![]() |
Noise level between two ant types
Richard Harrison wrote:
Gene W4SZ wrote: "You have not offered a single reference beyond the ARRL Handbook that supports your model for noise generation." (Directed to Cecil) Particle discharge makes radio static noise. Look at Terman`s description of "precipitation static". Instead of charged particles blowing in the wind and alighting on stationary antennas, Terman describes aircraft and their antennas flying through clouds of charged particles. The effect is the same. Terman`s solution: keep the antennas away from sharp points on the aircraft which tend to noisly discharge the aircraft, insulate antenna wires, and put Faraday shields on the directional antenna loops. a PDF reference http://tinyurl.com/h4o6u I've done a bit of googling on the subject, and find that most seem to favor this sort of explanation of the phenomenon. A notable exception is W8JI. To Tom's credit he performs some experiments along those lines. I'm not completely sure that I buy the conclusions, but I'll digest them a bit more. I would suggest that Tom may want to experiment with charging dust particles with that HV source rather than water. Some have suggested that Cecil's statements are invalid because he hasn't done the experiments - not so. His view represents the mainstream. The debunkers have the burden of proof. - 73 de Mike KB3EIA - |
Noise level between two ant types
Tom Donaly wrote:
gravity wrote: "Tom Donaly" wrote in message om... Dave wrote: Jim Kelley wrote: Tom Donaly wrote: Where's the experimental evidence, Cecil? Ever heard of Ben Franklin? :-) 73, ac6xg Every winter here in New England we run numerous experiments, every time I walk across the living room and touch a metal door knob. The US military has an ESD specification of 25 KV @ 5 KOhms from a healthy capacitor as a simulator. Electro static discharge on antennas has been around for years. It is real! Dry Climate and Wind are all that's needed. Now, is the Physics at the air molecule level [Oxygen, Nitrogen, etc.], ionized Oxygen or Nitrogen atoms, charged dust particle level [that just begs the issue ... how did the dust get charged?], Van De Graff level, etc.? Who knows? But, the antenna ESD is a very REAL effect. You can hypothesize the cause all day. To solve the problem at the system level, I added an ESD bleed into my antenna switches. I'm going to filter this thread to the circular file. No one said ESD didn't exist. But you hit the nail on the head so far as wind caused ESD, "Who knows?" I don't, and neither does Cecil, although he thinks he does. 73, Tom Donaly, KA6RUH i thought it came from distant thunderstorms? and if wind blows an ELF system around, it does get noisier. i believe that's due to physical movement of the antenna system. Gravity You could be right, who knows? Certainly not the people who are afraid to experiment. Just as a point of info Tom. Do you perform experiments to prove or disprove matters to your satisfaction on everything before accepting it? That takes a very special person to be ultimately skeptical. Your posts would indicate that... or maybe that you just enjoy busting on Cecil. 8^) - 73 de Mike KB3EIA - |
Noise level between two ant types
Gene Fuller wrote:
"The term precipitation static denotes a type of interference frequently observed in an airplane passing through snow or rain. Under such circumstances, the airplane may become electrically charged to such a high potential with respect to the surrounding space that a corona discharge breaks out at some sharp point on the plane. The interference that this corona discharge produces with radio reception, termed precipitation static, is particularly serious at short-wave and lower frequencies." Corona causes RF noise for sure. But RF noise also occurs in the complete absence of corona. RF noise in the complete absence of corona is what we have been discussing. *Nobody* is arguing that corona doesn't cause RF noise. We are arguing that RF noise can be caused by something other than corona. -- 73, Cecil http://www.qsl.net/w5dxp |
Noise level between two ant types
Mike Coslo wrote:
Some have suggested that Cecil's statements are invalid because he hasn't done the experiments - not so. His view represents the mainstream. The debunkers have the burden of proof. Yep, here's a quote from the mainstream: http://www.esda.org/basics/part1.cfm "Virtually all materials, including water and dirt particles in the air, can be triboelectrically charged." Given charged dirt (dust) particles encountering a bare-wire dipole, all the rest is simple physics. -- 73, Cecil http://www.qsl.net/w5dxp |
Noise level between two ant types
Mike Coslo wrote:
Richard Harrison wrote: Gene W4SZ wrote: "You have not offered a single reference beyond the ARRL Handbook that supports your model for noise generation." (Directed to Cecil) Particle discharge makes radio static noise. Look at Terman`s description of "precipitation static". Instead of charged particles blowing in the wind and alighting on stationary antennas, Terman describes aircraft and their antennas flying through clouds of charged particles. The effect is the same. Terman`s solution: keep the antennas away from sharp points on the aircraft which tend to noisly discharge the aircraft, insulate antenna wires, and put Faraday shields on the directional antenna loops. a PDF reference http://tinyurl.com/h4o6u I've done a bit of googling on the subject, and find that most seem to favor this sort of explanation of the phenomenon. A notable exception is W8JI. To Tom's credit he performs some experiments along those lines. I'm not completely sure that I buy the conclusions, but I'll digest them a bit more. I would suggest that Tom may want to experiment with charging dust particles with that HV source rather than water. Some have suggested that Cecil's statements are invalid because he hasn't done the experiments - not so. His view represents the mainstream. The debunkers have the burden of proof. - 73 de Mike KB3EIA - Mike, Did you actually read the reference you provided? It offers complete support for Tom's position and zero support for Cecil's position. As usual around RRAA, this entire matter has morphed into all sorts of side issues. The original and only point of controversy is whether the so-called "precipitation static" is related to corona discharge or rather to some sort of particle-by-particle charge transfer of the antenna. Cecil claims that corona cannot exist in "fairweather" conditions, although there is no reason given. Therefore the particle-by-particle hypothesis is the only reasonable choice as the noise generator. The ARRL Handbook seems to go along with that idea, although not very explicitly. Other references, including Terman and the training document you provided say that corona discharge is responsible for the noise generation. W8JI agrees with that hypothesis. 73, Gene W4SZ |
Noise level between two ant types
Cecil Moore wrote:
Gene Fuller wrote: "The term precipitation static denotes a type of interference frequently observed in an airplane passing through snow or rain. Under such circumstances, the airplane may become electrically charged to such a high potential with respect to the surrounding space that a corona discharge breaks out at some sharp point on the plane. The interference that this corona discharge produces with radio reception, termed precipitation static, is particularly serious at short-wave and lower frequencies." Corona causes RF noise for sure. But RF noise also occurs in the complete absence of corona. RF noise in the complete absence of corona is what we have been discussing. *Nobody* is arguing that corona doesn't cause RF noise. We are arguing that RF noise can be caused by something other than corona. Cecil, How do you know there is no corona discharge? Is there some special test that tells one if corona discharge is present or not? 73, Gene W4SZ |
Noise level between two ant types
Cecil Moore wrote:
Yep, here's a quote from the mainstream: http://www.esda.org/basics/part1.cfm "Virtually all materials, including water and dirt particles in the air, can be triboelectrically charged." Given charged dirt (dust) particles encountering a bare-wire dipole, all the rest is simple physics. Cecil, You have now revealed the root cause of the controversy. Try using real physics instead of simple physics. 8-) 73, Gene W4SZ |
Noise level between two ant types
Mike Coslo wrote:
Tom Donaly wrote: gravity wrote: "Tom Donaly" wrote in message om... Dave wrote: Jim Kelley wrote: Tom Donaly wrote: Where's the experimental evidence, Cecil? Ever heard of Ben Franklin? :-) 73, ac6xg Every winter here in New England we run numerous experiments, every time I walk across the living room and touch a metal door knob. The US military has an ESD specification of 25 KV @ 5 KOhms from a healthy capacitor as a simulator. Electro static discharge on antennas has been around for years. It is real! Dry Climate and Wind are all that's needed. Now, is the Physics at the air molecule level [Oxygen, Nitrogen, etc.], ionized Oxygen or Nitrogen atoms, charged dust particle level [that just begs the issue ... how did the dust get charged?], Van De Graff level, etc.? Who knows? But, the antenna ESD is a very REAL effect. You can hypothesize the cause all day. To solve the problem at the system level, I added an ESD bleed into my antenna switches. I'm going to filter this thread to the circular file. No one said ESD didn't exist. But you hit the nail on the head so far as wind caused ESD, "Who knows?" I don't, and neither does Cecil, although he thinks he does. 73, Tom Donaly, KA6RUH i thought it came from distant thunderstorms? and if wind blows an ELF system around, it does get noisier. i believe that's due to physical movement of the antenna system. Gravity You could be right, who knows? Certainly not the people who are afraid to experiment. Just as a point of info Tom. Do you perform experiments to prove or disprove matters to your satisfaction on everything before accepting it? That takes a very special person to be ultimately skeptical. Your posts would indicate that... or maybe that you just enjoy busting on Cecil. 8^) - 73 de Mike KB3EIA - Actually, when it comes to some of the issues raised on this newsgroup, yes, I do. I don't see why I should believe what Cecil makes up in his head just because he makes it up in his head. "I can't believe _that_!" said Alice. "Can't you?" the Queen said in a pitying tone. "Try again: draw a long breath, and shut your eyes." Alice laughed. "There's no use trying," she said: "one can't believe impossible things." "I daresay you haven't had much practice," said the Queen. "When I was your age, I always did it for half-an-hour a day. Why, sometimes I've believed as many as six impossible things before breakfast. There goes the shawl again!" Cecil and the White Queen would get along well together. 73, Tom Donaly, KA6RUH |
Noise level between two ant types
Mike Coslo wrote:
Richard Harrison wrote: Gene W4SZ wrote: "You have not offered a single reference beyond the ARRL Handbook that supports your model for noise generation." (Directed to Cecil) Particle discharge makes radio static noise. Look at Terman`s description of "precipitation static". Instead of charged particles blowing in the wind and alighting on stationary antennas, Terman describes aircraft and their antennas flying through clouds of charged particles. The effect is the same. Terman`s solution: keep the antennas away from sharp points on the aircraft which tend to noisly discharge the aircraft, insulate antenna wires, and put Faraday shields on the directional antenna loops. a PDF reference http://tinyurl.com/h4o6u I've done a bit of googling on the subject, and find that most seem to favor this sort of explanation of the phenomenon. A notable exception is W8JI. To Tom's credit he performs some experiments along those lines. I'm not completely sure that I buy the conclusions, but I'll digest them a bit more. I would suggest that Tom may want to experiment with charging dust particles with that HV source rather than water. Some have suggested that Cecil's statements are invalid because he hasn't done the experiments - not so. His view represents the mainstream. The debunkers have the burden of proof. - 73 de Mike KB3EIA - It doesn't represent the mainstream. Go back and actually read the references. Besides, if Cecil can't demonstrate the validity of his views experimentally, even if there are some sources that agree with him, he's just parroting the old wives. 73, Tom Donaly, KA6RUH |
Noise level between two ant types
Cecil Moore wrote:
Mike Coslo wrote: Some have suggested that Cecil's statements are invalid because he hasn't done the experiments - not so. His view represents the mainstream. The debunkers have the burden of proof. Yep, here's a quote from the mainstream: http://www.esda.org/basics/part1.cfm "Virtually all materials, including water and dirt particles in the air, can be triboelectrically charged." Given charged dirt (dust) particles encountering a bare-wire dipole, all the rest is simple physics. Prove that this causes radio frequency noise, Cecil. 73, Tom Donaly, KA6RUH |
All times are GMT +1. The time now is 05:17 PM. |
Powered by vBulletin® Copyright ©2000 - 2025, Jelsoft Enterprises Ltd.
RadioBanter.com