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#1
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![]() After reading the following paragraph, I'm wondering if my TV antenna is affecting my Antron 99 either positively or negatively... 11. If you mount two or more antennas close to each other, you will alter the transmission patterns of each one. The affect may be either positive or negative. We recommend that a minimum of 12" exist between your CB antenna and other types of antennas. http://www.firestik.com/Tech_Docs/63Things.htm Both are clamped directly to the same pipe/mast. The TV antenna is clamped 12" below the bottom of the Antron, and the highest point of the antenna is about 6" below the Antron. Another thing that's got me wondering if it is affecting the radiation pattern is that fifteen years ago, I didn't have the TV antenna under the Antron, and the neighbors whined so much about hearing me in their telephones that I put all my CB stuff in the attic. Now, I've put the exact same equipment back up two weeks ago, with the addition of the TV antenna, and I haven't had one complaint. Could the TV antenna be affecting my radiation pattern? Glenn S. Virginia Beach, VA Rat Shack DX-399 66' x 15' "L" shaped copper wire |
#2
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Glenn S. wrote in message . ..
After reading the following paragraph, I'm wondering if my TV antenna is affecting my Antron 99 either positively or negatively... 11. If you mount two or more antennas close to each other, you will alter the transmission patterns of each one. The affect may be either positive or negative. We recommend that a minimum of 12" exist between your CB antenna and other types of antennas. http://www.firestik.com/Tech_Docs/63Things.htm Both are clamped directly to the same pipe/mast. The TV antenna is clamped 12" below the bottom of the Antron, and the highest point of the antenna is about 6" below the Antron. Another thing that's got me wondering if it is affecting the radiation pattern is that fifteen years ago, I didn't have the TV antenna under the Antron, and the neighbors whined so much about hearing me in their telephones that I put all my CB stuff in the attic. Now, I've put the exact same equipment back up two weeks ago, with the addition of the TV antenna, and I haven't had one complaint. Could the TV antenna be affecting my radiation pattern? Glenn S. Virginia Beach, VA Rat Shack DX-399 66' x 15' "L" shaped copper wire To answer your question, YES, it is very possible that the tv antenna is affecting your Antron antenna. The signal could be reflecting off the tv antenna at different points which will change the radiation pattern. It is also possible that the tv antenna is affected, but if so, probably as a positive as certain tv signals can reflect off the other antenna onto the tv antenna. But if you have a ghost problem with tv reception, it could be because of the two antennas being close together. Several years ago I lived in Fair Oaks, California, and had a large Channel Master antenna mounted on a 40-ft mast with rotor. The neighbor ACROSS THE STREET noticed their reception would go in and out, and one day noticed my antenna turning as their signal went in and out. |
#3
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![]() "Glenn S." wrote in message news ![]() After reading the following paragraph, I'm wondering if my TV antenna is affecting my Antron 99 either positively or negatively... 11. If you mount two or more antennas close to each other, you will alter the transmission patterns of each one. The affect may be either positive or negative. We recommend that a minimum of 12" exist between your CB antenna and other types of antennas. http://www.firestik.com/Tech_Docs/63Things.htm Both are clamped directly to the same pipe/mast. The TV antenna is clamped 12" below the bottom of the Antron, and the highest point of the antenna is about 6" below the Antron. Because the 2 antennas are of opposite polarity- they will be essentially invisible to each other- typical isolation runs in the 20-30dB range- making interaction unnoticeable. Dale W4OP for PAR Electronics, Inc. |
#4
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Glenn S. wrote:
After reading the following paragraph, I'm wondering if my TV antenna is affecting my Antron 99 either positively or negatively... As Dale says, due to the cross-polarization (and the fact that the TV antenna is below the Antron) I doubt they're seriously affecting each other's operation. If you had a horizontally-polarized antenna 6" above the TV antenna (for example, a 10-meter Yagi) it would be a very different story. -- Doug Smith W9WI Pleasant View (Nashville), TN EM66 http://www.w9wi.com |
#5
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In article ,
Glenn S. wrote: Another thing that's got me wondering if it is affecting the radiation pattern is that fifteen years ago, I didn't have the TV antenna under the Antron, and the neighbors whined so much about hearing me in their telephones that I put all my CB stuff in the attic. Now, I've put the exact same equipment back up two weeks ago, with the addition of the TV antenna, and I haven't had one complaint. Could the TV antenna be affecting my radiation pattern? RF can get into cables and equipment, and if there are nonlinear elements like diodes or transistors or a corroded connection, they can act upon the transmitted signals to create new signals and harmonics. One time I was having huge problems with medium wave broadcast "intermod", where all over the dial there were mixtures of two or more of the local AM stations. It turned out to be a corroded connection on the FM antenna for the hi=fi tuner. So a system designed to receive 100 MHz signals was picking up 1 MHz signals, and spewing them all over 3-30 MHz range to a receiver that had no connection with the source. Figure that any long piece of metal within 100 feet of your transmitting antenna is going to pick up (and reradiate) your signal, affecting your transmission. And if it's not a very good piece of metal it can do strange things. Roof flashing, railings, masts, guy wires ... Also, if you have a TV signal booster on the antenna, it's getting hammered with quite a bit of signal. Mark Zenier Washington State resident |
#6
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In article Is83d.3044$PZ4.2757@trnddc06,
"Dale Parfitt" wrote: "Glenn S." wrote in message news ![]() After reading the following paragraph, I'm wondering if my TV antenna is affecting my Antron 99 either positively or negatively... 11. If you mount two or more antennas close to each other, you will alter the transmission patterns of each one. The affect may be either positive or negative. We recommend that a minimum of 12" exist between your CB antenna and other types of antennas. http://www.firestik.com/Tech_Docs/63Things.htm Both are clamped directly to the same pipe/mast. The TV antenna is clamped 12" below the bottom of the Antron, and the highest point of the antenna is about 6" below the Antron. Because the 2 antennas are of opposite polarity- they will be essentially invisible to each other- typical isolation runs in the 20-30dB range- making interaction unnoticeable. You mean vertical versus horizontal polarization? -- Telamon Ventura, California |
#7
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![]() "Telamon" wrote in message ... In article Is83d.3044$PZ4.2757@trnddc06, "Dale Parfitt" wrote: "Glenn S." wrote in message news ![]() After reading the following paragraph, I'm wondering if my TV antenna is affecting my Antron 99 either positively or negatively... 11. If you mount two or more antennas close to each other, you will alter the transmission patterns of each one. The affect may be either positive or negative. We recommend that a minimum of 12" exist between your CB antenna and other types of antennas. http://www.firestik.com/Tech_Docs/63Things.htm Both are clamped directly to the same pipe/mast. The TV antenna is clamped 12" below the bottom of the Antron, and the highest point of the antenna is about 6" below the Antron. Because the 2 antennas are of opposite polarity- they will be essentially invisible to each other- typical isolation runs in the 20-30dB range- making interaction unnoticeable. You mean vertical versus horizontal polarization? Or +45 and -45. The point is they must be orthogonal. Dale W4OP -- Telamon Ventura, California |
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