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antenna suggestion
My primary antenna is a 33 ft folded dipole made from 300 ohm twin lead and
is mounted in my roof. It is coupled by a 300 to 75 ohm tv transformer to 75 ohm coax. The antenna is described in message 2471 of the Yahoo Rx-320 group and works fairly well. Recently, I acquired 3 rolls (40 ft each) of indoor 300 ohm coax, a closeout at Radio Shack. On checking my house diagram (drawing), I determined that I could run another antenna which could run about 100 feet if I include my garage. This is measured from left rear roof, through a wall, diagonally to front right garage (plus a 20 ft wrap on each end). I'd welcome any suggestions from the group on an antenna configuration such as dipole, folded dipole, twinlead converted to long wire (doubled back on itself), etc. This would be for SW reception, but MW would be a plus. Thanks. HankG |
In article ,
"HankG" no_one@invalid wrote: My primary antenna is a 33 ft folded dipole made from 300 ohm twin lead and is mounted in my roof. It is coupled by a 300 to 75 ohm tv transformer to 75 ohm coax. The antenna is described in message 2471 of the Yahoo Rx-320 group and works fairly well. Recently, I acquired 3 rolls (40 ft each) of indoor 300 ohm coax, a closeout at Radio Shack. On checking my house diagram (drawing), I determined that I could run another antenna which could run about 100 feet if I include my garage. This is measured from left rear roof, through a wall, diagonally to front right garage (plus a 20 ft wrap on each end). I'd welcome any suggestions from the group on an antenna configuration such as dipole, folded dipole, twinlead converted to long wire (doubled back on itself), etc. This would be for SW reception, but MW would be a plus. Thanks. You could take two of those 40 foot pieces and make a 80 foot folded dipole antenna. Some of the Radio Shack 300 / 75 ohm transformers are not much good below 10MHz. -- Telamon Ventura, California |
"Telamon" wrote in message ... In article , "HankG" no_one@invalid wrote: My primary antenna is a 33 ft folded dipole made from 300 ohm twin lead and is mounted in my roof. It is coupled by a 300 to 75 ohm tv transformer to 75 ohm coax. The antenna is described in message 2471 of the Yahoo Rx-320 group and works fairly well. Recently, I acquired 3 rolls (40 ft each) of indoor 300 ohm coax, a closeout at Radio Shack. On checking my house diagram (drawing), I determined that I could run another antenna which could run about 100 feet if I include my garage. This is measured from left rear roof, through a wall, diagonally to front right garage (plus a 20 ft wrap on each end). I'd welcome any suggestions from the group on an antenna configuration such as dipole, folded dipole, twinlead converted to long wire (doubled back on itself), etc. This would be for SW reception, but MW would be a plus. Thanks. You could take two of those 40 foot pieces and make a 80 foot folded dipole antenna. Yes. The resonant frequency of an (un)folded dipole of 80 ft would be about 5.85 Mhz. My current antenna (resonant at 14.18 Mhz) uses a twinlead stub which supposedly confers a broader bandwidth. I have used it to monitor 160 meters and works fairly well in the single digits. Is there a formula for calculating stub length to give this 80 footer greater bandwidth? Some of the Radio Shack 300 / 75 ohm transformers are not much good below 10MHz. Interestingly, I acquired the transformers (2 on a card) at the local dollar store. Works fine. HankG |
In article ,
"HankG" no_one@invalid wrote: "Telamon" wrote in message .. . In article , "HankG" no_one@invalid wrote: My primary antenna is a 33 ft folded dipole made from 300 ohm twin lead and is mounted in my roof. It is coupled by a 300 to 75 ohm tv transformer to 75 ohm coax. The antenna is described in message 2471 of the Yahoo Rx-320 group and works fairly well. Recently, I acquired 3 rolls (40 ft each) of indoor 300 ohm coax, a closeout at Radio Shack. On checking my house diagram (drawing), I determined that I could run another antenna which could run about 100 feet if I include my garage. This is measured from left rear roof, through a wall, diagonally to front right garage (plus a 20 ft wrap on each end). I'd welcome any suggestions from the group on an antenna configuration such as dipole, folded dipole, twinlead converted to long wire (doubled back on itself), etc. This would be for SW reception, but MW would be a plus. Thanks. You could take two of those 40 foot pieces and make a 80 foot folded dipole antenna. Yes. The resonant frequency of an (un)folded dipole of 80 ft would be about 5.85 Mhz. My current antenna (resonant at 14.18 Mhz) uses a twinlead stub which supposedly confers a broader bandwidth. I have used it to monitor 160 meters and works fairly well in the single digits. Is there a formula for calculating stub length to give this 80 footer greater bandwidth? According to a Joe Carr antenna book I have this: In meters A - 141.8 / F MHz - Over all length or distance between outer shorts B - 122 / F MHz - distance between inner shorts In addition you could leave the outer shorts open then it would be: A - 142 / F MHz - Over all length or distance between outer ends B - 122 / F MHz - distance between inner shorts Example for 9.75 MHz is A = 14.56 meters B = 12.51 meters Some of the Radio Shack 300 / 75 ohm transformers are not much good below 10MHz. Interestingly, I acquired the transformers (2 on a card) at the local dollar store. Works fine. Well, it depends on which one you got your hands on. On some the S21 falls off below 10MHz and you were talking about a lower frequency antenna so just watch out for that. -- Telamon Ventura, California |
"Telamon" wrote in message ... In article , "HankG" no_one@invalid wrote: "Telamon" wrote in message .. . In article , "HankG" no_one@invalid wrote: My primary antenna is a 33 ft folded dipole made from 300 ohm twin lead and is mounted in my roof. It is coupled by a 300 to 75 ohm tv transformer to 75 ohm coax. The antenna is described in message 2471 of the Yahoo Rx-320 group and works fairly well. Recently, I acquired 3 rolls (40 ft each) of indoor 300 ohm coax, a closeout at Radio Shack. On checking my house diagram (drawing), I determined that I could run another antenna which could run about 100 feet if I include my garage. This is measured from left rear roof, through a wall, diagonally to front right garage (plus a 20 ft wrap on each end). I'd welcome any suggestions from the group on an antenna configuration such as dipole, folded dipole, twinlead converted to long wire (doubled back on itself), etc. This would be for SW reception, but MW would be a plus. Thanks. You could take two of those 40 foot pieces and make a 80 foot folded dipole antenna. Yes. The resonant frequency of an (un)folded dipole of 80 ft would be about 5.85 Mhz. My current antenna (resonant at 14.18 Mhz) uses a twinlead stub which supposedly confers a broader bandwidth. I have used it to monitor 160 meters and works fairly well in the single digits. Is there a formula for calculating stub length to give this 80 footer greater bandwidth? According to a Joe Carr antenna book I have this: In meters A - 141.8 / F MHz - Over all length or distance between outer shorts B - 122 / F MHz - distance between inner shorts In addition you could leave the outer shorts open then it would be: A - 142 / F MHz - Over all length or distance between outer ends B - 122 / F MHz - distance between inner shorts Example for 9.75 MHz is A = 14.56 meters B = 12.51 meters Some of the Radio Shack 300 / 75 ohm transformers are not much good below 10MHz. Interestingly, I acquired the transformers (2 on a card) at the local dollar store. Works fine. Well, it depends on which one you got your hands on. On some the S21 falls off below 10MHz and you were talking about a lower frequency antenna so just watch out for that. What is meant by inner and outer 'shorts'? HankG |
HankG wrote: "Telamon" wrote in message ... In article , "HankG" no_one@invalid wrote: "Telamon" wrote in message .. . In article , "HankG" no_one@invalid wrote: My primary antenna is a 33 ft folded dipole made from 300 ohm twin lead and is mounted in my roof. It is coupled by a 300 to 75 ohm tv transformer to 75 ohm coax. The antenna is described in message 2471 of the Yahoo Rx-320 group and works fairly well. Recently, I acquired 3 rolls (40 ft each) of indoor 300 ohm coax, a closeout at Radio Shack. On checking my house diagram (drawing), I determined that I could run another antenna which could run about 100 feet if I include my garage. This is measured from left rear roof, through a wall, diagonally to front right garage (plus a 20 ft wrap on each end). I'd welcome any suggestions from the group on an antenna configuration such as dipole, folded dipole, twinlead converted to long wire (doubled back on itself), etc. This would be for SW reception, but MW would be a plus. Thanks. You could take two of those 40 foot pieces and make a 80 foot folded dipole antenna. Yes. The resonant frequency of an (un)folded dipole of 80 ft would be about 5.85 Mhz. My current antenna (resonant at 14.18 Mhz) uses a twinlead stub which supposedly confers a broader bandwidth. I have used it to monitor 160 meters and works fairly well in the single digits. Is there a formula for calculating stub length to give this 80 footer greater bandwidth? According to a Joe Carr antenna book I have this: In meters A - 141.8 / F MHz - Over all length or distance between outer shorts B - 122 / F MHz - distance between inner shorts In addition you could leave the outer shorts open then it would be: A - 142 / F MHz - Over all length or distance between outer ends B - 122 / F MHz - distance between inner shorts Example for 9.75 MHz is A = 14.56 meters B = 12.51 meters Some of the Radio Shack 300 / 75 ohm transformers are not much good below 10MHz. Interestingly, I acquired the transformers (2 on a card) at the local dollar store. Works fine. Well, it depends on which one you got your hands on. On some the S21 falls off below 10MHz and you were talking about a lower frequency antenna so just watch out for that. What is meant by inner and outer 'shorts'? Well, I guess you've never seen some of those kids running around the 'hood'. Some of them wear their shorts on the inside, some of them wear them on the outside. dxAce Michigan USA |
"HankG" no_one@invalid wrote in message ...
My primary antenna is a 33 ft folded dipole made from 300 ohm twin lead and is mounted in my roof. It is coupled by a 300 to 75 ohm tv transformer to 75 ohm coax. The antenna is described in message 2471 of the Yahoo Rx-320 group and works fairly well. Recently, I acquired 3 rolls (40 ft each) of indoor 300 ohm coax, a closeout at Radio Shack. On checking my house diagram (drawing), I determined that I could run another antenna which could run about 100 feet if I include my garage. This is measured from left rear roof, through a wall, diagonally to front right garage (plus a 20 ft wrap on each end). I'd welcome any suggestions from the group on an antenna configuration such as dipole, folded dipole, twinlead converted to long wire (doubled back on itself), etc. This would be for SW reception, but MW would be a plus. Thanks. HankG Forget about using the 300 ohm coax. Do yourself a favor if you want good receiving antenna. Go to Home Depot and purchase a roll of 14 gauge insulated wire, some screw-type eye bolts and two copper plating ground rods and quad shielded RG-6 coax. Then build an EWE antenna. It is one of the quietest antenna you can construct. And has fantastic results. Check the web for them. BW |
What is meant by inner and outer 'shorts'?
Well, I guess you've never seen some of those kids running around the 'hood'. Some of them wear their shorts on the inside, some of them wear them on the outside. lol! -Brian /lives in the hood |
"B Williams" wrote in message om... "HankG" no_one@invalid wrote in message ... My primary antenna is a 33 ft folded dipole made from 300 ohm twin lead and is mounted in my roof. It is coupled by a 300 to 75 ohm tv transformer to 75 ohm coax. The antenna is described in message 2471 of the Yahoo Rx-320 group and works fairly well. Recently, I acquired 3 rolls (40 ft each) of indoor 300 ohm coax, a closeout at Radio Shack. On checking my house diagram (drawing), I determined that I could run another antenna which could run about 100 feet if I include my garage. This is measured from left rear roof, through a wall, diagonally to front right garage (plus a 20 ft wrap on each end). I'd welcome any suggestions from the group on an antenna configuration such as dipole, folded dipole, twinlead converted to long wire (doubled back on itself), etc. This would be for SW reception, but MW would be a plus. Thanks. HankG Forget about using the 300 ohm coax. Do yourself a favor if you want good receiving antenna. Go to Home Depot and purchase a roll of 14 gauge insulated wire, some screw-type eye bolts and two copper plating ground rods and quad shielded RG-6 coax. Then build an EWE antenna. It is one of the quietest antenna you can construct. And has fantastic results. Check the web for them. On your suggestion, I've started to do some investigating of EWE antennas. My (land) plot may not be the best. What I've read so far, seems to suggest that EWEs are more or less confined to 1 or 2 bands. I need something that is broadband (HF); MW and LW would be a plus. (dream on?). Is there such a thing as a broadband EWE? HankG |
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