Threw up my first wire antenna

[DennisCA]

I decided to throw one up despite it not being the best conditions outside yet. It's march and everything is still frozen and under a meter of snow, so that makes it impossible for me to get at the ground and drive down an earthing rod for my receiver. But I wanted to try it and I got free time right now. I want to receive LW, MW and SW radio with this.

Antenna is connected with a rope to the house, insulators are made from two zip ties. The antenna wire itself is mig-wire .8mm. Soldered a wire to the end and ran it through the window to the receiver.

The other end is attached to a tree, I think it's about 3 meters high and 15-16 meters long. Next to my shed (currently under construction).

It's not performing as well as I had hoped. There are no domestic SW or MW/LW transmissions so I can only listen at night to far away stations. I pick up some clearly, I think it works better with the SW band than the 520-1600khz band. I think a longer antenna would be better for those frequencies?

My receiver has old style connectors and not coax (only FM with coax) so I have not given any thought to coax or transformers at this stage. Though I believe a coax cable to the receiver, which I believe would require another transformer at the receiver, could help with picking up noise from modern equipment.

I would like things to thaw because I really want to see for myself if a ground will cut down noise and improve reception. Another thing I am wondering about is the roofs on all my buildings (three total) is sheet metal, I wonder if they can create shadows. Maybe I need to get my antenna above the roof lines? I got a 4 meter mast in the shed which I am planning to mount on my house this summer and fit an FM antenna which should then be like 8 meters up.

Perhaps it could also be a good mount point for a long wire antenna? I could get a 30 meter wire from there to the backside of the shed, but it might be a bad idea since the metal roof would be underneath and I read in an old radio amateur magazine (1924!) that wire antennas should not lie above metal roofs or it will be the same as the antenna saw a lot lower.

I also wonder if I could run the antenna in an L-shape, that way I could get 50 meters or 160 feet. Or maybe a dipole setup going in two directions from the house?

 

[popnokick]

A very successful and well-regarded End-Fed shortwave listening antenna is the Par EF-SWL. Details are here -
https://parelectronics.com/swl-end.php
A couple of major differences between the Par EF-SWL and what you put up are -
- The Par antenna is 45 feet (14M)
- The Par has a 9 to 1 balun / unun
Incorporating both of the above into your end-fed longwire is likely to improve the performance considerably. The metal roofs / buildings horizontally adjacent to the antenna are not likely to be a problem, but you are correct in not having the wire element directly above a metal roof.

 

[DennisCA]

You mean I should shorten my wire by 1-2 meters, won't that be worse? I live in an area where I only can pick up weak signals from far away, so I am interested in making the best possible receiving antenna I could make. I do have a decent amount of space to put up a longer antenna.

If I add a balun or unun, I guess I need another one by the receiver to convert it back since the receiver is a vintage unit which uses the old fashioned connector style.

 

[popnokick]

A feed-line choke in addition to the balun would be appropriate. This is better described and illustrated here -
https://palomar-engineers.com/tech-support/tech-topics/best-hf-end-fed-antenna
The 1-2 meter difference in wire length between what you have installed and what the Par is using is likely insignificant for receive-only operation.
Finally - What is your receiver make / type? If we know that we can make suggestions regarding adapting the coaxial lead-in to the receiver. At a minimum, you'll want to connect the center conductor of the coax to the antenna input. But you may also want to use a clip lead jumper from the coax shield to the radio chassis or other common ground point. Then you can attach / remove the outer shield of the coax to determine which results in better SNR for a given band & signal.
You may also want to consider a preselector such as this
https://mfjenterprises.com/products/mfj-956
or the MFJ-959C that includes a preamplifier -
https://mfjenterprises.com/products/mfj-959c
I would start out with the balun and choke to see what happens and add other components if you feel the need.

 

[DennisCA]

For now I am just using a portable radio for SW and a Philips F5110 for MW/LW but I have purchased a Telefunken Concertino 3520 receiver that will replace both of these units. It's 70s vintage equipment.

Would an increase to 30 or 50 meters make a difference, as well an increase of height?

 

[FLPage]

Threw up my first wire antenna

Bet that was painful!

 

[popnokick]

There are several threads here on RR addressing the "how long / how high" question. They can be found using Search. Here is but one of them - Should I add more "antenna" length for better SWL?

 

[pnw73]

Threw up my first wire antenna

Bet that was painful!

I remember many years ago when I did mine. It was nearly endless.

 

[Mophead]

Good job! Some folks are good with bow and arrows to shoot weights and pulleys over those branches. You wont get too far until that white crap melts. Good luck!
P.S. I have been on my roof a few times in the past when it was covered in snow just to adjust my CB antenna's SWR lol.

 

[TexTAC]

Soldered a wire to the end and ran it through the window to the receiver.

What type of wire and connector did you use to connect the antenna to your radio? Your antenna should work pretty well on AM band reception. I have a 66 foot dipole I use for HF transmissions but also use it for AM reception and it works really well.

 

[majoco]

Is Mig wire a good conductor?

 

[DennisCA]

It's copper coated steel and I've read a lot of people use steel wire and that there's also a type of stranded wire which is copper coated that is very popular for this purpose. So I thought I would give it a try since I had a spool I wasn't using. I also saw someone on youtube make a three wire antenna with it and get good results.

TexTac it's just speaker wire that I've plugged right into the socket.

 

[DennisCA]

Good job! Some folks are good with bow and arrows to shoot weights and pulleys over those branches. You wont get too far until that white crap melts. Good luck!
P.S. I have been on my roof a few times in the past when it was covered in snow just to adjust my CB antenna's SWR lol.

Thanks I used a big bearing and I just swung the rope around and loosed it. I was thinking a sling shot would get me higher though. I was thinking of trying to get the other end higher up and see what it did.

I have a roll of 50m stranded wire I wanted to put up later, I am not sure it is copper or not. It's signal wire for robot lawnmowers that's meant to be buried underground. I have actually nearly 400 meters of that buried under ground to encircle my yard. I was wondering if that could possibly work as an antenna, but since it's underground I doubt it.

 

[DennisCA]

By the way, this is a question I can't seem to find an answer for despite long searching. But if I use a 9:1 unun and run a coax line into the house. Do I need a reverse 1:9 unun at the receiver to make it compatible with my bare wire style connectors?

I am also checking out commercial ununs and they often specify a frequency range like 1.8mhz and up, which to me sounds like they would not work, I want to listen from150 khz (longwave) up to 15-16mhz. But it seems like it's just a transformer, shouldn't it work with any frequency?

What the actual connection on my receiver looks like. No coax except for FM here.

 

[mass-man]

No balun at the receiver...the 9:1 device brings the basic impedance of the wire down 9 times to closer match the 50-75 ohm input of the receiver.
Can’t tell what the input jack is, with the plug in there😱. But guessing it’s an RCA phono plug...easy to use, to solder or adapt if you want!!!
Height is might when it comes to antennas...from experience 50/75 ft of wire will work well! But 20ft off the ground, meh...50ft WOWZER!
The ground rod might help noise, might not! Another one of those try it and decide...

 

[DennisCA]

Ignore the plug in the center, that is FM 75 ohms and is a coax socket.

It's the two small holes to the left Ant and Gnd that for AM, on the right are two similar holes for FM 300 ohms. Presumably these old receivers expect something in that range on the non-coax inputs.

 

[bearcatrp]

I used a fishing rod with a heavy line and sinker to cast over the trees. Then cut the line and tie it to the wire to bring it over the tree. If you have a drone, that will work also.

 

[DennisCA]

I suppose I can just try making a pair of 9:1s and see what happens.

 

[DennisCA]

I tossed the other end of the antenna up into another three. I got it maybe a little higher. I need a better way to get it higher up. But I feel I am getting better reception now. Getting some english language stuff from china at the moment. Sun is still up.

 

[popnokick]

I need a better way to get it higher up.

There is a device made by Bill KR4LO called the "Air Boss". It is an air-powered antenna shooter for throwing lines into the air over trees, houses, etc. I have one and they work great for getting antennas up into trees. And unlike arrows and slingshots, the fishing weight sinker it throws does not get snagged in branches when it comes back down the tree. Watch the demo video here -

Unfortunately, I just tried the website for the Air Boss and it appears to be down (or has changed).