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#1
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Dipole Antenna Question
If I use a Budwig Dipole Center Insulator
(http://www.k1cra.com/images/products/original/299.jpg) for my random length long wire antenna, should the length of the wire coming off each side of the center insulator be equal? My yard will allow me to have one side of the insulator about 200 feet long and the other side only about 50 feet. Should I even mess with the center insulator and just go with a random length of wire? I am just running this into a DX398 for occasional shortwave listening. Thanks. |
#2
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Dipole Antenna Question
DJ wrote: If I use a Budwig Dipole Center Insulator (http://www.k1cra.com/images/products/original/299.jpg) for my random length long wire antenna, should the length of the wire coming off each side of the center insulator be equal? My yard will allow me to have one side of the insulator about 200 feet long and the other side only about 50 feet. Should I even mess with the center insulator and just go with a random length of wire? I am just running this into a DX398 for occasional shortwave listening. For your purposes you'd be better off just running a random length of wire. And since you're running a portable you probably won't want to make that wire to terribly long as you might overload the radio. dxAce Michigan USA |
#3
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Dipole Antenna Question
DJ wrote:
If I use a Budwig Dipole Center Insulator (http://www.k1cra.com/images/products/original/299.jpg) for my random length long wire antenna, should the length of the wire coming off each side of the center insulator be equal? My yard will allow me to have one side of the insulator about 200 feet long and the other side only about 50 feet. Should I even mess with the center insulator and just go with a random length of wire? I am just running this into a DX398 for occasional shortwave listening. Don't worry about the two sides being equal. That's only important if you intend to transmit and need the antenna to have a predictable impedance. For receiving, the name of the game is to put up as much wire as possible. A random length of wire will probably work just fine. -- Doug Smith W9WI Pleasant View (Nashville), TN EM66 http://www.w9wi.com |
#4
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Dipole Antenna Question
"dxAce" wrote in message ... DJ wrote: If I use a Budwig Dipole Center Insulator (http://www.k1cra.com/images/products/original/299.jpg) for my random length long wire antenna, should the length of the wire coming off each side of the center insulator be equal? My yard will allow me to have one side of the insulator about 200 feet long and the other side only about 50 feet. Should I even mess with the center insulator and just go with a random length of wire? I am just running this into a DX398 for occasional shortwave listening. For your purposes you'd be better off just running a random length of wire. And since you're running a portable you probably won't want to make that wire to terribly long as you might overload the radio. Thanks, overload is an issue. The 398 has a limited gain control. Is there a receiver that can handle 200+ feet of wire without overload problems? |
#5
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Dipole Antenna Question
On Wed, 16 Aug 2006 17:28:59 -0500, "DJ"
wrote: Thanks, overload is an issue. The 398 has a limited gain control. Is there a receiver that can handle 200+ feet of wire without overload problems? http://www.universal-radio.com/catalog/commrxvr.html Any of these. |
#6
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Dipole Antenna Question
In article ,
"DJ" wrote: If I use a Budwig Dipole Center Insulator (http://www.k1cra.com/images/products/original/299.jpg) for my random length long wire antenna, should the length of the wire coming off each side of the center insulator be equal? My yard will allow me to have one side of the insulator about 200 feet long and the other side only about 50 feet. Should I even mess with the center insulator and just go with a random length of wire? I am just running this into a DX398 for occasional shortwave listening. Thanks. For the antenna to fit the definition of a dipole the two sides need to be equal but for receiving they don't have to be equal. One side can be longer than the other and work well. A small portable radio is not designed to handle that large an antenna the size of 50 / 200 feet long so you might try 25 / 50 foot long antenna. -- Telamon Ventura, California |
#7
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Dipole Antenna Question
"dxAce" wrote in message ... For your purposes you'd be better off just running a random length of wire. And since you're running a portable you probably won't want to make that wire to terribly long as you might overload the radio. overload My longwire currently goes into a modified DX398 through an input that is 1000 ohm, high impedance. Will overload still be an issue? |
#8
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External Shortwave Antenna OverLoad - Is It A Problem ? - Do I Have It ?
DJ wrote: "dxAce" wrote in message ... For your purposes you'd be better off just running a random length of wire. And since you're running a portable you probably won't want to make that wire to terribly long as you might overload the radio. overload My longwire currently goes into a modified DX398 through an input that is 1000 ohm, high impedance. Will overload still be an issue? DJ, When you are hearing the same local AM Radio Stations -or- sometimes FM Radio or TV Stations all across your Radio Dial and on several Bands then you usually have External Shortwave Antenna OverLoad; and need to Trim (cut-back) the size of the Antenna Wire -or- Attenuate the Antenna Signal coming into the Radio. The classic sign of OverLoad is hearing local AM Radio Stations at several spots in the Shortwave Bands. Then again sometimes it ain't the External Shortwave Antenna : It is the AM/FM Shortwave Radio that needs fixing or replacing. DJ - More information is required. How is the 1000 Ohm Input configured ? READ - Portable AM/FM Shortwave Radio-to-Antenna "GIZMOE" Connector Box http://groups.google.com/group/rec.r...1903626f5e6d70 http://groups.yahoo.com/group/Shortw...a/message/2070 http://groups.yahoo.com/group/Shortw...a/message/1489 http://groups.yahoo.com/group/Shortw...na/message/957 http://groups.yahoo.com/group/Shortw...enna/message/7 NOTE - Improved Circuit and Description : + Continuous "Ground Rail" 'tie-in' for All Components + Jack-Connector to 'match' the Antenna Lead-in. + High Voltage Discharge protection using Gas Discharge Tube + Low Voltage Surge protection using Front-to-Back Dual Diodes + Static Discharge protection using 10K Ohm Potentiometer + + RF Signal Attenuation using the same 10K Ohm Potentiometer + Not-in-Use protection using an Circuit "Open" Switch + Plug-Connector to 'match' the Radio's External Antenna Input. http://groups.google.com/group/rec.r...bfe14ab2ec6900 NOTE - If you use the NE-2 Lite-Bulb and on a 'normal day' the Bulb is always Glowing or Blinking; then Trim your Antenna by 25 Feet and check it again - repeat as needed. http://groups.google.com/group/rec.r...6995600a6e2edd PROTECTING THE "PORTABLE" AM/FM SHORTWAVE RADIO FROM THE ANTENNA : If the Radio Listener has their 'portable' AM/FM Shortwave Radio permanently connected to an Out-Side External Shortwave Antenna. I recommend that they consider building and using a "GIZMO" Connector Box between the Antenna and the Radio. http://groups.google.com/group/rec.r...a9bb618defeca2 READ - "Portable Wire Antenna" (PWA) for your 'portable' AM/FM/Shortwave Radio http://groups.yahoo.com/group/Shortw...a/message/1728 "Portable Wire Antenna" (PWA) by Tom Sevart [N2UHC] hope this helps - iane ~ RHF |
#9
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External Shortwave Antenna OverLoad - Is It A Problem ? - Do I Have It ?
"RHF" wrote in message ups.com... overload My longwire currently goes into a modified DX398 through an input that is 1000 ohm, high impedance. Will overload still be an issue? DJ, DJ - More information is required. How is the 1000 Ohm Input configured ? Thanks for all the great links, and reading material. I have no idea how it is configured. Its the Radio Labs 909 modification, even though mine is technically a 398. http://www.radiolabs.com/products/re...s/super909.php DJ |
#10
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Dipole Antenna Question
On Fri, 18 Aug 2006 05:12:37 GMT, Telamon
wrote: It's not that the radio input won't be damaged by the excessive signal levels but the term "overload" means the hight levels will cause the radio to reproduce signals where they do not belong on the dial. Not operating in the linear portion of its curve... |
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