LW through HF.
 

ridgescan

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My PAR has also been extended for better performance on AM BCB and LW. The wire used was 14 THHN solid. My experience with stranded
wire on receive antennas has been that they may eventually wick water and begin to corrode between the strands. The corrosion causes the antenna to get noisy and also produce mixing products.
The PAR EF-SWL has served me well for a number of years. It is my main antenna for SWLing LW through HF.
Years ago before I settled on the #12 bare wire I have had a long time now, I ran #12 stranded, coated wire and I too noted a considerable element of "white noise" in there that I figured was the plastic wire coating building up static along the line. This is why I've been using the bare copper all these years. I'm sure my guess about the coating was wrong and your post is accurate but I had no idea.
The new counterpoise I'm running now is 45' of that very stranded line I took down and put away then.
I am going to replace that counterpoise soon with the #12 solid I just bought the other day just for good measure.
 

ridgescan

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This is the radio shack wire I’ve had for years but never used it. Collecting dust in my tool box.
https://www.amazon.com/Radio-Shack-Shortwave-Antenna-Kit/dp/B000UBROV2
Will this wire work for an extension?
You mean an extension to the new PAR wire you'll be getting? No. PAR seals that flex wire and it has a little sealed loop at the far end for accepting an insulator mount. Plus you really don't want a sloppy tie-up in the middle of your receiving wire you want it smooth and un-interrupted. I say it's best to go blow about $30 on 100' of nice solid copper wire and run it by itself off the PAR box and stow away the 44' PAR wire for later stuff if you intend to run a longer wire.
 

WA8ZTZ

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Years ago before I settled on the #12 bare wire I have had a long time now, I ran #12 stranded, coated wire and I too noted a considerable element of "white noise" in there that I figured was the plastic wire coating building up static along the line. This is why I've been using the bare copper all these years. I'm sure my guess about the coating was wrong and your post is accurate but I had no idea.
The new counterpoise I'm running now is 45' of that very stranded line I took down and put away then.
I am going to replace that counterpoise soon with the #12 solid I just bought the other day just for good measure.

My choice of THHN insulated wire was due to it being readily available. The important thing being the fact that it is of the solid variety and not stranded.
As to whether the solid wire should or should not be insulated, it probably doesn't matter too much for a simple SWL antenna. However, military and commercial aircraft wire antennas (ADF sense antenna, HF, Loran A) use steel (for strength) with a rather thick plastic insulation. My understanding is that the insulation serves to prevent precipitation static being heard in the radios.
 

majoco

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This is pretty close to what I was taught over 50 years ago on how to make wire antennas for ships although the wire was not insulated - hard drawn copper 7 strands and we had to make joints without solder or crimps. There's also a little sketch of a wire antenna which indicates that the actual final termination to the insulator has no strain on it other than that short piece of wire. There's also a pic of a corner of my delta loop - the fat wire goes up the the mast and the thin yellow wire goes along the fence top. Both wire go through the insulator and are bared and twisted tightly together then soldered and sleeved with heat-shrink tubing - I don't mind soldering on a joint that's not strained but it's a no-no on any of the wire joints that are under tension and get movement from the wind or anything like that . The solder 'wicks' down the strands and becomes a flex point which will eventually break where it changes from solid solder to the stranded copper.

WP4AOH: Dipole Antenna Construction Ideas
 

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bearcatrp

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You mean an extension to the new PAR wire you'll be getting? No. PAR seals that flex wire and it has a little sealed loop at the far end for accepting an insulator mount. Plus you really don't want a sloppy tie-up in the middle of your receiving wire you want it smooth and un-interrupted. I say it's best to go blow about $30 on 100' of nice solid copper wire and run it by itself off the PAR box and stow away the 44' PAR wire for later stuff if you intend to run a longer wire.
I'll try the Par wire first before deciding on anything else. Thanks for the pics. Food for thought.
 

bearcatrp

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Anyone know where I can order the Par End Fed SWL? Ordered from universal radio last wednesday. Nothing on their web site showed back ordered. Finally contacted them today asking about my order and was told its on back order. Should be a law to make online retailers show in stock or not. They lost my business. I emailed LNR precision to see if they have one in stock. I see fleebay has some but don't want to take the chance on getting a Chinese knock off.
 

ridgescan

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Anyone know where I can order the Par End Fed SWL? Ordered from universal radio last wednesday. Nothing on their web site showed back ordered. Finally contacted them today asking about my order and was told its on back order. Should be a law to make online retailers show in stock or not. They lost my business. I emailed LNR precision to see if they have one in stock. I see fleebay has some but don't want to take the chance on getting a Chinese knock off.
I did a search and it's a tough one:( it seems the EF-SWL can only be produced so fast and can only be bought at LNR Precision, Universal, and used far as I could see.
 

bearcatrp

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Got it up, not the best though. Will do until I order another cable next month. Sure picks up allot more noise than my super antenna. Tonight will tell the tale though.
 

W5lz

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Any conductor can be used as an antenna. If it will conduct electricity then it -can- be an antenna. Length of that wire also plays a part. That length is in relation to the wave length of the frequency being listened to. "Tuned" lengths, having a 'special' relationship to the wave length of the desired frequency is a nice thing to have. The 'bad' part of that is that the length changes with frequency, meaning that it may or may not be particularly conducive to hearing stuff on some other frequency. All that means is that reception may be less than 'optimum'. That isn't a 'killer' in it's self, I don't think I've ever had an 'optimum/perfect' antenna and haven't missed much. (This says nothing about impedance matching, or propagation! That impedance matching isn't that big of a deal to most receivers, propagation is!)
Different antenna 'styles'/shapes have different reception characteristics. Those characteristics can usually be changed/improved by simply moving the antenna, 'pointing' it in different directions, getting the thing higher, maybe changing your socks?
What all this amounts to is that no single antenna is the 'best' in the world. No matter what the advertisements say...
 
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