Outside Antenna
Hi
I am wondering if I have my longwire set correctly, maybe you could advise please. At the moment I have a sloping long-wire of about 50 foot, going from the top of a mast on my house about 35 foot tall to the top of a washing line post about 12 foot tall. I have connected the lonwire to my radio by means of CB-coax, what I have done is to attach the centre core of the coax to the longwire and I have cut the outer sheath on the coax near to the ground and connected an earhtwire that is soldered to a cold water main supply pipe as an earth. Only the centre wire on the coax is connected to the actual longwire. Is there a way I could do better. I am thinking about getting an active antenna, the Sony AN-1 Would this work better for me or is there a better alternative available. I am running an Icom R72 thanks Rikk |
Outside Antenna
On Sun, 05 Mar 2006 13:25:52 GMT, "Rikk"
wrote: Hi I am wondering if I have my longwire set correctly, maybe you could advise please. At the moment I have a sloping long-wire of about 50 foot, going from the top of a mast on my house about 35 foot tall to the top of a washing line post about 12 foot tall. I have connected the lonwire to my radio by means of CB-coax, what I have done is to attach the centre core of the coax to the longwire and I have cut the outer sheath on the coax near to the ground and connected an earhtwire that is soldered to a cold water main supply pipe as an earth. Only the centre wire on the coax is connected to the actual longwire. Is there a way I could do better. I am thinking about getting an active antenna, the Sony AN-1 Would this work better for me or is there a better alternative available. I am running an Icom R72 thanks Rikk You're losing at least half your signal. These match the wire to the cable. http://www.geocities.com/qrp_baluns/LM.html |
Outside Antenna
Rikk wrote: Hi I am wondering if I have my longwire set correctly, maybe you could advise please. At the moment I have a sloping long-wire of about 50 foot, going from the top of a mast on my house about 35 foot tall to the top of a washing line post about 12 foot tall. I have connected the lonwire to my radio by means of CB-coax, what I have done is to attach the centre core of the coax to the longwire and I have cut the outer sheath on the coax near to the ground and connected an earhtwire that is soldered to a cold water main supply pipe as an earth. Only the centre wire on the coax is connected to the actual longwire. Is there a way I could do better. I am thinking about getting an active antenna, the Sony AN-1 Would this work better for me or is there a better alternative available. I am running an Icom R72 thanks Rikk This looks like a good design. An AN-LP1 wil not do much compared to your current rig. What are the RF conditions like ; is it a " radio Quiet / Electronics Quiet"rural area or are ou in the midst of an urban area.. |
Outside Antenna
You'll see a huge improvement if you using a matching transformer between
the long wire and the coax. Also try to keep that matching transformer as far from the house as possible. "Rikk" wrote in message ... Hi I am wondering if I have my longwire set correctly, maybe you could advise please. At the moment I have a sloping long-wire of about 50 foot, going from the top of a mast on my house about 35 foot tall to the top of a washing line post about 12 foot tall. I have connected the lonwire to my radio by means of CB-coax, what I have done is to attach the centre core of the coax to the longwire and I have cut the outer sheath on the coax near to the ground and connected an earhtwire that is soldered to a cold water main supply pipe as an earth. Only the centre wire on the coax is connected to the actual longwire. Is there a way I could do better. I am thinking about getting an active antenna, the Sony AN-1 Would this work better for me or is there a better alternative available. I am running an Icom R72 thanks Rikk |
Outside Antenna
Hi
I live in a rural area. nearest city is 6 miles thanks Rikk wrote in message ups.com... Rikk wrote: Hi I am wondering if I have my longwire set correctly, maybe you could advise please. At the moment I have a sloping long-wire of about 50 foot, going from the top of a mast on my house about 35 foot tall to the top of a washing line post about 12 foot tall. I have connected the lonwire to my radio by means of CB-coax, what I have done is to attach the centre core of the coax to the longwire and I have cut the outer sheath on the coax near to the ground and connected an earhtwire that is soldered to a cold water main supply pipe as an earth. Only the centre wire on the coax is connected to the actual longwire. Is there a way I could do better. I am thinking about getting an active antenna, the Sony AN-1 Would this work better for me or is there a better alternative available. I am running an Icom R72 thanks Rikk This looks like a good design. An AN-LP1 wil not do much compared to your current rig. What are the RF conditions like ; is it a " radio Quiet / Electronics Quiet"rural area or are ou in the midst of an urban area.. |
Outside Antenna
"David" wrote in message ... On Sun, 05 Mar 2006 13:25:52 GMT, "Rikk" wrote: Hi I am wondering if I have my longwire set correctly, maybe you could advise please. At the moment I have a sloping long-wire of about 50 foot, going from the top of a mast on my house about 35 foot tall to the top of a washing line post about 12 foot tall. I have connected the lonwire to my radio by means of CB-coax, what I have done is to attach the centre core of the coax to the longwire and I have cut the outer sheath on the coax near to the ground and connected an earhtwire that is soldered to a cold water main supply pipe as an earth. Only the centre wire on the coax is connected to the actual longwire. Is there a way I could do better. I am thinking about getting an active antenna, the Sony AN-1 Would this work better for me or is there a better alternative available. I am running an Icom R72 thanks Rikk You're losing at least half your signal. These match the wire to the cable. http://www.geocities.com/qrp_baluns/LM.html Hi David I visited the website you mentioned. and think the LMZ-50 would be best for me. How exactly does this work please, do I simply connect the longwire to the balun, and the run coax from balun to radio via cb coax. thanks Rikk |
Outside Antenna
That sounds like a good rig, but it is going to be more efficient at lower
frequencies. You might rig up another one about 1/4 that length and use it for higher frequencies. 50 feet=50x3.28=164 meters 300/164=1.8 Mhz which is in medium wave band 12 feet=41 meters 300/42=7.31 6 feet=19.68 meters 300/19.68=15.24 Mhz While it isn't necessary to have an exact match, down to the millimeter, getting the length nearly correct is important, because of the signal strength losses mentioned in the previous post. This is why a longwire is very useful for very low frequencies. At higher frequencies you get more noise than signal. If you try to use a high power transmitter with an antenna badly matched for the band on which you are transmitting, most of your energy will simply comes crashing back at your trasmitter and burn up your circuitry s. Some lucky individuals intersted in very low frequency phenomena have the space to run wires miles in length, and need special arrangements to accommodate the incredible voltages generated. Many very strange natural signals lurk on frequencies that would be voice frequencies if they were sound, and are very strange indeed. http://www.auroralchorus.com/wr3gde.htm He has some interesting recordings at another link you can find on that site. HTH V HTH V. All life all holiness come from you O Lord "Rikk" wrote in message ... Hi I live in a rural area. nearest city is 6 miles thanks Rikk wrote in message ups.com... Rikk wrote: Hi I am wondering if I have my longwire set correctly, maybe you could advise please. At the moment I have a sloping long-wire of about 50 foot, going from the top of a mast on my house about 35 foot tall to the top of a washing line post about 12 foot tall. I have connected the lonwire to my radio by means of CB-coax, what I have done is to attach the centre core of the coax to the longwire and I have cut the outer sheath on the coax near to the ground and connected an earhtwire that is soldered to a cold water main supply pipe as an earth. Only the centre wire on the coax is connected to the actual longwire. Is there a way I could do better. I am thinking about getting an active antenna, the Sony AN-1 Would this work better for me or is there a better alternative available. I am running an Icom R72 thanks Rikk This looks like a good design. An AN-LP1 wil not do much compared to your current rig. What are the RF conditions like ; is it a " radio Quiet / Electronics Quiet"rural area or are ou in the midst of an urban area.. |
Outside Antenna
On Sun, 05 Mar 2006 16:11:09 GMT, "Rikk"
wrote: Hi David I visited the website you mentioned. and think the LMZ-50 would be best for me. How exactly does this work please, do I simply connect the longwire to the balun, and the run coax from balun to radio via cb coax. thanks Rikk You can use plain old RG-6 Cable TV coax if you like. You use a 75 Ohm matcher at the antenna and the appropriate mechanical adapter at the receiver. If you have a portable, use a flexible adapter to keep strain off the little plug. |
Outside Antenna
"Rikk" wrote in message ... Hi I am wondering if I have my longwire set correctly, maybe you could advise please. At the moment I have a sloping long-wire of about 50 foot, going from the top of a mast on my house about 35 foot tall to the top of a washing line post about 12 foot tall. I have connected the lonwire to my radio by means of CB-coax, what I have done is to attach the centre core of the coax to the longwire and I have cut the outer sheath on the coax near to the ground and connected an earhtwire that is soldered to a cold water main supply pipe as an earth. Only the centre wire on the coax is connected to the actual longwire. Is there a way I could do better. I am thinking about getting an active antenna, the Sony AN-1 Would this work better for me or is there a better alternative available. I am running an Icom R72 thanks Rikk Hi Guys Thanks all very much for your help, I appreciate your comments, I have opted to order a balun from a supplier mention on this thread and see how it goes from there. I shall also try a few of your other suggestions as they are really interesting in therory. As you can probably see, I am relativly new to sw and until now have been using the SW77 on it's telescopic antenna, but time for me to move forward a bit, so I will see what I can do with the R72 thanks again Rikk United Kingdom |
Outside Antenna
It's not a given that cutting back the antenna will yield better
reception. You are reducing the aperture. Verstaldin wrote: That sounds like a good rig, but it is going to be more efficient at lower frequencies. You might rig up another one about 1/4 that length and use it for higher frequencies. 50 feet=50x3.28=164 meters 300/164=1.8 Mhz which is in medium wave band 12 feet=41 meters 300/42=7.31 6 feet=19.68 meters 300/19.68=15.24 Mhz While it isn't necessary to have an exact match, down to the millimeter, getting the length nearly correct is important, because of the signal strength losses mentioned in the previous post. This is why a longwire is very useful for very low frequencies. At higher frequencies you get more noise than signal. If you try to use a high power transmitter with an antenna badly matched for the band on which you are transmitting, most of your energy will simply comes crashing back at your trasmitter and burn up your circuitry s. Some lucky individuals intersted in very low frequency phenomena have the space to run wires miles in length, and need special arrangements to accommodate the incredible voltages generated. Many very strange natural signals lurk on frequencies that would be voice frequencies if they were sound, and are very strange indeed. http://www.auroralchorus.com/wr3gde.htm He has some interesting recordings at another link you can find on that site. HTH V HTH V. All life all holiness come from you O Lord "Rikk" wrote in message ... Hi I live in a rural area. nearest city is 6 miles thanks Rikk wrote in message ups.com... Rikk wrote: Hi I am wondering if I have my longwire set correctly, maybe you could advise please. At the moment I have a sloping long-wire of about 50 foot, going from the top of a mast on my house about 35 foot tall to the top of a washing line post about 12 foot tall. I have connected the lonwire to my radio by means of CB-coax, what I have done is to attach the centre core of the coax to the longwire and I have cut the outer sheath on the coax near to the ground and connected an earhtwire that is soldered to a cold water main supply pipe as an earth. Only the centre wire on the coax is connected to the actual longwire. Is there a way I could do better. I am thinking about getting an active antenna, the Sony AN-1 Would this work better for me or is there a better alternative available. I am running an Icom R72 thanks Rikk This looks like a good design. An AN-LP1 wil not do much compared to your current rig. What are the RF conditions like ; is it a " radio Quiet / Electronics Quiet"rural area or are ou in the midst of an urban area.. |
Outside Antenna
How did you solder that ground wire to that water pipe?
cuhulin |
Outside Antenna
wrote in message ... How did you solder that ground wire to that water pipe? cuhulin Hi I just cleaned the pipe itself with a wire brush till it was shining like new, got a jubilee clip ( car hose clip) and put the ground wire through the clip, tightened the clip on the pipe then used my heavy duty solder gun, I ran a test with my multimeter and it is giving a good ground. cheers Rikk |
Outside Antenna
About four years ago,that married Irish woman in Bognor Regis,England
hired a guy to repair a leaky pipe in their toilet.The guy didn't know anything at all about doing plumbing repair jobs.He tried to solder that leaky pipe instead of replacing the leaky pipe with a new pipe.I guess old Tony bought quite a few pints at the pubs over there with the money they paid him. cuhulin |
Outside Antenna
On Sun, 05 Mar 2006 13:25:52 GMT, "Rikk"
wrote: Hi I am wondering if I have my longwire set correctly, maybe you could advise please. At the moment I have a sloping long-wire of about 50 foot, going from the top of a mast on my house about 35 foot tall to the top of a washing line post about 12 foot tall. I have connected the lonwire to my radio by means of CB-coax, what I have done is to attach the centre core of the coax to the longwire and I have cut the outer sheath on the coax near to the ground and connected an earhtwire that is soldered to a cold water main supply pipe as an earth. Only the centre wire on the coax is connected to the actual longwire. Is there a way I could do better. I am thinking about getting an active antenna, the Sony AN-1 Would this work better for me or is there a better alternative available. I am running an Icom R72 thanks Rikk If you don't have too much man-made noise inside your house, you might consider bringing the random wire all the way to the 500-ohm terminal on the back of your receiver, and run your ground wire from the terminal next to it to your cold water pipe. This gets rid of the mismatch between your high impedance antenna and low impedance coax, and you don't need the balun at all, which is fine, because the balun only provides an approximate impedance transformation. Another alternative would be to bring the long wire into your house, and attach it to an inexpensive random wire antenna tuner, such as an MFJ 16010, about $49 US. Then run a short length of coax from the tuner to your radio's 50-ohm input. As you go to each new frequency, peak the knobs for maximum signal strength. Yet another alternative, keep your current antenna; add the balun to it or whatever. But put up a 2nd antenna, perhaps aimed in a different direction, and run it to your high impedance terminal. Switch between the two antennas for best reception on a given signal. You could do some interesting A-B comparisons on antennas. Bob k5qwg |
Outside Antenna
In article ,
"Rikk" wrote: "Rikk" wrote in message ... Hi I am wondering if I have my longwire set correctly, maybe you could advise please. At the moment I have a sloping long-wire of about 50 foot, going from the top of a mast on my house about 35 foot tall to the top of a washing line post about 12 foot tall. I have connected the lonwire to my radio by means of CB-coax, what I have done is to attach the centre core of the coax to the longwire and I have cut the outer sheath on the coax near to the ground and connected an earhtwire that is soldered to a cold water main supply pipe as an earth. Only the centre wire on the coax is connected to the actual longwire. Is there a way I could do better. I am thinking about getting an active antenna, the Sony AN-1 Would this work better for me or is there a better alternative available. I am running an Icom R72 thanks Rikk Hi Guys Thanks all very much for your help, I appreciate your comments, I have opted to order a balun from a supplier mention on this thread and see how it goes from there. I shall also try a few of your other suggestions as they are really interesting in therory. As you can probably see, I am relativly new to sw and until now have been using the SW77 on it's telescopic antenna, but time for me to move forward a bit, so I will see what I can do with the R72 thanks again You are off to a good start and as someone else in the thread already mentioned you could improve the random wire performance with a UNUN impedance matching transformer at the coax/random wire junction. This wire should already be working better then the whip. You can tune through the bands to get an idea how well it is working. Usually good wire performance will start at the 1/4 wavelength frequency of the wire length and will work well from that frequency on up except at even multiples of that 1/4 wavelength so 1/2 wavelength would not be good. As long as the even multiple does not fall on a SW band you are OK. Some people use more than one wire. I think this is a game plan that DxAce uses with two separate wires one twice the length of the other. I think he uses a 100 and 200 foot lengths. Where one would be at zero volts at the end of the wire the other would be at maximum. If at a non-resonate wavelength they could look the same. Since your long length is 50 foot you tie on another 25 foot wire at the coax junction and hang the far end off the 50 foot wire a few feet with an insulator of fishing line as an example. Not as clean as two separate wires but it should work well. A 50 foot wire in air should be 1/4 wave resonate at about 9.7 MHz. The 9 MHz band would be your best to pick up signals with the 50 foot wire. -- Telamon Ventura, California |
Outside Antenna
Telamon wrote: In article , "Rikk" wrote: "Rikk" wrote in message ... Hi I am wondering if I have my longwire set correctly, maybe you could advise please. At the moment I have a sloping long-wire of about 50 foot, going from the top of a mast on my house about 35 foot tall to the top of a washing line post about 12 foot tall. I have connected the lonwire to my radio by means of CB-coax, what I have done is to attach the centre core of the coax to the longwire and I have cut the outer sheath on the coax near to the ground and connected an earhtwire that is soldered to a cold water main supply pipe as an earth. Only the centre wire on the coax is connected to the actual longwire. Is there a way I could do better. I am thinking about getting an active antenna, the Sony AN-1 Would this work better for me or is there a better alternative available. I am running an Icom R72 thanks Rikk Hi Guys Thanks all very much for your help, I appreciate your comments, I have opted to order a balun from a supplier mention on this thread and see how it goes from there. I shall also try a few of your other suggestions as they are really interesting in therory. As you can probably see, I am relativly new to sw and until now have been using the SW77 on it's telescopic antenna, but time for me to move forward a bit, so I will see what I can do with the R72 thanks again You are off to a good start and as someone else in the thread already mentioned you could improve the random wire performance with a UNUN impedance matching transformer at the coax/random wire junction. This wire should already be working better then the whip. You can tune through the bands to get an idea how well it is working. Usually good wire performance will start at the 1/4 wavelength frequency of the wire length and will work well from that frequency on up except at even multiples of that 1/4 wavelength so 1/2 wavelength would not be good. As long as the even multiple does not fall on a SW band you are OK. Some people use more than one wire. I think this is a game plan that DxAce uses with two separate wires one twice the length of the other. I think he uses a 100 and 200 foot lengths. Where one would be at zero volts at the end of the wire the other would be at maximum. If at a non-resonate wavelength they could look the same. Since your long length is 50 foot you tie on another 25 foot wire at the coax junction and hang the far end off the 50 foot wire a few feet with an insulator of fishing line as an example. Not as clean as two separate wires but it should work well. A 50 foot wire in air should be 1/4 wave resonate at about 9.7 MHz. The 9 MHz band would be your best to pick up signals with the 50 foot wire. I'm using a 70' wire running N-S and a 200' wire running W-E. dxAce Michigan USA |
Outside Antenna
And after she had her bathroom completely remodeled (she got ahold of a
plumbing company by the name of Brough,or something like that) after that Tony guy messed it all up,she emailed me a photo of her newly remodeled bathroom.But the photo is turned 90 degrees to the left.I have to crane my head 90 degrees to see the photo right side up. cuhulin |
Outside Antenna
Rikk wrote:
"Rikk" wrote in message ... Hi I am wondering if I have my longwire set correctly, maybe you could advise please. At the moment I have a sloping long-wire of about 50 foot, going from the top of a mast on my house about 35 foot tall to the top of a washing line post about 12 foot tall. I have connected the lonwire to my radio by means of CB-coax, what I have done is to attach the centre core of the coax to the longwire and I have cut the outer sheath on the coax near to the ground and connected an earhtwire that is soldered to a cold water main supply pipe as an earth. Only the centre wire on the coax is connected to the actual longwire. Is there a way I could do better. I am thinking about getting an active antenna, the Sony AN-1 Would this work better for me or is there a better alternative available. I am running an Icom R72 thanks Rikk Hi Guys Thanks all very much for your help, I appreciate your comments, I have opted to order a balun from a supplier mention on this thread and see how it goes from there. I shall also try a few of your other suggestions as they are really interesting in therory. As you can probably see, I am relativly new to sw and until now have been using the SW77 on it's telescopic antenna, but time for me to move forward a bit, so I will see what I can do with the R72 thanks again Rikk United Kingdom The antenna configuration you have is similar to a 'sloper' design where one end is higher than the other. To reduce the reception of noise from appliances in your home, it's better to locate the balun (unun) near the ground (earth) instead of in the air at the end of the antenna. This means you should extend the feed end of the antenna to the ground with a single vertical wire (not coax) and connect that wire to the high impedance input of the balun. The low impedance output of the balun goes to the coax that should run on/in the ground to the house. Having the balun and coax near the ground will allow you to use a short ground wire from the balun to a ground rod near by. This helps to keep noise off the shield of the coax. This antenna system (inverted-L) works best if both ends of the horizontal section are located away from the house. In your case you can make the far end of the antenna at the wash line pole the feed end with the vertical wire to the balun near the ground. Instead of having the near end come all the way to the mast on the house, shorten it about 20-ft and install an insulator at that end with some nylon rope to the mast. This will keep the near end of the antenna away from the house, where it could pick up noise. The vertical wire at the other end will make up for shortening the antenna at the house end. It will also help to receive signals which arrive at the antenna from a low angle to the horizon. My antenna is very similar except I installed a 20-ft metal pole on top of the wooden clothes line pole to make that end higher above ground. This also makes the vertical wire longer for better reception. |
Outside Antenna
David wrote:
On Sun, 5 Mar 2006 14:32:09 -0600, wrote: About four years ago,that married Irish woman in Bognor Regis,England hired a guy to repair a leaky pipe in their toilet.The guy didn't know anything at all about doing plumbing repair jobs.He tried to solder that leaky pipe instead of replacing the leaky pipe with a new pipe.I guess old Tony bought quite a few pints at the pubs over there with the money they paid him. cuhulin http://www.daveswebshop.com/pvagc1.shtml These come in two styles. The zinc (or aluminium?) style is for indoor, dry locations. The brass version may be buried in the soil. I'd use an anti oxidant such as Penetrox or NoAlox on the screws and joint if burying the connection. mike |
Outside Antenna
In article ,
dxAce wrote: Telamon wrote: In article , "Rikk" wrote: "Rikk" wrote in message ... Hi I am wondering if I have my longwire set correctly, maybe you could advise please. At the moment I have a sloping long-wire of about 50 foot, going from the top of a mast on my house about 35 foot tall to the top of a washing line post about 12 foot tall. I have connected the lonwire to my radio by means of CB-coax, what I have done is to attach the centre core of the coax to the longwire and I have cut the outer sheath on the coax near to the ground and connected an earhtwire that is soldered to a cold water main supply pipe as an earth. Only the centre wire on the coax is connected to the actual longwire. Is there a way I could do better. I am thinking about getting an active antenna, the Sony AN-1 Would this work better for me or is there a better alternative available. I am running an Icom R72 thanks Rikk Hi Guys Thanks all very much for your help, I appreciate your comments, I have opted to order a balun from a supplier mention on this thread and see how it goes from there. I shall also try a few of your other suggestions as they are really interesting in therory. As you can probably see, I am relativly new to sw and until now have been using the SW77 on it's telescopic antenna, but time for me to move forward a bit, so I will see what I can do with the R72 thanks again You are off to a good start and as someone else in the thread already mentioned you could improve the random wire performance with a UNUN impedance matching transformer at the coax/random wire junction. This wire should already be working better then the whip. You can tune through the bands to get an idea how well it is working. Usually good wire performance will start at the 1/4 wavelength frequency of the wire length and will work well from that frequency on up except at even multiples of that 1/4 wavelength so 1/2 wavelength would not be good. As long as the even multiple does not fall on a SW band you are OK. Some people use more than one wire. I think this is a game plan that DxAce uses with two separate wires one twice the length of the other. I think he uses a 100 and 200 foot lengths. Where one would be at zero volts at the end of the wire the other would be at maximum. If at a non-resonate wavelength they could look the same. Since your long length is 50 foot you tie on another 25 foot wire at the coax junction and hang the far end off the 50 foot wire a few feet with an insulator of fishing line as an example. Not as clean as two separate wires but it should work well. A 50 foot wire in air should be 1/4 wave resonate at about 9.7 MHz. The 9 MHz band would be your best to pick up signals with the 50 foot wire. I'm using a 70' wire running N-S and a 200' wire running W-E. Were the two different lengths intentional or that they fit your home lot? The different lengths do work in your favor. -- Telamon Ventura, California |
Outside Antenna
In article ,
dxAce wrote: Telamon wrote: In article , dxAce wrote: Telamon wrote: In article , "Rikk" wrote: "Rikk" wrote in message ... Hi I am wondering if I have my longwire set correctly, maybe you could advise please. At the moment I have a sloping long-wire of about 50 foot, going from the top of a mast on my house about 35 foot tall to the top of a washing line post about 12 foot tall. I have connected the lonwire to my radio by means of CB-coax, what I have done is to attach the centre core of the coax to the longwire and I have cut the outer sheath on the coax near to the ground and connected an earhtwire that is soldered to a cold water main supply pipe as an earth. Only the centre wire on the coax is connected to the actual longwire. Is there a way I could do better. I am thinking about getting an active antenna, the Sony AN-1 Would this work better for me or is there a better alternative available. I am running an Icom R72 thanks Rikk Hi Guys Thanks all very much for your help, I appreciate your comments, I have opted to order a balun from a supplier mention on this thread and see how it goes from there. I shall also try a few of your other suggestions as they are really interesting in therory. As you can probably see, I am relativly new to sw and until now have been using the SW77 on it's telescopic antenna, but time for me to move forward a bit, so I will see what I can do with the R72 thanks again You are off to a good start and as someone else in the thread already mentioned you could improve the random wire performance with a UNUN impedance matching transformer at the coax/random wire junction. This wire should already be working better then the whip. You can tune through the bands to get an idea how well it is working. Usually good wire performance will start at the 1/4 wavelength frequency of the wire length and will work well from that frequency on up except at even multiples of that 1/4 wavelength so 1/2 wavelength would not be good. As long as the even multiple does not fall on a SW band you are OK. Some people use more than one wire. I think this is a game plan that DxAce uses with two separate wires one twice the length of the other. I think he uses a 100 and 200 foot lengths. Where one would be at zero volts at the end of the wire the other would be at maximum. If at a non-resonate wavelength they could look the same. Since your long length is 50 foot you tie on another 25 foot wire at the coax junction and hang the far end off the 50 foot wire a few feet with an insulator of fishing line as an example. Not as clean as two separate wires but it should work well. A 50 foot wire in air should be 1/4 wave resonate at about 9.7 MHz. The 9 MHz band would be your best to pick up signals with the 50 foot wire. I'm using a 70' wire running N-S and a 200' wire running W-E. Were the two different lengths intentional or that they fit your home lot? The different lengths do work in your favor. Pretty much intentional, but they fit my lot which is 85' wide by 463 deep. I do have a bit of leeway with the neighbours permission for some longer lengths, but this setup seems to work fairly well, and my target list these days is quite short, at least country wise. I'm quite envious of the fact that you can use that type of antenna. Much to electrically noisy around here for me to do that and about 40 feet is the best I can do anyway on this small lot. -- Telamon Ventura, California |
Outside Antenna
HF Guy,
Good Inverted "L" Antenna lay-out suggestion and a good discription on how-to put it all together. iane ~ RHF |
Outside Antenna
"HFguy" wrote in message news:NLMOf.920$6h1.61@trndny09... Rikk wrote: "Rikk" wrote in message ... Hi I am wondering if I have my longwire set correctly, maybe you could advise please. At the moment I have a sloping long-wire of about 50 foot, going from the top of a mast on my house about 35 foot tall to the top of a washing line post about 12 foot tall. I have connected the lonwire to my radio by means of CB-coax, what I have done is to attach the centre core of the coax to the longwire and I have cut the outer sheath on the coax near to the ground and connected an earhtwire that is soldered to a cold water main supply pipe as an earth. Only the centre wire on the coax is connected to the actual longwire. Is there a way I could do better. I am thinking about getting an active antenna, the Sony AN-1 Would this work better for me or is there a better alternative available. I am running an Icom R72 thanks Rikk Hi Guys Thanks all very much for your help, I appreciate your comments, I have opted to order a balun from a supplier mention on this thread and see how it goes from there. I shall also try a few of your other suggestions as they are really interesting in therory. As you can probably see, I am relativly new to sw and until now have been using the SW77 on it's telescopic antenna, but time for me to move forward a bit, so I will see what I can do with the R72 thanks again Rikk United Kingdom The antenna configuration you have is similar to a 'sloper' design where one end is higher than the other. To reduce the reception of noise from appliances in your home, it's better to locate the balun (unun) near the ground (earth) instead of in the air at the end of the antenna. This means you should extend the feed end of the antenna to the ground with a single vertical wire (not coax) and connect that wire to the high impedance input of the balun. The low impedance output of the balun goes to the coax that should run on/in the ground to the house. Having the balun and coax near the ground will allow you to use a short ground wire from the balun to a ground rod near by. This helps to keep noise off the shield of the coax. This antenna system (inverted-L) works best if both ends of the horizontal section are located away from the house. In your case you can make the far end of the antenna at the wash line pole the feed end with the vertical wire to the balun near the ground. Instead of having the near end come all the way to the mast on the house, shorten it about 20-ft and install an insulator at that end with some nylon rope to the mast. This will keep the near end of the antenna away from the house, where it could pick up noise. The vertical wire at the other end will make up for shortening the antenna at the house end. It will also help to receive signals which arrive at the antenna from a low angle to the horizon. My antenna is very similar except I installed a 20-ft metal pole on top of the wooden clothes line pole to make that end higher above ground. This also makes the vertical wire longer for better reception. Thanks very much HF Guy, for your excellent suggestion and easy to follow instructions. I am obliged to you regards Rikk UK |
Question : What Will . . . My Second Shortwave Listener (SWL) Antenna Be ? {Making Use of the High-Z (500 Ohm) Terminals} - Think Windom Antenna with 300 Ohm Feed-in-Line !
BM [K5QWG] - Those were Three Good Antenna Suggestions.
IF - The Low-Z (50 Ohm) SO-239 Connector on the Receiver is being used for some sort of LongWire {Random Wire} Antenna that is using a Matching Transformer and a Coax Cable Feed-in-Line. NOTE - My Favorite is the Inverted "L" Antenna with with the Vertical-Up-Leg at the Far-End and a Remotely Located Ground Rod at base of the Far-End of the Antenna; also using a Matching Transformer (UnUn) between the Wire Antenna Element and the Coax Cable Feed-in-Line and having the Coax Cable run directly under the Horizontal Arm of the Antenna. READ - ABOUT - The "Low Noise" Antenna design concepts that were popularized by John Doty : http://groups.google.com/group/rec.r...86383afa7727a9 http://groups.google.com/group/rec.r...38b087b5e89fee http://groups.yahoo.com/group/Shortw...a/message/5178 http://groups.google.com/group/rec.r...463ad863e5b075 http://groups.google.com/group/rec.r...4620d18b66eeba http://groups.google.com/group/rec.r...3fe02cad4e5650 http://groups.google.com/group/rec.r...d35eeaa8425c14 http://groups.google.com/group/rec.r...7711375bb4d0bb THEN CONSIDER A SECOND SHORTWAVE ANTENNA - - - THINK WINDOM ANTENNA ! ! ! As you observe the High-Z Terminals (500 Ohm) are not being used. So the High-Z Terminals (500 Ohm) are available to connect a Second (2nd) "Alternate" {Back-Up} Antenna to the Receiver. QUESTION : What Will . . . My Second Shortwave Listener (SWL) Antenna Be ? {Making Use of the High-Z (500 Ohm) Terminals} ! Think Windom Antenna with 300 Ohm Feed-in-Line ! My Choice for this Second "Alternate" {Back-Up} Antenna is a Windom Antenna using 300 Ohm TV type Twin Lead as the Feed-in-Line and simple 20 AWG Hook-Up Wire as the Wire Antenna Elements. The Two 'un-equal' Horizontal-Arms of the Windom Antenna can be Cut for your Target Shortwave Bands or simply Cut-to-Fit the Available Space allowed by your Lot (Land). TIP - The Off-Center {Center} Connector for your Windom * Ten-Tec 3003 Acro-Bat (Dipole Antenna Hanger) http://www.universal-radio.com/catalog/antsup/3720.html Windom Antenna = Available Space Tip-to-Tip (T2T) Length * Short Horizontal-Arm 33% ~ 38% of T2T Length * Long Horizontal-Arm 62% ~ 67% of T2T Length * How High ? Rigged the Windom at 25% of T2T Length Windom Antenna = Cut-to-Shortwave-Band Large Size - Windom Antenna {~ 100 Feet} Cut for : 60 Meters = 75 Meters + 49 Meters T2T = 97.7 Ft = 59.2 Ft + 38.5 Ft and Rigged at 24.5 Ft High Medium Size - Windom Antenna {~ 65 Feet} Cut for : 41 Meters = 49 Meters + 31 Meters T2T = 63.0 Ft = 38.5 Ft + 24.5 and Rigged at 17.1 Ft High Small Size - Windom Antenna {~ 50 Feet} Cut for : 31 Meters = 41 Meters + 25 Meters T2T = 51.5 Ft = 31.8 Ft + 19.7 Ft and Rigged at 15.1 Ft High Mini Size - Windom Antenna {~ 40 Feet} Cut for : 25 Meters = 31 Meters + 19 Meters T2T = 39.6 Ft = 24.5 Ft + 15.1 Ft and Rigged at 10.8 Ft High RIGGING - Ideally the 300 Ohm Twin Lead Vertical-Up-Leg of the Windom Antenna should run Straight-Up (Vertically) from the Ground to the Off-Center Mounting Point of the Antenna and the Rule-of-Thumb for this simple type of Windom Antenna is to have the Antenna's Horizontal Arms Rigged [Flat] at about 25% of the Tip-to-Tip (T2T) Length of the Antenna. Note - The remainder of the Twin Lead Feed-in-Line can run along the Ground and then to the Receiver. READ - Windom -vice- Dipole which is the better SWL Antenna ? ? ? http://groups.google.com/group/rec.r...c69758fb501718 http://groups.yahoo.com/group/SWL-AM...nna/message/80 http://groups.yahoo.com/group/Shortw...a/message/1677 http://groups.yahoo.com/group/Shortw...a/message/1596 http://groups.yahoo.com/group/Shortw...a/message/1582 READ - History of the Windom Antenna from the Scottish Ham Portal http://www.scotham.net . . hope this helps - iane ~ RHF . Tous Sont Bienvenus ! - - - Groupe par Radio d'auditeur d'onde courte pour des Antennes de SWL http://groups.yahoo.com/group/Shortwave-SWL-Antenna/ . Alle Sind Willkommen ! - - - Shortwave Radiozuhörer Gruppe für SWL Antennen http://groups.yahoo.com/group/Shortwave-SWL-Antenna/ . Tutti Sono Benvenuti ! - - - Gruppo Radiofonico dell'ascoltatore di onda corta per le Antenne di SWL http://groups.yahoo.com/group/Shortwave-SWL-Antenna/ . Todos São Bem-vindos ! - - - Grupo de Rádio do ouvinte do Shortwave para Antenas de SWL http://groups.yahoo.com/group/Shortwave-SWL-Antenna/ . Все *адушны ! - - - Группа оператора на приеме коротковолнового диапазона Radio для Aнтенн SWL http://groups.yahoo.com/group/Shortwave-SWL-Antenna/ . ¡Todos Son Agradables! - - - Grupo de Radio del oyente de la onda corta para las Antenas de SWL http://groups.yahoo.com/group/Shortwave-SWL-Antenna/ . = = = = = Translation = = = = = All are Welcome - - - To Join the Shortwave Listeners (SWL) Antenna Group on YAHOO ! http://groups.yahoo.com/group/Shortwave-SWL-Antenna/ . . .. . |
Outside Antenna
In article et,
Verstaldin wrote: That sounds like a good rig, but it is going to be more efficient at lower frequencies. You might rig up another one about 1/4 that length and use it for higher frequencies. 50 feet=50x3.28=164 meters 300/164=1.8 Mhz which is in medium wave band I'm surprised that no one else noticed that you've reversed your conversion factor. That should be 50/3.28, not 50 * 3.28. Mark Zenier Googleproofaddress(account:mzenier provider:eskimo domain:com) |
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