Home |
Search |
Today's Posts |
|
#1
![]() |
|||
|
|||
![]() "MC" wrote in message ... I'm picking up AFN on their Puerto Rico freq. of 7.507Mhz. Now this may not seem a remarkable thing but I am in the South East of the UK. Again not remarkable but being new to this Shortwave stuff, I have no idea what I have done to enable me to pick up this station. Yesterday I purchased some common "household" wire (not copper). As I live on the first floor, but have full "sole" use of the garden I attached one end of the wire near to my entrance door (18'/20' from the ground) and it slopes about 60' down to the end fence panel at the bottom of the garden. I have then run the wire back along the top of the fence about another 42' (I have measured by counting the 6 foot fence panels) and about 4' from the ground. This gives a sort of wedge shape wire antenna (as opposed to an inverted L). I have attached the wire via home made insulators (made from pieces of drilled 1" plastic pipe) at both ends and have attached the coax (TV grade) directly to the wire at the end near my entrance door. This is then attached to th "Li-Z" phono antenna socket at the back of my DX-394 (B revision). Bearing in mind that the ATN reception is not brilliant but listenable, does my antenna sound as though it is OK or do ATN really broadcast from my neighbours house and is therefore the antenna is crap ![]() I have no antenna tuner or other equipment (wouldn't know how to use them even if I did). What other things can I do to improve things, especially in the lower 1-3Mhz where I get awful noise (I do not get a huge amount of noise above this and the higher the freq the less noise I get). Regards MC Hiya :-) Sounds like a good solution to me. I'm not an expert, but I think the key to having a good antenna isn't really how much wire you have, or what shape it is in. What is best is to have an antenna that is constructed to give you a good "signal to noise ratio" That meaning, if you have an antenna; even a very long one, that is close to an electronic noise source, your antenna probably won't be too good. You will get lots of noise and static and it will drown out lots of good DX. If you live in a densely populated area like I do here in the NY/NJ metro area, noise is always a factor. One of my antennas is a 200' random wire. It works great now, but when I first set it up, it wasn't so good. At first, I had 400' of wire. I got a lot of noise with it, and even worse then that, I would hear the local 50 kilowatt AM stations all over the band. After reading a few articles and getting some advice from other DX'ers, I made some modifications to the antenna. I shortened it to 200' and I made three additions to the antenna's construction that really helped with noise. I used a coax feed line from the receiving wire into the radio and I added a matching transformer between the coax feed and the receiving wire. I also set up a ground wire that goes from the radio's ground connection, to the ground connection on my matching transformer and then into the earth. Since those additions, the antenna is now a prime DX'ing antenna with great signal to noise ratio. So... The longer antenna at 400' didn't work so good, but the shorter one does. I think your wire antenna will probably work good. You have more then enough receiving wire, and a coax feed. If you want to try to improve on it, you may want to try using a matching transformer between your receiving wire and your coax feed. Also... It couldn't hurt to set up a ground if you already haven't. Again, though... I think the all important factor is the location of the antenna rather then the size or shape. Your antenna, if set up near serious noise sources won't work good no matter what you do. If you take that same antenna and set it up out in the wilderness far away from any noise sources... VIOLA ... You got a prime DX'ing antenna :-) Hope that helps... -- Respectfully, Michael Location: Northern NJ Primary Radio: R-75 with full Kiwa mods. Antennas: 200ft "Frankenstein" roof wire, G5RV Additional Radios:GE Super Radio III, PL-550, KA-1101, KA-1102, Kaiwa KA-989, Info-Mate 837, Westinghouse H-104 (seven tube) Home Page: http://md_dxing.tripod.com/ |
#2
![]() |
|||
|
|||
![]() "Michael" wrote in message . .. Hiya :-) Sounds like a good solution to me. I'm not an expert, but I think the key to having a good antenna isn't really how much wire you have, or what shape it is in. What is best is to have an antenna that is constructed to give you a good "signal to noise ratio" That meaning, if you have an antenna; even a very long one, that is close to an electronic noise source, your antenna probably won't be too good. You will get lots of noise and static and it will drown out lots of good DX. If you live in a densely populated area like I do here in the NY/NJ metro area, noise is always a factor. One of my antennas is a 200' random wire. It works great now, but when I first set it up, it wasn't so good. At first, I had 400' of wire. I got a lot of noise with it, and even worse then that, I would hear the local 50 kilowatt AM stations all over the band. After reading a few articles and getting some advice from other DX'ers, I made some modifications to the antenna. I shortened it to 200' and I made three additions to the antenna's construction that really helped with noise. I used a coax feed line from the receiving wire into the radio and I added a matching transformer between the coax feed and the receiving wire. I also set up a ground wire that goes from the radio's ground connection, to the ground connection on my matching transformer and then into the earth. Since those additions, the antenna is now a prime DX'ing antenna with great signal to noise ratio. So... The longer antenna at 400' didn't work so good, but the shorter one does. I think your wire antenna will probably work good. You have more then enough receiving wire, and a coax feed. If you want to try to improve on it, you may want to try using a matching transformer between your receiving wire and your coax feed. Also... It couldn't hurt to set up a ground if you already haven't. Again, though... I think the all important factor is the location of the antenna rather then the size or shape. Your antenna, if set up near serious noise sources won't work good no matter what you do. If you take that same antenna and set it up out in the wilderness far away from any noise sources... VIOLA ... You got a prime DX'ing antenna :-) Hope that helps... -- Respectfully, Michael Thanks for the input. I'm in the middle of town (more or less) but most utility cables are underground. However, my garden is enclosed amongst the buildings, mixture of residential and retail (none more that 2 floors, ground and first). I have grounded the antenna at the farthest end of the wire (nearest to the ground). I have not grounded the coax though as it is not pactical due to the distance between the coax and the ground itself. The other alternative would mean creating an unhappy wife should I run wire around the flat seeking out the nearest water pipe. Regards MC |
Reply |
Thread Tools | Search this Thread |
Display Modes | |
|
|
![]() |
||||
Thread | Forum | |||
Discone antenna plans | Antenna | |||
Yaesu FT-857D questions | Equipment | |||
Short STACKED Vertical {Tri-Band} BroomStick Antenna [Was: Wire ant question] | Shortwave | |||
Understanding Shortwave Radio Listening and Antenna Design and Construction | Shortwave | |||
EH Antenna Revisited | Antenna |