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Ground Or Not To Ground Receiving Antenna In Storm ?
Hello:
Have been reading up on lightning a bit, and it certainly is a confusing subject. Let's say I have an Inverted-L or a Sloper in the yard (receiving only). If a lightning storm is in the vicinity, obviously the best protection possible is to just disconnect the radio from the antenna. No differences of opinion here, I would imagine. But, as a more or less theoretical question, to minimize the possibility of lightning hitting the antenna at all, or inducing large voltages in it, is it better to just leave the now "floating" antenna alone, or is it better to ground one end of it ? Why ? Thanks, B. |
Ground Or Not To Ground Receiving Antenna In Storm ?
On Fri, 16 Dec 2005 11:20:53 -0500, "Robert11"
wrote: But, as a more or less theoretical question, to minimize the possibility of lightning hitting the antenna at all, or inducing large voltages in it, is it better to just leave the now "floating" antenna alone, or is it better to ground one end of it ? ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ I doubt it matters. A lightning bolt, having traveled thousands of feet to the vicinity of your antenna, will not be deterred by a few more inches. 73, Bill W6WRT |
Ground Or Not To Ground Receiving Antenna In Storm ?
In article , Bill Turner
wrote: On Fri, 16 Dec 2005 11:20:53 -0500, "Robert11" wrote: But, as a more or less theoretical question, to minimize the possibility of lightning hitting the antenna at all, or inducing large voltages in it, is it better to just leave the now "floating" antenna alone, or is it better to ground one end of it ? ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ I doubt it matters. A lightning bolt, having traveled thousands of feet to the vicinity of your antenna, will not be deterred by a few more inches. Bill- That's what I was going to say! I recall a field day activity where the club was using the press box of a high school football field, with antennas strung between light poles. As a storm approached, there were sparks several inches long jumping between disconnected antenna connectors and nearby grounded equipment. These sparks were induced by lightning strikes that were some distance away. Grounding would have eliminated the sparks by providing a metalic path for the discharge. I doubt it would have had any influence on whether an antenna would be directly hit, or would have provided any substantial protection in the event of a direct strike. Traditional wisdom is that having tall trees nearby, as well as tall objects such as light poles, will shield you from lightning. But there are no guarantees. And lightning doesn't always strike the top of tower! 73, Fred, K4DII |
Ground Or Not To Ground Receiving Antenna In Storm ?
On Fri, 16 Dec 2005 11:20:53 -0500, "Robert11"
wrote: Hello: Have been reading up on lightning a bit, and it certainly is a confusing subject. Let's say I have an Inverted-L or a Sloper in the yard (receiving only). If a lightning storm is in the vicinity, obviously the best protection possible is to just disconnect the radio from the antenna. No differences of opinion here, I would imagine. But, as a more or less theoretical question, to minimize the possibility of lightning hitting the antenna at all, or inducing large voltages in it, is it better to just leave the now "floating" antenna alone, or is it better to ground one end of it ? Why ? You have to think carefully about what you are trying to protect. It seems to me that in the event of a lightning stroke in the near vicinity of your antenna, large voltages will be induced in the antenna wrt "ground", whether or not your antenna or its support structure features as a streamer, or takes the current from a leader. That voltage may be sufficient for insulation breakdown, and charge will flow to ground via some path, not necessarily of your choosing. Substantial physical damage may occur where insulation breaks down, the path of the side-flash current may result in further damage to persons or equipment. If you make a substantial connection from the feedline to some thing, you have some degree of control over the path that the discharge current flows. Properly chosen and implemented, that might be better than doing nothing, but if poorly designed or implemented, it could be worse than doing nothing. Side-flash can still occur where you have provided a path to ground. Very often, the target of effective lighting protection of radio installations is minimisation of voltage drops or potential differences internal to an installation as a result of lightning discharge current rather than trying to minimise the voltage to "ground" resulting from the current. Owen -- |
Ground Or Not To Ground Receiving Antenna In Storm ?
I always tell new Hams to ground everything they can.... but if they get a
direct hit then they will be too busy fighting fire to worry about the antenna... -Dave- K5DRC Since 1969 BULL SHOALES LAKE http://www.bullshoals.org/lake.htm AR/MO STATE LINE Some day someone will give a WAR and nobody will go "Owen Duffy" wrote in message ... On Fri, 16 Dec 2005 11:20:53 -0500, "Robert11" wrote: Hello: Have been reading up on lightning a bit, and it certainly is a confusing subject. Let's say I have an Inverted-L or a Sloper in the yard (receiving only). If a lightning storm is in the vicinity, obviously the best protection possible is to just disconnect the radio from the antenna. No differences of opinion here, I would imagine. But, as a more or less theoretical question, to minimize the possibility of lightning hitting the antenna at all, or inducing large voltages in it, is it better to just leave the now "floating" antenna alone, or is it better to ground one end of it ? Why ? You have to think carefully about what you are trying to protect. It seems to me that in the event of a lightning stroke in the near vicinity of your antenna, large voltages will be induced in the antenna wrt "ground", whether or not your antenna or its support structure features as a streamer, or takes the current from a leader. That voltage may be sufficient for insulation breakdown, and charge will flow to ground via some path, not necessarily of your choosing. Substantial physical damage may occur where insulation breaks down, the path of the side-flash current may result in further damage to persons or equipment. If you make a substantial connection from the feedline to some thing, you have some degree of control over the path that the discharge current flows. Properly chosen and implemented, that might be better than doing nothing, but if poorly designed or implemented, it could be worse than doing nothing. Side-flash can still occur where you have provided a path to ground. Very often, the target of effective lighting protection of radio installations is minimisation of voltage drops or potential differences internal to an installation as a result of lightning discharge current rather than trying to minimise the voltage to "ground" resulting from the current. Owen -- |
Ground Or Not To Ground Receiving Antenna In Storm ?
On Sat, 17 Dec 2005 01:48:24 -0600, " hillbilly3302"
wrote: I always tell new Hams to ground everything they can.... but if they get a direct hit then they will be too busy fighting fire to worry about the antenna... ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ This summer my 80 foot tower took a direct hit, the first in my 48 years of hamming. The tower was grounded and there was no fire, but it tripped a circuit breaker in my house and damaged a radio connected to it. My point is that fire is not an automatic consequence. Incidentally, the sound of thunder from a hit that close is remarkably different from a hit some distance away. First, you hear the clap from the nearest part of the bolt and then from parts successively farther away, a long, rolling sound that continues much longer than one at a distance. If I don't ever hear it again, that will be ok by me. :-) 73, Bill W6WRT |
Ground Or Not To Ground Receiving Antenna In Storm ?
Bill Turner wrote:
On Sat, 17 Dec 2005 01:48:24 -0600, " hillbilly3302" wrote: I always tell new Hams to ground everything they can.... but if they get a direct hit then they will be too busy fighting fire to worry about the antenna... ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ This summer my 80 foot tower took a direct hit, the first in my 48 years of hamming. The tower was grounded and there was no fire, but it tripped a circuit breaker in my house and damaged a radio connected to it. My point is that fire is not an automatic consequence. Incidentally, the sound of thunder from a hit that close is remarkably different from a hit some distance away. First, you hear the clap from the nearest part of the bolt and then from parts successively farther away, a long, rolling sound that continues much longer than one at a distance. If I don't ever hear it again, that will be ok by me. :-) 73, Bill W6WRT Bill; Ain't been there, Ain't done that, Don't want no stinkin t-shirt. ;^) Seriously though glad that nothing really serious happened. When I was in retain sales I sold many electronic items to people that suffered both direct and indirect hits. Lots of damage no injuries everyone was lucky. Dave WD9BDZ |
Ground Or Not To Ground Receiving Antenna In Storm ?
"Bill Turner" wrote in message ... On Sat, 17 Dec 2005 01:48:24 -0600, " hillbilly3302" wrote: This summer my 80 foot tower took a direct hit, the first in my 48 years of hamming. The tower was grounded and there was no fire, but it tripped a circuit breaker in my house and damaged a radio connected to it. My point is that fire is not an automatic consequence. Incidentally, the sound of thunder from a hit that close is remarkably different from a hit some distance away. First, you hear the clap from the nearest part of the bolt and then from parts successively farther away, a long, rolling sound that continues much longer than one at a distance. If I don't ever hear it again, that will be ok by me. :-) 73, Bill W6WRT Long years ago, 50 yearsor so before I reached Ham status, a thunderstorm awakened me in the wee hours and proceeded to dance around in the shallow hill pasture near the house. Stroke after stroke occurred and all so near I could hear a loud click as the strike occurred and then the diminishing rumble. I still haven't figured out the initial click sound, it came from outside so wasn't a house internal electric phenomenon. Harold KD5SAK |
Ground Or Not To Ground Receiving Antenna In Storm ?
Bill Turner wrote:
If I don't ever hear it again, that will be ok by me. :-) Consider that there might be two ways that you would never hear it again and one is NOT OK. :-) -- 73, Cecil http://www.qsl.net/w5dxp |
Ground Or Not To Ground Receiving Antenna In Storm ?
On Fri, 16 Dec 2005 22:55:09 GMT, Owen Duffy wrote:
Very often, the target of effective lighting protection of radio installations is minimisation of voltage drops or potential differences internal to an installation as a result of lightning discharge current rather than trying to minimise the voltage to "ground" resulting from the current. I should have expanded that to say: Minimisation of potential differences is often obtained by one or more of: - providing an alternate low impedance path to ground so that less current flows through the equipment room; - single point earthing to reduce the voltage drop in earthing conductors internal to the equipment room; - equipotential bonding to reduce the voltage drop between the equipment room earth and other parts of the building, and other services or structures (eg water, gas, telephone, power). There may be standards or codes that apply to lighting protection in your area, they are worth checking, and while they may not mandate lighting protection, they may mandate the way in which it is done if it is done. That may have implications for your insurance. Effective lightning protection is a very expensive business, and if you don't need "continuous operation" and have a simple configuration, it is much cheaper and effective to ensure that feedlines and similar conductors (like rotator cables) are totally disconnected from the shack at times of high risk. Owen -- |
Ground Or Not To Ground Receiving Antenna In Storm ?
kd5sak wrote:
Long years ago, 50 yearsor so before I reached Ham status, a thunderstorm awakened me in the wee hours and proceeded to dance around in the shallow hill pasture near the house. Stroke after stroke occurred and all so near I could hear a loud click as the strike occurred and then the diminishing rumble. I still haven't figured out the initial click sound, it came from outside so wasn't a house internal electric phenomenon. I've read that this click is due to the ear's reaction to the strong electromagnetic pulse. If that's what you heard, it comes from the ear itself, not from outside. Roy Lewallen, W7EL |
Ground Or Not To Ground Receiving Antenna In Storm ?
"Roy Lewallen" wrote in message ... kd5sak wrote: Long years ago, 50 yearsor so before I reached Ham status, a thunderstorm awakened me in the wee hours and proceeded to dance around in the shallow hill pasture near the house. Stroke after stroke occurred and all so near I could hear a loud click as the strike occurred and then the diminishing rumble. I still haven't figured out the initial click sound, it came from outside so wasn't a house internal electric phenomenon. I've read that this click is due to the ear's reaction to the strong electromagnetic pulse. If that's what you heard, it comes from the ear itself, not from outside. Roy Lewallen, W7EL This is the first time I have seen it mentioned the ear reacting to the electromagnetic pulse. Most of the time it is described as the same way the old WW2 depth charges sounded in the submarines. YOu get the click and then the boom. I forgot the term used but it is something like an impulse or pressure shock wave traveling faster than the speed of sound and then the actual sound wave. |
Ground Or Not To Ground Receiving Antenna In Storm ?
I've read that this click is due to the ear's reaction to the strong
electromagnetic pulse. If that's what you heard, it comes from the ear itself, not from outside................................ According to old Gary Coffman posts, he says it's picked up by the auditory nerve. Also, deaf people can hear that click. I've had two strikes to my mast with me sitting 15 ft away from the base of the mast. I could hear that click, but I also could hear the arc sound of the strike going to ground outside. Sounded like a light bulb being thrown to the ground outside my window. Not that loud really. I'm fairly convinced the quality of the ground connection effects the loudness of the strike. The strikes that hit my well grounded mast are fairly quiet, not counting the overhead sonic boom. The strikes to the trees in the yard are super loud in comparison. A loud crack, instead of the quieter arc sound. MK |
Ground Or Not To Ground Receiving Antenna In Storm ?
But, as a more or less theoretical question, to minimize the
possibility of lightning hitting the antenna at all, or inducing large voltages in it, is it better to just leave the now "floating" antenna alone, or is it better to ground one end of it ? Why ?...................................... I prefer to ground all the feedlines. I have a ground strip outside my window with a bunch of SO-239's. I just screw em all in when bad wx is around. I doubt it will make much difference as to the likelyhood of being struck. Horizontal wire antennas are not struck that often compared to verticals, trees, etc. But if it is, I'd prefer it to be grounded to reduce flashing, etc. My metal mast takes the brunt of the strikes to ground. All my grounding of the feedline does is take any left over energy on the coax to ground. Same for induced energy from near strikes. And it can be a good bit, as I actually can hear my connectors arc with nearby strikes. Never leave antenna wires, or feedline ends in the house, or in bottles, etc..You want it out of the house if it's not protected. Even if using a grounded switch, etc, I'd prefer not to have it running through the house. IE: ground wire leading along the wall, etc to the switch to ground it. Most switches ground the unused connectors, or have a ground position. I don't like those in the house if the feed is unprotected by gas tubes, etc... MK |
Ground Or Not To Ground Receiving Antenna In Storm ?
wrote in message oups.com... I've read that this click is due to the ear's reaction to the strong electromagnetic pulse. If that's what you heard, it comes from the ear itself, not from outside................................ According to old Gary Coffman posts, he says it's picked up by the auditory nerve. Also, deaf people can hear that click. Thanks OM, I've wondered for nearly 50 years what the "click" mechanism was. I've told the story several times, but never to anyone I thought it would be useful to ask for an explanation of the "click". Harold KD5SAK |
Ground Or Not To Ground Receiving Antenna In Storm ?
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Ground Or Not To Ground Receiving Antenna In Storm ?
Ralph Mowery wrote:
This is the first time I have seen it mentioned the ear reacting to the electromagnetic pulse. Most of the time it is described as the same way the old WW2 depth charges sounded in the submarines. YOu get the click and then the boom. I forgot the term used but it is something like an impulse or pressure shock wave traveling faster than the speed of sound and then the actual sound wave. I do believe that any mechanical wave, such as a pressure or shock wave, travels at the speed of sound, no more and no less. To travel faster, it would have to be an electromagnetic wave. Roy Lewallen, W7EL |
Ground Or Not To Ground Receiving Antenna In Storm ?
I do believe that any mechanical wave, such as a pressure or shock
wave, travels at the speed of sound, no more and no less. To travel faster, it would have to be an electromagnetic wave. Also, the deaf person wouldn't hear the mechanical wave. Well, unless they had "some" hearing still available. If it was proven that a totally deaf person could hear it, that would pretty much nail it down as electromagnetic. If that came out to be true, then Coffmans theory about the auditory nerve picking it up would probably be true unless some other nerve was actually involved. MK |
Ground Or Not To Ground Receiving Antenna In Storm ?
kd5sak wrote:
"Bill Turner" wrote in message ... On Sat, 17 Dec 2005 01:48:24 -0600, " hillbilly3302" wrote: This summer my 80 foot tower took a direct hit... 73, Bill W6WRT Long years ago, 50 yearsor so before I reached Ham status, a thunderstorm awakened me in the wee hours and proceeded to dance around in the shallow hill pasture near the house. Stroke after stroke occurred and all so near I could hear a loud click as the strike occurred and then the diminishing rumble. I still haven't figured out the initial click sound, it came from outside so wasn't a house internal electric phenomenon. Harold KD5SAK A few years ago I was out fishing at my favorite pond. It had clouded over, but had not yet begun to rain. All of a sudden I could feel myself beginning to tingle, it seems to me it was more in the feet, there was a sour taste in my mouth, and then all of a sudden a bolt from the blue hit the pond not far from where I was standing -- scared the living heck out of me. The buildup of the tingling was a matter of a few seconds, then the bolt, so I still don't have full recollection of just where the bolt hit. I jumped back and landed on my butt, but other than that there was no damage. I quickly gathered my gear (not trusting the statistic that it wouldn't hit twice in the same place) and headed for the car. I sat in the car and watched the pond to see if any fish came to the surface to see what happened but no such luck! This was in the foothills of the rockies and I got quite a light show till the storm passed over! Irv VE6BP (still got a few lives to go!) -- -------------------------------------- Diagnosed Type II Diabetes March 5 2001 Beating it with diet and exercise! 297/215/210 (to be revised lower) 58"/43"(!)/44" (already lower too!) -------------------------------------- Visit my HomePage at http://members.shaw.ca/finkirv/index.html Visit my Baby Sofia website at http://members.shaw.ca/finkirv4/index.htm Visit my OLDTIMERS website at http://members.shaw.ca/finkirv5/index.htm -------------------- Irv Finkleman, Grampa/Ex-Navy/Old Fart/Ham Radio VE6BP Calgary, Alberta, Canada |
Ground Or Not To Ground Receiving Antenna In Storm ?
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Ground Or Not To Ground Receiving Antenna In Storm ?
Russ wrote:
Doesn't the delta P of a fuel-air bomb travel at greater than the speed of sound? No. Roy Lewallen, W7EL |
Ground Or Not To Ground Receiving Antenna In Storm ?
The denotation is supersonic, while the flame spread is subsonic.
"Roy Lewallen" wrote in message ... Russ wrote: Doesn't the delta P of a fuel-air bomb travel at greater than the speed of sound? No. Roy Lewallen, W7EL |
Ground Or Not To Ground Receiving Antenna In Storm ?
On Sun, 18 Dec 2005 12:39:09 -0800, Roy Lewallen
wrote: Russ wrote: Doesn't the delta P of a fuel-air bomb travel at greater than the speed of sound? No. Roy Lewallen, W7EL The definition of dentonation includes the flame front moving at supersonic speeds. http://www.globalsecurity.org/milita...itions/fae.htm R |
Ground Or Not To Ground Receiving Antenna In Storm ?
Russ wrote:
On Sun, 18 Dec 2005 12:39:09 -0800, Roy Lewallen wrote: Russ wrote: Doesn't the delta P of a fuel-air bomb travel at greater than the speed of sound? No. Roy Lewallen, W7EL The definition of dentonation includes the flame front moving at supersonic speeds. http://www.globalsecurity.org/milita...itions/fae.htm Yes, I can understand the flame front moving faster than sound, if it's not a pressure wave. I don't know the mechanism, but presume it's propagated by radiant heat. That is, a flame occurs, and its heat radiates and superheats nearby material, causing it to flame. That would be propagation by electromagnetic wave, i.e., infrared "light". The radiation would travel at the speed of light, with the apparent speed of the front being dictated by how fast the material is heated and ignited by the radiated heat. Propagation by this mechanism and at this speed would end as soon as the flame front reached the outside of the vapor cloud, beyond which the resulting pressure wave would travel at the speed of sound. I'm not an expert at this, but I'm quite sure that the only way you can get a mechanical wave to travel faster than sound is if the behavior of the air becomes nonlinear at some compression level. That could conceivably happen as a result of an explosion, but I don't think so. If anyone has any references describing such nonlinear behavior, I'd love to learn more about it. Roy Lewallen, W7EL |
Ground Or Not To Ground Receiving Antenna In Storm ?
"Robert11" wrote
is it better to just leave the now "floating" antenna alone, or is it better to ground one end of it ? ______________ Most MW broadcast stations use series-fed, insulated towers that usually are (by far) the highest structures in the area. These stations operate successfully in lightning storms using a combination of means. First is an arc gap connected across the tower feedpoint to a very low resistance earth ground (120 1/4-wave, buried radials). The gap is set to flash over at some margin above the peak voltage present during normal operation. They also use a "static drain choke" to earth ground, which is a high Z at the MW frequency, but doesn't let high static potentials develop on the tower. The last part of the protection system is supplied by transmitter circuitry that senses instantaneous phase changes in transmission line current, and kills r-f output for some milliseconds so as not to sustain any arc that occurs in the antenna system. Maybe some of these techniques could be useful in amateur radio installations. RF |
Ground Or Not To Ground Receiving Antenna In Storm ?
Roy Lewallen wrote:
I'm not an expert at this, but I'm quite sure that the only way you can get a mechanical wave to travel faster than sound is if the behavior of the air becomes nonlinear at some compression level. Carrier velocity is linear and must be taken into account. Relative to a measurement point at the center of the earth, sound waves traveling East in the surface atmosphere are moving faster than Mach 2. Do the carriers move during an explosion? -- 73, Cecil http://www.qsl.net/w5dxp |
Ground Or Not To Ground Receiving Antenna In Storm ?
"Robert11" wrote is it better to just leave the now "floating" antenna alone, or is it better to ground one end of it ? ______________ In anticipation of a thunder storm just leave it floating. Not that it will prevent a direct lightning strike but it MIGHT prevent damage to equipment and, more important, to yourself. But it is advisable not to attempt to disconnect it using bare fingers during the progress of a thunder storm. I am a little superstitious so I use the XYL's rubber kitchen gloves. There's only one thing you can be absolutely certain of - lightning exactly obeys the Mathematical Laws of Probability. See the works of Sir Ronald Arthur Fisher, the greatest statistician of all time. Beautifully explained in plain English. He dabbled mainly in Genetics, Agriculture, the Weather, and the mathematics thereof. But I'm not aware of anything specifically he had to say about the statistics of lightning strikes. You will have to work things out for yourself. In all probability nothing seriously will happen to YOU. So don't worry about it. Just DON'T fly kites using 1/2-wavelength metal wires during thunder storms. Not even on the 10m band. Or shelter from the rain under solitary trees. It's asking for trouble but you probably won't get any. As for me, I'm 80 years of age, and I'm still alive. I've never won the national lottery. But perhaps that can be explained by the fact that I've never entered it. I hope the foregoing has helped to set your mind at rest. ---- Reg, G4FGQ ========================================== |
Ground Or Not To Ground Receiving Antenna In Storm ?
Reg Edwards wrote:
. . . See the works of Sir Ronald Arthur Fisher, the greatest statistician of all time. Beautifully explained in plain English. He dabbled mainly in Genetics, Agriculture, the Weather, and the mathematics thereof. But I'm not aware of anything specifically he had to say about the statistics of lightning strikes. You will have to work things out for yourself. In all probability nothing seriously will happen to YOU. So don't worry about it. . . . As for me, I'm 80 years of age, and I'm still alive. I've never won the national lottery. But perhaps that can be explained by the fact that I've never entered it. I hope the foregoing has helped to set your mind at rest. I'd be willing to wager that there are places in Florida which have more lightning strikes in a single summer than have occurred at your QTH (or mine) in the past 80 years. Roy Lewallen, W7EL |
Ground Or Not To Ground Receiving Antenna In Storm ?
"Reg Edwards" wrote
In anticipation of a thunder storm just leave it floating. Not that it will prevent a direct lightning strike but it MIGHT prevent damage to equipment and, more important, to yourself. .... etc etc removed by major clippage I hope the foregoing has helped to set your mind at rest. __________ Possibly you thought this relevant to the original post. But then why not thread it so, rather than to mine? RF |
Ground Or Not To Ground Receiving Antenna In Storm ?
"Roy Lewallen" wrote I'd be willing to wager that there are places in Florida which have more lightning strikes in a single summer than have occurred at your QTH (or mine) in the past 80 years. ======================================= Roy, your's is a safe bet. Nevertheless, statistically speaking, the good people of Florida should be more scared of dying from gunshot wounds. But it doesn't seem to worry them very much. ---- Reg. |
Ground Or Not To Ground Receiving Antenna In Storm ?
This has been an interesting discussion, and prompted me to do a tiny
bit more research. It seems to me that if there's any nonlinear phenomenon which allows some pressure waves to travel through air faster than the speed of sound, surely a nuclear blast would produce enough pressure to excite it. But it doesn't seem to. From http://www.globalsecurity.org/wmd/intro/nuke-blast.htm: "During the time the blast wave is passing through the superheated atmosphere in the fireball, it travels at supersonic velocities. After it leaves the vicinity of the fireball, it slows down to the normal speed of sound in the atmosphere. As long as the blast wave is expanding radially, its intensity decreases approximately as the square of the distance. When the expanding blast wave from a nuclear air burst strikes the surface of the earth, however, it is reflected, and the reflected wave reinforces and intensifies the primary wave." Roy Lewallen, W7EL |
Ground Or Not To Ground Receiving Antenna In Storm ?
Reg Edwards wrote:
Nevertheless, statistically speaking, the good people of Florida should be more scared of dying from gunshot wounds. But it doesn't seem to worry them very much. Now that so many Floridians are packing, it's the criminals who should be worried. -- 73, Cecil http://www.qsl.net/w5dxp |
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