Re: [AMRadio] 160 meter antenna
Jim You only need 50 feet to make a unipole on that Tower.It can Be 1 wire , 2 wire or 3 wires .up to 6 wires running down from the 50 foot point. use the fence as your Ground radials. your HAM. become creative. Ive Done it. It works. heck For a while I even used a glass Coke Bottle as an insulator on the Bottom of My 40 foot Flagpole in front of the house and loaded that up on 160 Meters. a length of thin wire and a Cluster of Helium Balloons. On a calm day Works great. Its not Hard to do.. Neal KA2CAF P.S. Does this New Jersey guy need to visit Waco to show a Texan how to Do it? Just Kidding.. Texas is great Been to Dallas /FtWorth and Berryville. My ompany has a few AM stations out there I would like to Vist one day. __ Our Main Website: http://www.amfone.net AMRadio mailing list Searchable Archives: http://www.mail-archive.com/amradio@mailman.qth.net/ List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to amradio-requ...@mailman.qth.net with the word unsubscribe in the message body.
Re: [AMRadio] 160 meter antenna
Brett wrote: Without a tuner, you can use the antenna's on receive, even on other bands, while with a tuner, if you get far from where you are tuned from, you get a lot of loss... True statement, but specifically: If the tuner is a high-pass filter, like the common T-network tuner (ultimate transmatch), frequencies lower than the resonant frequency of the system (=frequency the tuner antenna happen to be tuned to) are attenuated, and higher frequencies (up to a point) are passed with little loss. If the tuner is a low-pass filter, such as the balanced pi-network I use at one of my studios, frequencies higher than the resonant frequency of the system are attenuated, and lower frequencies (again, up tho a point) work Fine Business Old Man. If the tuner is a band-pass filter - an example would be the link-coupled parallel-tuned LC network popular for tuned feeders - there is attenuation on both sides of the resonant frequency. Brett, by the way, you were strapping into Maine last Sunday morning on 40M - could not fire up to talk to you at the time; I was working on a friend's Ranger with said friend (Steve, KM1V ex-KS1F ex KM1V) in the shack with me. 73, -Larry/NE1S __ Our Main Website: http://www.amfone.net AMRadio mailing list Searchable Archives: http://www.mail-archive.com/amradio@mailman.qth.net/ List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to amradio-requ...@mailman.qth.net with the word unsubscribe in the message body.
Re: [AMRadio] 160 meter antenna
Hi Jim, When it comes to 160-meters, you must first assess just what, exactly, you want to accomplish on the band... Do you want to work just your Stateside buddies...? If so, a half-wave dipole / inverted V at 80' will be MORE than up to the task. Feed it with open wire line, coax, whatever... Do you just wanna work DX on the band...? Then delve into the various antenna handbooks to learn how to shunt feed that tower as a vertical. Eighty feet of physical tower height translates to some 120' of electrical tower height when fed the proper way (remember to add lotsa ground radials). Do you wanna work both domestic AND DX stations, both, on Topband...? Then string up an inverted L alongside your tower. The mix of both horizontal and vertical wire will be a good compromise in the matter of working both near-in, and far-away, stations...but again, be prepared to lay down some radial wires for it to work effectively. Radial wires are a whole 'nother topic, for sure... Anyway, that's my $0.02 worth...and I've been on the band, off on, almost from the time I first got licensed some 38 years ago. ~73~ Eddy VE3CUI - VE3XZ - Original Message - From: Jim Miller WB5OXQ in Waco To: Discussion of AM Radio in the Amateur Service Sent: Sunday, January 11, 2009 11:28 PM Subject: [AMRadio] 160 meter antenna I always wanted to try am on 160 but like most do not have enough room for a full size antenna, so, I am considering building a 160 meter antenna at our clubhouse because there is a 80' tower there and over an acre of land to spread out a 1/2 wave dipole. Question is; 1 Is a 1/2 wave wire dipole the best antenna for the band considering there is room for it. 2 Is 80' high enough for the center of the inverted V? 3 How high do the ends need to be off of the ground? 4 Should I feed it with coax or ladder line to the 10' level (or other) then a balun to coax to the tuner (coax is the only acceptable line into the shack)? The shack is a metal building 30X60' and directly below the tower. There is no way to get ladder line to the operating position since all cables have to run through a 3 conduit for at least 30'. The tower is a free standing commercial tower made of 4 20' sections bolted together with a 2 meter and a 440mhz antenna at the top, all ham antennas. Thanks for any advice. Jim wb5oxq -- __ Our Main Website: http://www.amfone.net AMRadio mailing list Searchable Archives: http://www.mail-archive.com/amradio@mailman.qth.net/ List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to amradio-requ...@mailman.qth.net with the word unsubscribe in the message body.__ Our Main Website: http://www.amfone.net AMRadio mailing list Searchable Archives: http://www.mail-archive.com/amradio@mailman.qth.net/ List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to amradio-requ...@mailman.qth.net with the word unsubscribe in the message body.
Re: [AMRadio] 160 meter antenna
Neal. Thanks for the link on building the Unipole. I had worked for Sprint for some time and I noticed they were using that same concept on many of their towers. The link was exceptionally helpful -- Original message from neal Newman cozy...@yahoo.com: -- Jim you only need 50 feet of verticle space. why not just build yourself a Folded Unipole antenna if you Dont know how. Ask. its really easy. Just Run 3 lengths of #12 wire or if you have it #6 wire. short them up at around the 50 foot point and use 1" PVC Tubing as Insulators with clamps Down the side of the Tower. at the bottom Each wire is isolated with PVC from the Tower. BTW Each wire should be about 12" or more off the tower. then Tie all 3 wires together with a ring of #12 and take that as the Lead to the antenna tuner. Run at Least 4 ground radials 50 feet long If you can get the space make them 120 feet... and you will have a Killer 160 antenna. if not make an inverted L Run a wire thats 130 feet long. as far vertically as you can then run the rest out horizontally... again you need at least 4 ground radials the unipole is what we use for Broadcast stations when we are tight for height or space on a grounded Tower. Neal-KA2CAF CE- WTTM/WHWH/WJDM/WIBG/WFYL--- On Sun, 1/11/09, Jim Miller WB5OXQ in Wacowrote:From: Jim Miller WB5OXQ in Waco Subject: [AMRadio] 160 meter antenna To: "Discussion of AM Radio in the Amateur Service" Date: Sunday, January 11, 2009, 11:28 PM I always wanted to try am on 160 but like most do not have enough room for a full size antenna, so, I am considering building a 160 meter antenna at our clubhouse because there is a 80' tower there and over an acre of land to spread out a 1/2 wave dipole. Question is; 1 Is a 1/2 wave wire dipole the best antenna for the band considering there is room for it. 2 Is 80' high enough for the center of the inverted V? 3 How high do the ends need to be off of the ground? 4 Should I feed it with coax or ladder line to the 10' level (or other) then a balun to coax to the tuner (coax is the only acceptable line into the shack)? The shack is a metal building 30X60' and directly below the tower. There is no way to get ladder line to the operating position since all cables have to run through a 3" conduit for at least 30'. The tower is a free standing commercial tower made of 4 20' sections bolted together with a 2 meter and a 440mhz antenna at the top, all ham antennas. Thanks for any advice. Jim wb5oxq__ Our Main Website: http://www.amfone.net AMRadio mailing list Searchable Archives: http://www.mail-archive.com/amradio@mailman.qth.net/ List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to amradio-requ...@mailman.qth.net with the word unsubscribe in the message body. __ Our Main Website: http://www.amfone.net AMRadio mailing list Searchable Archives: http://www.mail-archive.com/amradio@mailman.qth.net/ List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to amradio-requ...@mailman.qth.net with the word unsubscribe in the message body. __ Our Main Website: http://www.amfone.net AMRadio mailing list Searchable Archives: http://www.mail-archive.com/amradio@mailman.qth.net/ List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to amradio-requ...@mailman.qth.net with the word unsubscribe in the message body.
Re: [AMRadio] 160 meter antenna
What a terrific help you have been in posting this. Thanks Eddy. -- Original message from "Eddy Swynar" gswy...@durham.net: -- Hi Jim, When it comes to 160-meters, you must first assess just what, exactly, you want to accomplish on the band... Do you want to work just your Stateside buddies...? If so, a half-wave dipole / inverted "V" at 80' will be MORE than up to the task. Feed it with open wire line, coax, whatever... Do you just wanna work DX on the band...? Then delve into the various antenna handbooks to learn how to shunt feed that tower as a vertical. Eighty feet of "physical tower height" translates to some 120' of "electrical tower height" when fed the proper way (remember to add lotsa ground radials). Do you wanna work both domestic AND DX stations, both,on Topband...? Then string upan inverted "L" alongside your tower. The "mix" of both horizontal and vertical wire will be a good compromise in the matter of working bothnear-in, and far-away, stations...but again, be prepared to lay down some radial wires for it to work effectively. Radial wires are a whole 'nother topic, for sure... Anyway, that's my $0.02 worth...and I've been on the band, off on, almost from the time I first got licensed some 38 years ago. ~73~ Eddy VE3CUI - VE3XZ - Original Message - From: Jim Miller WB5OXQ in Waco To: Discussion of AM Radio in the Amateur Service Sent: Sunday, January 11, 2009 11:28 PM Subject: [AMRadio] 160 meter antenna I always wanted to try am on 160 but like most do not have enough room for a full size antenna, so, I am considering building a 160 meter antenna at our clubhouse because there is a 80' tower there and over an acre of land to spread out a 1/2 wave dipole. Question is; 1 Is a 1/2 wave wire dipole the best antenna for the band considering there isroom for it. 2 Is 80' high enough for the center of the inverted V? 3 How high do the ends need to be off of the ground? 4 Should I feed it with coax or ladder line to the 10' level (or other) then a balun to coax to the tuner (coax is the only acceptable line into the shack)? The shack is a metal building 30X60' and directly below the tower. There is no way to get ladder line to the operating position since all cables have to run through a 3" conduit for at least 30'. The tower is a free standing commercial tower made of 4 20' sections bolted together with a 2 meter and a 440mhz antenna at the top, all ham antennas. Thanks for any advice. Jim wb5oxq __Our Main Website: http://www.amfone.netAMRadio mailing listSearchable Archives: http://www.mail-archive.com/amradio@mailman.qth.net/List Rules (must read!): http://w5ami.net/amradiofaq.htmlList Home: http://mailman.qth.net/mailman/listinfo/amradioHelp: http://mailman.qth.net/mmfaq.htmlPost: mailto:AMRadio@mailman.qth.netTo unsubscribe, send an email to amradio-requ...@mailman.qth.net withthe word unsubscribe in the message body. __ Our Main Website: http://www.amfone.net AMRadio mailing list Searchable Archives: http://www.mail-archive.com/amradio@mailman.qth.net/ List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to amradio-requ...@mailman.qth.net with the word unsubscribe in the message body.
Re: [AMRadio] 160 meter antenna
Hi Robert, We have several of those wireless towers and monopoles around here, as well Those side wires are safety cables that climbers can clip on to with fall-arresting lanyards and harnesses, they are not radiators. Anyway, the folded unipole is a worthwhile antenna to try. I have had excellent results with an inverted L running up the side of my 80' tower and the horizontal portion sloping out to a tree. The L' perhaps looks more like a vee with one short leg. Total length is about 135 ft. I use a coil and capacitor parallel network at the base of the tower feeding the end of the antenna wire then coax back to the shack. As always, a good radial system really helps. 73, Jack, W9GT --- On Mon, 1/12/09, robertchar...@att.net robertchar...@att.net wrote: From: robertchar...@att.net robertchar...@att.net Subject: Re: [AMRadio] 160 meter antenna To: cozy...@yahoo.com, Discussion of AM Radio in the Amateur Service amradio@mailman.qth.net Date: Monday, January 12, 2009, 7:23 AM Neal. Thanks for the link on building the Unipole. I had worked for Sprint for some time and I noticed they were using that same concept on many of their towers. The link was exceptionally helpful -- Original message from neal Newman cozy...@yahoo.com: -- Jim you only need 50 feet of verticle space. why not just build yourself a Folded Unipole antenna if you Dont know how. Ask. its really easy. Just Run 3 lengths of #12 wire or if you have it #6 wire. short them up at around the 50 foot point and use 1 PVC Tubing as Insulators with clamps Down the side of the Tower. at the bottom Each wire is isolated with PVC from the Tower. BTW Each wire should be about 12 or more off the tower. then Tie all 3 wires together with a ring of #12 and take that as the Lead to the antenna tuner. Run at Least 4 ground radials 50 feet long If you can get the space make them 120 feet... and you will have a Killer 160 antenna. if not make an inverted L Run a wire thats 130 feet long. as far vertically as you can then run the rest out horizontally... again you need at least 4 ground radials the unipole is what we use for Broadcast stations when we are tight for height or space on a grounded Tower. Neal-KA2CAF CE- WTTM/WHWH/WJDM/WIBG/WFYL --- On Sun, 1/11/09, Jim Miller WB5OXQ in Waco wrote: From: Jim Miller WB5OXQ in Waco Subject: [AMRadio] 160 meter antenna To: Discussion of AM Radio in the Amateur Service Date: Sunday, January 11, 2009, 11:28 PM I always wanted to try am on 160 but like most do not have enough room for a full size antenna, so, I am considering building a 160 meter antenna at our clubhouse because there is a 80' tower there and over an acre of land to spread out a 1/2 wave dipole. Question is; 1 Is a 1/2 wave wire dipole the best antenna for the band considering there is room for it. 2 Is 80' high enough for the center of the inverted V? 3 How high do the ends need to be off of the ground? 4 Should I feed it with coax or ladder line to the 10' level (or other) then a balun to coax to the tuner (coax is the only acceptable line into the shack)? The shack is a metal building 30X60' and directly below the tower. There is no way to get ladder line to the operating position since all cables have to run through a 3 conduit for at least 30'. The tower is a free standing commercial tower made of 4 20' sections bolted together with a 2 meter and a 440mhz antenna at the top, all ham antennas. Thanks for any advice. Jim wb5oxq__ Our Main Website: http://www.amfone.net AMRadio mailing list Searchable Archives: http://www.mail-archive.com/amradio@mailman.qth.net/ List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to amradio-requ...@mailman.qth.net with the word unsubscribe in the message body. __ Our Main Website: http://www.amfone.net AMRadio mailing list Searchable Archives: http://www.mail-archive.com/amradio@mailman.qth.net/ List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to amradio-requ...@mailman.qth.net with the word unsubscribe in the message body. __ Our Main Website: http://www.amfone.net AMRadio mailing list Searchable Archives: http://www.mail-archive.com/amradio@mailman.qth.net/ List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman
Re: [AMRadio] 160 meter antenna
Hello Jack. I am familiar with the lynards that the climbers use as a safety line while climbing the tower. Their are however 3 vertical lines made out of what looks like guy wire with a circular ring near the base being fed by a box at the base. Just a FYI -- Original message from "JACK C. SHUTT" w...@verizon.net: -- Hi Robert, We have several of those wireless towers and monopoles around here, as well Those side wires are safety cables that climbers can clip on to with fall-arresting lanyards and harnesses, they are not radiators. Anyway, the folded unipole is a worthwhile antenna to try. I have had excellent results with an inverted L running up the side of my 80' tower and the "horizontal" portion sloping out to a tree. The "L' perhaps looks more like a vee with one short leg. Total length is about 135 ft. I use a coil and capacitor parallel network at the base of the tower feeding the end of the antenna wire then coax back to the shack. As always, a good radial system really helps. 73, Jack, W9GT--- On Mon, 1/12/09, robertchar...@att.net robertchar...@att.net wrote: From: robertchar...@att.net robertchar...@att.netSubject: Re: [AMRadio] 160 meter antennaTo: cozy...@yahoo.com, "Discussion of AM Radio in the Amateur Service" amradio@mailman.qth.netDate: Monday, January 12, 2009, 7:23 AM Neal. Thanks for the link on building the Unipole. I had worked for Sprint for some time and I noticed they were using that same concept on many of their towers. The link was exceptionally helpful -- Original message from neal Newman cozy...@yahoo.com: -- Jim you only need 50 feet of verticle space. why not just build yourself a Folded Unipole antenna if you Dont know how. Ask. its really easy. Just Run 3 lengths of #12 wire or if you have it #6 wire. short them up at around the 50 foot point and use 1" PVC Tubing as Insulators with clamps Down the side of the Tower. at the bottom Each wire is isolated with PVC from the Tower. BTW Each wire should be about 12" or more off the tower. then Tie all 3 wires together with a ring of #12 and take that as the Lead to the antenna tuner. Run at Least 4 ground radials 50 feet long If you can get the space make them 120 feet... and you will have a Killer 160 antenna. if not make an inverted L Run a wire thats 130 feet long. as far vertically as you can then run the rest out horizontally... again you need at least 4 ground radials the unipole is what we use for Broadcast stations when we are tight for height or space on a grounded Tower. Neal-KA2CAF CE- WTTM/WHWH/WJDM/WIBG/WFYL--- On Sun, 1/11/09, Jim Miller WB5OXQ in Waco wrote:From: Jim Miller WB5OXQ in Waco Subject: [AMRadio] 160 meter antenna To: "Discussion of AM Radio in the Amateur Service" Date: Sunday, January 11, 2009, 11:28 PM I always wanted to try am on 160 but like most do not have enough room for a full size antenna, so, I am considering building a 160 meter antenna at our clubhouse because there is a 80' tower there and over an acre of land to spread out a 1/2 wave dipole. Question is; 1 Is a 1/2 wave wire dipole the best antenna for the band considering there is room for it. 2 Is 80' high enough for the center of the inverted V? 3 How high do the ends need to be off of the ground? 4 Should I feed it with coax or ladder line to the 10' level (or other) then a balun to coax to the tuner (coax is the only acceptable line into the shack)? The shack is a metal building 30X60' and directly below the tower. There is no way to get ladder line to the operating position since all cables have to run through a 3" conduit for at least 30'. The tower is a free standing commercial tower made of 4 20' sections bolted together with a 2 meter and a 440mhz antenna at the top, all ham antennas. Thanks for any advice. Jim wb5oxq__ Our Main Website: http://www.amfone.net AMRadio mailing list Searchable Archives: http://www.mail-archive.com/amradio@mailman.qth.net/ List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to amradio-requ...@mailman.qth.net with the word unsubscribe in the message body. __ Our Main Website: http://www.amfone.net AMRadio mailing list Searchable Archives: http://www.mail-archive.com/amradio@mailman.qth.net/ List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to amradio-requ...@mailman.qth.net with the word unsubscribe in the message body.
Re: [AMRadio] 160 meter antenna
This is a skirt type antenna it's a fairly common trick used at some AM b'cast sites. This way the tower can be grounded rather than sitting on a base insulator. Bill AD5OL From: robertchar...@att.net robertchar...@att.net To: w...@verizon.net; Discussion of AM Radio in the Amateur Service amradio@mailman.qth.net Sent: Monday, January 12, 2009 12:13:42 PM Subject: Re: [AMRadio] 160 meter antenna Hello Jack. I am familiar with the lynards that the climbers use as a safety line while climbing the tower. Their are however 3 vertical lines made out of what looks like guy wire with a circular ring near the base being fed by a box at the base. Just a FYI -- Original message from JACK C. SHUTT w...@verizon.net: -- Hi Robert, We have several of those wireless towers and monopoles around here, as well Those side wires are safety cables that climbers can clip on to with fall-arresting lanyards and harnesses, they are not radiators. Anyway, the folded unipole is a worthwhile antenna to try. I have had excellent results with an inverted L running up the side of my 80' tower and the horizontal portion sloping out to a tree. The L' perhaps looks more like a vee with one short leg. Total length is about 135 ft. I use a coil and capacitor parallel network at the base of the tower feeding the end of the antenna wire then coax back to the shack. As always, a good radial system really helps. 73, Jack, W9GT --- On Mon, 1/12/09, robertchar...@att.net robertchar...@att.net wrote: From: robertchar...@att.net robertchar...@att.net Subject: Re: [AMRadio] 160 meter antenna To: cozy...@yahoo.com, Discussion of AM Radio in the Amateur Service amradio@mailman.qth.net Date: Monday, January 12, 2009, 7:23 AM Neal. Thanks for the link on building the Unipole. I had worked for Sprint for some time and I noticed they were using that same concept on many of their towers. The link was exceptionally helpful -- Original message from neal Newman cozy...@yahoo.com: -- Jim you only need 50 feet of verticle space. why not just build yourself a Folded Unipole antenna if you Dont know how. Ask. its really easy. Just Run 3 lengths of #12 wire or if you have it #6 wire. short them up at around the 50 foot point and use 1 PVC Tubing as Insulators with clamps Down the side of the Tower. at the bottom Each wire is isolated with PVC from the Tower. BTW Each wire should be about 12 or more off the tower. then Tie all 3 wires together with a ring of #12 and take that as the Lead to the antenna tuner. Run at Least 4 ground radials 50 feet long If you can get the space make them 120 feet... and you will have a Killer 160 antenna. if not make an inverted L Run a wire thats 130 feet long. as far vertically as you can then run the rest out horizontally... again you need at least 4 ground radials the unipole is what we use for Broadcast stations when we are tight for height or space on a grounded Tower. Neal-KA2CAF CE- WTTM/WHWH/WJDM/WIBG/WFYL --- On Sun, 1/11/09, Jim Miller WB5OXQ in Waco wrote: From: Jim Miller WB5OXQ in Waco Subject: [AMRadio] 160 meter antenna To: Discussion of AM Radio in the Amateur Service Date: Sunday, January 11, 2009, 11:28 PM I always wanted to try am on 160 but like most do not have enough room for a full size antenna, so, I am considering building a 160 meter antenna at our clubhouse because there is a 80' tower there and over an acre of land to spread out a 1/2 wave dipole. Question is; 1 Is a 1/2 wave wire dipole the best antenna for the band considering there is room for it. 2 Is 80' high enough for the center of the inverted V? 3 How high do the ends need to be off of the ground? 4 Should I feed it with coax or ladder line to the 10' level (or other) then a balun to coax to the tuner (coax is the only acceptable line into the shack)? The shack is a metal building 30X60' and directly below the tower. There is no way to get ladder line to the operating position since all cables have to run through a 3 conduit for at least 30'. The tower is a free standing commercial tower made of 4 20' sections bolted together with a 2 meter and a 440mhz antenna at the top, all ham antennas. Thanks for any advice. Jim wb5oxq__ Our Main Website: http://www.amfone.net AMRadio mailing list Searchable Archives: http://www.mail-archive.com/amradio@mailman.qth.net/ List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to amradio-requ...@mailman.qth.net with the word unsubscribe in the message body
Re: [AMRadio] 160 meter antenna
Bill, I wasn't aware the broadcast towers were sitting atop of a insulator on the base...is this considered the norm? What type of material would you suppose the insulator is made with? -- Original message from BILL GUYGER bguy...@sbcglobal.net: -- This is a skirt type antenna it's a fairly common "trick" used at someAM b'cast sites. This way the tower can be grounded rather than sitting on a base insulator. Bill AD5OL From: "robertchar...@att.net" <robertchar...@att.net>To: w...@verizon.net; Discussion of AM Radio in the Amateur Service <AMRADIO@MAILMAN.QTH.NET> Sent: Monday, January 12, 2009 12:13:42 PM Subject: Re: [AMRadio] 160 meter antenna Hello Jack. I am familiar with the lynards that the climbers use as a safety line while climbing the tower. Their are however 3 vertical lines made out of what looks like guy wire with a circular ring near the base being fed by a box at the base. Just a FYI -- Original message from "JACK C. SHUTT" <w...@verizon.net>: --Hi Robert, We have several of those wireless towers and monopoles around here, as well Those side wires are safety cables that climbers can clip on to with fall-arresting lanyards and harnesses, they are not radiators. Anyway, the folded unipole is a worthwhile antenna to try. I have had excellent results with an inverted L running up the side of my 80' tower and the "horizontal" portion sloping out to a tree. The "L' perhaps looks more like a vee with one short leg. Total length is about 135 ft. I use a coil and capacitor parallel network at the base of the tower feeding the end of the antenna wire then coax back to the shack. As always, a good radial system really helps. 73, Jack, W9GT --- On Mon, 1/12/09, robertchar...@att.net <robertchar...@att.net>wrote: From: robertchar...@att.net <robertchar...@att.net> Subject: Re: [AMRadio] 160 meter antenna To: cozy...@yahoo.com, "Discussion of AM Radio in the Amateur Service" <AMRADIO@MAILMAN.QTH.NET> Date: Monday, January 12, 2009, 7:23 AMNeal. Thanks for the link on building the Unipole. I had worked for Sprint for some time and I noticed they were using that same concept on many of their towers. The link was exceptionally helpful -- Original message from neal Newman <cozy...@yahoo.com>: -- Jim you only need 50 feet of verticle space. why not just build yourself a Folded Unipole antenna if you Dont know how. Ask. its really easy. Just Run 3 lengths of #12 wire or if you have it #6 wire. short them up at around the 50 foot point and use 1" PVC Tubing as Insulators with clamps Down the side of the Tower. at the bottom Each wire is isolated with PVC from the Tower. BTW Each wire should be about 12" or more off the tower. then Tie all 3 wires together with a ring of #12 and take that as the Lead to the antenna tuner. Run at Least 4 ground radials 50 feet long If you can get the space make them 120 feet... and you will have a Killer 160 antenna. if not make an inverted L Run a wire thats 130 feet long. as far vertically as you can then run the rest out horizontally... again you need at least 4 ground radials the unipole is what we use for Broadcast stations when we are tight for height or space on a grounded Tower. Neal-KA2CAF CE- WTTM/WHWH/WJDM/WIBG/WFYL --- On Sun, 1/11/09, Jim Miller WB5OXQ in Waco wrote: From: Jim Miller WB5OXQ in WacoSubject: [AMRadio] 160 meter antennaTo: "Discussion of AM Radio in the Amateur Service"Date: Sunday, January 11, 2009, 11:28 PMI always wanted to try am on 160 but like most do not haveenough room for a full size antenna, so,I am considering building a 160 meter antenna at ourclubhouse because there is a 80' tower there and over anacre of land to spread out a 1/2 wave dipole. Question is;1 Is a 1/2 wave wire dipole the best antenna for the bandconsidering there is room for it.2 Is 80' high enough for the center of the inverted V?3 How high do the ends need to be off of the ground?4 Should I feed it with coax or ladder line to the 10'level (or other) then a balun to coax to the tuner (coax isthe only acceptable line into the shack)? The shack is ametal building 30X60' and directly below the tower.There is no way to get ladder line to the operating positionsince all cables have to run through a 3" conduit forat least 30'. The tower is a free standing commercial tower made of 420' sections bolted together with a 2 meter and a 440mhzantenna at the top, all ham antennas. Thanks for any advice. Jimwb5oxq__Our Main Website: http://www.amfone.netAMRadio mailing listSearchable Archives:http
Re: [AMRadio] 160 meter antenna
At most AM sites the tower(s) is (are) the radiator(s) and usually base fed, but sometimes a shunt feed arrangement is used. The base insulator is ceramic, with the best types filled with oil. Electrical for tower lighting is fed across the base insulator with a ring transformer where the primary and secondary are interlocked rings set at 90 degrees to one another for minimum capacitance, or a lighting choke which is a bifilar wound solenoid choke with bypass caps on each end. The center tap of the capacitors on the tower end is referenced (bonded) to the tower, on the line end the center tap is grounded. Chokes are typically used on lower impedance towers, since they're a hell of a lot cheaper than the transformers. Bill From: robertchar...@att.net robertchar...@att.net To: Discussion of AM Radio in the Amateur Service amradio@mailman.qth.net Sent: Monday, January 12, 2009 2:36:00 PM Subject: Re: [AMRadio] 160 meter antenna Bill, I wasn't aware the broadcast towers were sitting atop of a insulator on the base...is this considered the norm? What type of material would you suppose the insulator is made with? -- Original message from BILL GUYGER bguy...@sbcglobal.net: -- This is a skirt type antenna it's a fairly common trick used at some AM b'cast sites. This way the tower can be grounded rather than sitting on a base insulator. Bill AD5OL From: robertchar...@att.net To: w...@verizon.net; Discussion of AM Radio in the Amateur Service Sent: Monday, January 12, 2009 12:13:42 PM Subject: Re: [AMRadio] 160 meter antenna Hello Jack. I am familiar with the lynards that the climbers use as a safety line while climbing the tower. Their are however 3 vertical lines made out of what looks like guy wire with a circular ring near the base being fed by a box at the base. Just a FYI -- Original message from JACK C. SHUTT : -- Hi Robert, We have several of those wireless towers and monopoles around here, as well Those side wires are safety cables that climbers can clip on to with fall-arresting lanyards and harnesses, they are not radiators. Anyway, the folded unipole is a worthwhile antenna to try. I have had excellent results with an inverted L running up the side of my 80' tower and the horizontal portion sloping out to a tree. The L' perhaps looks more like a vee with one short leg. Total length is about 135 ft. I use a coil and capacitor parallel network at the base of the tower feeding the end of the antenna wire then coax back to the shack. As always, a good radial system really helps. 73, Jack, W9GT --- On Mon, 1/12/09, robertchar...@att.net wrote: From: robertchar...@att.net Subject: Re: [AMRadio] 160 meter antenna To: cozy...@yahoo.com, Discussion of AM Radio in the Amateur Service Date: Monday, January 12, 2009, 7:23 AM Neal. Thanks for the link on building the Unipole. I had worked for Sprint for some time and I noticed they were using that same concept on many of their towers. The link was exceptionally helpful -- Original message from neal Newman : -- Jim you only need 50 feet of verticle space. why not just build yourself a Folded Unipole antenna if you Dont know how. Ask. its really easy. Just Run 3 lengths of #12 wire or if you have it #6 wire. short them up at around the 50 foot point and use 1 PVC Tubing as Insulators with clamps Down the side of the Tower. at the bottom Each wire is isolated with PVC from the Tower. BTW Each wire should be about 12 or more off the tower. then Tie all 3 wires together with a ring of #12 and take that as the Lead to the antenna tuner. Run at Least 4 ground radials 50 feet long If you can get the space make them 120 feet... and you will have a Killer 160 antenna. if not make an inverted L Run a wire thats 130 feet long. as far vertically as you can then run the rest out horizontally... again you need at least 4 ground radials the unipole is what we use for Broadcast stations when we are tight for height or space on a grounded Tower. Neal-KA2CAF CE- WTTM/WHWH/WJDM/WIBG/WFYL --- On Sun, 1/11/09, Jim Miller WB5OXQ in Waco wrote: From: Jim Miller WB5OXQ in Waco Subject: [AMRadio] 160 meter antenna To: Discussion of AM Radio in the Amateur Service Date: Sunday, January 11, 2009, 11:28 PM I always wanted to try am on 160 but like most do not have enough room for a full size antenna, so, I am considering building a 160 meter antenna at our clubhouse because there is a 80' tower there and over an acre of land to spread out a 1/2 wave dipole. Question is; 1 Is a 1/2 wave wire dipole the best antenna for the band considering there is room for it. 2 Is 80' high enough
Re: [AMRadio] 160 meter antenna
I would bet that the Skirt type antenna that you describe is actually a detuning system on a cellphone tower that is within two miles of a Directional AM Broadcast array. If the Cell tower is within the two mile range, the company who owns it must have a partial proof of performance done on the AM directional array before and after the tower is built. If it is shown to distort the pattern, then the detuning network that you see is added and tuned to make the cell tower invisible electrically to the AM array at the broadcast frequency. It actually is an untenna I guess. Ken Zuercher KC8QO --- On Mon, 1/12/09, robertchar...@att.net robertchar...@att.net wrote: From: robertchar...@att.net robertchar...@att.net Subject: Re: [AMRadio] 160 meter antenna To: Discussion of AM Radio in the Amateur Service amradio@mailman.qth.net Date: Monday, January 12, 2009, 3:36 PM Bill, I wasn't aware the broadcast towers were sitting atop of a insulator on the base...is this considered the norm? What type of material would you suppose the insulator is made with? -- Original message from BILL GUYGER bguy...@sbcglobal.net: -- This is a skirt type antenna it's a fairly common trick used at some AM b'cast sites. This way the tower can be grounded rather than sitting on a base insulator. Bill AD5OL From: robertchar...@att.net To: w...@verizon.net; Discussion of AM Radio in the Amateur Service Sent: Monday, January 12, 2009 12:13:42 PM Subject: Re: [AMRadio] 160 meter antenna Hello Jack. I am familiar with the lynards that the climbers use as a safety line while climbing the tower. Their are however 3 vertical lines made out of what looks like guy wire with a circular ring near the base being fed by a box at the base. Just a FYI -- Original message from JACK C. SHUTT : -- Hi Robert, We have several of those wireless towers and monopoles around here, as well Those side wires are safety cables that climbers can clip on to with fall-arresting lanyards and harnesses, they are not radiators. Anyway, the folded unipole is a worthwhile antenna to try. I have had excellent results with an inverted L running up the side of my 80' tower and the horizontal portion sloping out to a tree. The L' perhaps looks more like a vee with one short leg. Total length is about 135 ft. I use a coil and capacitor parallel network at the base of the tower feeding the end of the antenna wire then coax back to the shack. As always, a good radial system really helps. 73, Jack, W9GT --- On Mon, 1/12/09, robertchar...@att.net wrote: From: robertchar...@att.net Subject: Re: [AMRadio] 160 meter antenna To: cozy...@yahoo.com, Discussion of AM Radio in the Amateur Service Date: Monday, January 12, 2009, 7:23 AM Neal. Thanks for the link on building the Unipole. I had worked for Sprint for some time and I noticed they were using that same concept on many of their towers. The link was exceptionally helpful -- Original message from neal Newman : -- Jim you only need 50 feet of verticle space. why not just build yourself a Folded Unipole antenna if you Dont know how. Ask. its really easy. Just Run 3 lengths of #12 wire or if you have it #6 wire. short them up at around the 50 foot point and use 1 PVC Tubing as Insulators with clamps Down the side of the Tower. at the bottom Each wire is isolated with PVC from the Tower. BTW Each wire should be about 12 or more off the tower. then Tie all 3 wires together with a ring of #12 and take that as the Lead to the antenna tuner. Run at Least 4 ground radials 50 feet long If you can get the space make them 120 feet... and you will have a Killer 160 antenna. if not make an inverted L Run a wire thats 130 feet long. as far vertically as you can then run the rest out horizontally... again you need at least 4 ground radials the unipole is what we use for Broadcast stations when we are tight for height or space on a grounded Tower. Neal-KA2CAF CE- WTTM/WHWH/WJDM/WIBG/WFYL --- On Sun, 1/11/09, Jim Miller WB5OXQ in Waco wrote: From: Jim Miller WB5OXQ in Waco Subject: [AMRadio] 160 meter antenna To: Discussion of AM Radio in the Amateur Service Date: Sunday, January 11, 2009, 11:28 PM I always wanted to try am on 160 but like most do not have enough room for a full size antenna, so, I am considering building a 160 meter antenna at our clubhouse because there is a 80' tower there and over an acre of land to spread out a 1/2 wave dipole. Question is; 1 Is a 1/2 wave wire dipole the best antenna for the band considering there is room for it. 2 Is 80' high enough for the center
Re: [AMRadio] 160 meter antenna
If you run any power at all, forget the balun unless you gat some sort of monster one, the usual suspects wont work for even moderate power AM. Any time I tried traps or baluns on AM, all I got was a fire. Some might take 50 watts carrier, but the DX100 blew out many a trap back when I was starting out in AM. Brett N2DTS - Original Message - From: Jim Miller WB5OXQ in Waco To: Discussion of AM Radio in the Amateur Service Sent: Sunday, January 11, 2009 11:28 PM Subject: [AMRadio] 160 meter antenna I always wanted to try am on 160 but like most do not have enough room for a full size antenna, so, I am considering building a 160 meter antenna at our clubhouse because there is a 80' tower there and over an acre of land to spread out a 1/2 wave dipole. Question is; 1 Is a 1/2 wave wire dipole the best antenna for the band considering there is room for it. 2 Is 80' high enough for the center of the inverted V? 3 How high do the ends need to be off of the ground? 4 Should I feed it with coax or ladder line to the 10' level (or other) then a balun to coax to the tuner (coax is the only acceptable line into the shack)? The shack is a metal building 30X60' and directly below the tower. There is no way to get ladder line to the operating position since all cables have to run through a 3 conduit for at least 30'. The tower is a free standing commercial tower made of 4 20' sections bolted together with a 2 meter and a 440mhz antenna at the top, all ham antennas. Thanks for any advice. Jim wb5oxq -- __ Our Main Website: http://www.amfone.net AMRadio mailing list Searchable Archives: http://www.mail-archive.com/amradio@mailman.qth.net/ List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to amradio-requ...@mailman.qth.net with the word unsubscribe in the message body.__ Our Main Website: http://www.amfone.net AMRadio mailing list Searchable Archives: http://www.mail-archive.com/amradio@mailman.qth.net/ List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to amradio-requ...@mailman.qth.net with the word unsubscribe in the message body.
Re: [AMRadio] 160 meter antenna
Very interesting! How about a AT4K tuner by Palstar in the shack to tune the antenna? -- Original message from "Brett Gazdzinski" brett.gazdzin...@verizon.net: -- If you run any power at all, forget the balun unless you gat some sort of monster one, the usual suspects wont work foreven moderate powerAM. Any time I tried traps or baluns on AM, all I got was a fire. Some might take 50 watts carrier, but the DX100 blew out many a trap back when I was starting out in AM. Brett N2DTS - Original Message - From: Jim Miller WB5OXQ in Waco To: Discussion of AM Radio in the Amateur Service Sent: Sunday, January 11, 2009 11:28 PM Subject: [AMRadio] 160 meter antenna I always wanted to try am on 160 but like most do not have enough room for a full size antenna, so, I am considering building a 160 meter antenna at our clubhouse because there is a 80' tower there and over an acre of land to spread out a 1/2 wave dipole. Question is; 1 Is a 1/2 wave wire dipole the best antenna for the band considering there isroom for it. 2 Is 80' high enough for the center of the inverted V? 3 How high do the ends need to be off of the ground? 4 Should I feed it with coax or ladder line to the 10' level (or other) then a balun to coax to the tuner (coax is the only acceptable line into the shack)? The shack is a metal building 30X60' and directly below the tower. There is no way to get ladder line to the operating position since all cables have to run through a 3" conduit for at least 30'. The tower is a free standing commercial tower made of 4 20' sections bolted together with a 2 meter and a 440mhz antenna at the top, all ham antennas. Thanks for any advice. Jim wb5oxq __Our Main Website: http://www.amfone.netAMRadio mailing listSearchable Archives: http://www.mail-archive.com/amradio@mailman.qth.net/List Rules (must read!): http://w5ami.net/amradiofaq.htmlList Home: http://mailman.qth.net/mailman/listinfo/amradioHelp: http://mailman.qth.net/mmfaq.htmlPost: mailto:AMRadio@mailman.qth.netTo unsubscribe, send an email to amradio-requ...@mailman.qth.net withthe word unsubscribe in the message body. __ Our Main Website: http://www.amfone.net AMRadio mailing list Searchable Archives: http://www.mail-archive.com/amradio@mailman.qth.net/ List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to amradio-requ...@mailman.qth.net with the word unsubscribe in the message body.
Re: [AMRadio] 160 meter antenna
Remember what balun means, balanced to unbalanced. This is not some magic device to withstand grand excursion from center frequency of an antenna. It is to transform on impedance to another. If you move far enough off center you can wind up with very high voltage in the balun, resulting in what Brett describes. Probably the best balun for high power is the choke balun wound on 6 PVC of RG 8U or the beads that fit over the coax. Since supporting the choke balun at the center of my antenna would be a challenge, I use the beads. There are there to prevent current of the shield of my coax feedline when I am far off center frequency of the antenna. If you are going to move more than 3% of frequency, then forget the W2AU or, even, the so called quality type of balun. The W2AU I took apart was constructed of RG 58. Not the best for a HV environment. When you move from one end of the band to the other, just use a good high power tuner and be prepared for lost power in the tuner. Jim/W5JO - Original Message - If you run any power at all, forget the balun unless you gat some sort of monster one, the usual suspects wont work for even moderate power AM. Any time I tried traps or baluns on AM, all I got was a fire. Some might take 50 watts carrier, but the DX100 blew out many a trap back when I was starting out in AM. Brett N2DTS__ Our Main Website: http://www.amfone.net AMRadio mailing list Searchable Archives: http://www.mail-archive.com/amradio@mailman.qth.net/ List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to amradio-requ...@mailman.qth.net with the word unsubscribe in the message body.
Re: [AMRadio] 160 meter antenna
Brett Gazdzinski wrote: If you run any power at all, forget the balun unless you gat some sort of monster one, the usual suspects wont work for even moderate power AM. Got that right! I arced-over the little LDG balun on my ladder line fed dipole the first time I keyed up my T-368. I should have remembered, but it had been OK with the 100 watt class AM rigs I ran before. The balun that's built-into the Heath 2060A tuner I'm using now seems to work fine at high power, but it's about 4 times the size. 73, Bob W9RAN __ Our Main Website: http://www.amfone.net AMRadio mailing list Searchable Archives: http://www.mail-archive.com/amradio@mailman.qth.net/ List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to amradio-requ...@mailman.qth.net with the word unsubscribe in the message body.
Re: [AMRadio] 160 meter antenna
I have heard ferrite type stuff can cause nasty problems at high power. Since I run tube rigs, I think I will just cut a dipole for the center of 80 meters, and ditch the tuner, which gets quite warm on the G5RV. If I am going to heat something up, it might be better that its not in a shielded metal box. While a balanced setup is best, I don't want to have to tune the antenna every time I change frequencies, as I like to hop around between bands and the phone and CW parts of the bands.. Without a tuner, you can use the antenna's on receive, even on other bands, while with a tuner, if you get far from where you are tuned from, you get a lot of loss... Brett - Original Message - From: Jim Wilhite To: Discussion of AM Radio in the Amateur Service Sent: Monday, January 12, 2009 6:46 PM Subject: Re: [AMRadio] 160 meter antenna Remember what balun means, balanced to unbalanced. This is not some magic device to withstand grand excursion from center frequency of an antenna. It is to transform on impedance to another. If you move far enough off center you can wind up with very high voltage in the balun, resulting in what Brett describes. Probably the best balun for high power is the choke balun wound on 6 PVC of RG 8U or the beads that fit over the coax. Since supporting the choke balun at the center of my antenna would be a challenge, I use the beads. There are there to prevent current of the shield of my coax feedline when I am far off center frequency of the antenna. If you are going to move more than 3% of frequency, then forget the W2AU or, even, the so called quality type of balun. The W2AU I took apart was constructed of RG 58. Not the best for a HV environment. When you move from one end of the band to the other, just use a good high power tuner and be prepared for lost power in the tuner. Jim/W5JO - Original Message - If you run any power at all, forget the balun unless you gat some sort of monster one, the usual suspects wont work for even moderate power AM. Any time I tried traps or baluns on AM, all I got was a fire. Some might take 50 watts carrier, but the DX100 blew out many a trap back when I was starting out in AM. Brett N2DTS -- __ Our Main Website: http://www.amfone.net AMRadio mailing list Searchable Archives: http://www.mail-archive.com/amradio@mailman.qth.net/ List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to amradio-requ...@mailman.qth.net with the word unsubscribe in the message body.__ Our Main Website: http://www.amfone.net AMRadio mailing list Searchable Archives: http://www.mail-archive.com/amradio@mailman.qth.net/ List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to amradio-requ...@mailman.qth.net with the word unsubscribe in the message body.
Re: [AMRadio] 160 meter antenna
I have also seen some tuned skirts that are tuned to another stations frequency to isolate the tower to prevent mixing and causing intermod. Sure wish the 3 principal stations in my fair city would tune their skirts !! Charlie, K0NG __ Our Main Website: http://www.amfone.net AMRadio mailing list Searchable Archives: http://www.mail-archive.com/amradio@mailman.qth.net/ List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to amradio-requ...@mailman.qth.net with the word unsubscribe in the message body.
Re: [AMRadio] 160 meter antenna
Yes Ken you are correct about the detuning skirt. In fact mono pole here has a detuning skirt around the tower. I am also familiar with the climbing safety lines. You can tell the difference in that most detuning skirts I have seen on Cell mono poles had several wires around the pole coming down. Also you will see quite a bit of insulators and hardware compared to a simple safety line. However that last time I was there the fiberglass housing the vacuum capacitor had been damaged by hail. So it was full of water. Very sad deal. However I don't think they need it any more. The AM station was right next to this moved across the river. After they put on the mono pole it caused a problem with the AM station's pattern. So up went the detuning skirt that looks much like the Folder Unipoles, hi. 73 de jay/w5jay.. I would bet that the Skirt type antenna that you describe is actually a detuning system on a cellphone tower that is within two miles of a Directional AM Broadcast array. If the Cell tower is within the two mile range, the company who owns it must have a partial proof of performance done on the AM directional array before and after the tower is built. If it is shown to distort the pattern, then the detuning network that you see is added and tuned to make the cell tower invisible electrically to the AM array at the broadcast frequency. It actually is an untenna I guess. Ken Zuercher KC8QO --- On Mon, 1/12/09, robertchar...@att.net robertchar...@att.net wrote: From: robertchar...@att.net robertchar...@att.net Subject: Re: [AMRadio] 160 meter antenna To: Discussion of AM Radio in the Amateur Service amradio@mailman.qth.net Date: Monday, January 12, 2009, 3:36 PM Bill, I wasn't aware the broadcast towers were sitting atop of a insulator on the base...is this considered the norm? What type of material would you suppose the insulator is made with? -- Original message from BILL GUYGER bguy...@sbcglobal.net: -- This is a skirt type antenna it's a fairly common trick used at some AM b'cast sites. This way the tower can be grounded rather than sitting on a base insulator. Bill AD5OL From: robertchar...@att.net To: w...@verizon.net; Discussion of AM Radio in the Amateur Service Sent: Monday, January 12, 2009 12:13:42 PM Subject: Re: [AMRadio] 160 meter antenna Hello Jack. I am familiar with the lynards that the climbers use as a safety line while climbing the tower. Their are however 3 vertical lines made out of what looks like guy wire with a circular ring near the base being fed by a box at the base. Just a FYI -- Original message from JACK C. SHUTT : -- Hi Robert, We have several of those wireless towers and monopoles around here, as well Those side wires are safety cables that climbers can clip on to with fall-arresting lanyards and harnesses, they are not radiators. Anyway, the folded unipole is a worthwhile antenna to try. I have had excellent results with an inverted L running up the side of my 80' tower and the horizontal portion sloping out to a tree. The L' perhaps looks more like a vee with one short leg. Total length is about 135 ft. I use a coil and capacitor parallel network at the base of the tower feeding the end of the antenna wire then coax back to the shack. As always, a good radial system really helps. 73, Jack, W9GT --- On Mon, 1/12/09, robertchar...@att.net wrote: From: robertchar...@att.net Subject: Re: [AMRadio] 160 meter antenna To: cozy...@yahoo.com, Discussion of AM Radio in the Amateur Service Date: Monday, January 12, 2009, 7:23 AM Neal. Thanks for the link on building the Unipole. I had worked for Sprint for some time and I noticed they were using that same concept on many of their towers. The link was exceptionally helpful -- Original message from neal Newman : -- Jim you only need 50 feet of verticle space. why not just build yourself a Folded Unipole antenna if you Dont know how. Ask. its really easy. Just Run 3 lengths of #12 wire or if you have it #6 wire. short them up at around the 50 foot point and use 1 PVC Tubing as Insulators with clamps Down the side of the Tower. at the bottom Each wire is isolated with PVC from the Tower. BTW Each wire should be about 12 or more off the tower. then Tie all 3 wires together with a ring of #12 and take that as the Lead to the antenna tuner. Run at Least 4 ground radials 50 feet long If you can get the space make them 120 feet... and you will have a Killer 160 antenna. if not make an inverted L Run a wire thats 130 feet long. as far vertically as you can then run the rest out horizontally... again you need at least 4 ground radials the unipole is what we use for Broadcast stations when we are tight for height
Re: [AMRadio] 160 Meter Antenna
A decent limited space 160 antenna for me has been a loaded inverted vee. See the description online at http://www.wd8das.net/160loadedvee.jpg It seems to actually work well for both local/regional and more distant contacts. I'm in Wisconsin and am able to work well the locals and around the state and adjacent states, as well as out to Ohio, Pennsylvania and south to Alabama. Steve WD8DAS sbjohns...@aol.com http://www.wd8das.net/ - Radio is your best entertainment value. - -Original Message- From: Thomas F. Giella KN4LF kn...@earthlink.net To: am radio QTH amradio@mailman.qth.net Sent: Mon, 12 Jan 2009 9:58 am Subject: [AMRadio] 160 Meter Antenna Jim, It all depends what you want to accomplish on 160 meters. An inverted V with a feedpoint at 80 feet above ground will be an NVIS 90 degree TOA antenna which will allow for rag chewing out to approximately 500 miles. As an inverted V the ends should be high enough so that a animals and people can't run into them. Also high enough so that at the feedpoint the wires are no closer than 90-120 degrees apart from each other to prevent RF signal cancellation. If you feed the inverted V with coax you may see a bandwidth of approximately 50 kc. You can then use a tee network antenna tuner to fool your rig or linear amplifier so as to be able to operate across more of the band with some loss. With window line and a balanced link coupled antenna tuner you can operate across all 200 kc of the band with virtually no loss. I use 300 ohm window line on my 160-10 meter full wave horizontal loop and bring it into the radio shack via a piece of 1 x 4 oak board with banana jacks through it. You want to keep the window line at least twice it's width away from metal to reduce interaction, so running it through metal conduit and parallel to other feed lines would not be good. A good compromise antenna for DXing and rag chewing is the 1/4 wave inverted L. I have a website on the 1/4 wave inverted L at http://www.kn4lf.com/kn4lf97.htm . 73 GUD DX, Thomas F. Giella, KN4LF Lakeland, FL, USA kn...@arrl.net KN4LF Amateur SWL Radio Autobiography: http://www.kn4lf.com __ Our Main Website: http://www.amfone.net AMRadio mailing list Searchable Archives: http://www.mail-archive.com/amradio@mailman.qth.net/ List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to amradio-requ...@mailman.qth.net with the word unsubscribe in the message body. __ Our Main Website: http://www.amfone.net AMRadio mailing list Searchable Archives: http://www.mail-archive.com/amradio@mailman.qth.net/ List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to amradio-requ...@mailman.qth.net with the word unsubscribe in the message body.
Re: [AMRadio] 160 meter antenna
Jim you only need 50 feet of verticle space. why not just build yourself a Folded Unipole antenna if you Dont know how. Ask. its really easy. Just Run 3 lengths of #12 wire or if you have it #6 wire. short them up at around the 50 foot point and use 1 PVC Tubing as Insulators with clamps Down the side of the Tower. at the bottom Each wire is isolated with PVC from the Tower. BTW Each wire should be about 12 or more off the tower. then Tie all 3 wires together with a ring of #12 and take that as the Lead to the antenna tuner. Run at Least 4 ground radials 50 feet long If you can get the space make them 120 feet... and you will have a Killer 160 antenna. if not make an inverted L Run a wire thats 130 feet long. as far vertically as you can then run the rest out horizontally... again you need at least 4 ground radials the unipole is what we use for Broadcast stations when we are tight for height or space on a grounded Tower. Neal-KA2CAF CE- WTTM/WHWH/WJDM/WIBG/WFYL --- On Sun, 1/11/09, Jim Miller WB5OXQ in Waco wb5...@grandecom.net wrote: From: Jim Miller WB5OXQ in Waco wb5...@grandecom.net Subject: [AMRadio] 160 meter antenna To: Discussion of AM Radio in the Amateur Service amradio@mailman.qth.net Date: Sunday, January 11, 2009, 11:28 PM I always wanted to try am on 160 but like most do not have enough room for a full size antenna, so, I am considering building a 160 meter antenna at our clubhouse because there is a 80' tower there and over an acre of land to spread out a 1/2 wave dipole. Question is; 1 Is a 1/2 wave wire dipole the best antenna for the band considering there is room for it. 2 Is 80' high enough for the center of the inverted V? 3 How high do the ends need to be off of the ground? 4 Should I feed it with coax or ladder line to the 10' level (or other) then a balun to coax to the tuner (coax is the only acceptable line into the shack)? The shack is a metal building 30X60' and directly below the tower. There is no way to get ladder line to the operating position since all cables have to run through a 3 conduit for at least 30'. The tower is a free standing commercial tower made of 4 20' sections bolted together with a 2 meter and a 440mhz antenna at the top, all ham antennas. Thanks for any advice. Jim wb5oxq__ Our Main Website: http://www.amfone.net AMRadio mailing list Searchable Archives: http://www.mail-archive.com/amradio@mailman.qth.net/ List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to amradio-requ...@mailman.qth.net with the word unsubscribe in the message body. __ Our Main Website: http://www.amfone.net AMRadio mailing list Searchable Archives: http://www.mail-archive.com/amradio@mailman.qth.net/ List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to amradio-requ...@mailman.qth.net with the word unsubscribe in the message body.
Re: [AMRadio] 160 meter antenna
Jim here is a link about folded unipole... just to give you an idea http://radiomagonline.com/mag/radio_folded_unipole/ Neal-ka2caf __ Our Main Website: http://www.amfone.net AMRadio mailing list Searchable Archives: http://www.mail-archive.com/amradio@mailman.qth.net/ List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to amradio-requ...@mailman.qth.net with the word unsubscribe in the message body.