Re: [Elecraft] Grounding, Lightning & Attic Antennas
On 7/29/2023 7:18 PM, Steve L wrote: What I don’t clearly see is how to provide a station and antenna ground for a basement operating position. Steve, Email reflectors are NOT the place to learn this stuff, but they are the place to learn where to learn it. STUDY the link I provided to my tutorial, and/or the N0AX (Ward Silver) ARRL Book. k9yc.com/publish.htm Scroll down. 73, Jim K9YC __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Grounding, Lightning & Attic Antennas
I might add to my own question… - All wiring entering the house and in the development is underground: electricity, phone, internet - I can guarantee our builder did not use lead lined plywood for the roof deck otherwise creating a faraday shield in the attic - There’s no Hardee board (concrete) or aluminum siding, or stucco, or aluminum foil vapor barrier in the construction I am considering a horizontal loop antenna matched by an Icom AH-4 in the attic. What I don’t clearly see is how to provide a station and antenna ground for a basement operating position. Steve AA8AF > On Jul 29, 2023, at 11:41 AM, Steve L wrote: > > Jim & Co., > I’m reading all the recent posts on the Elecraft reflector concerning > lightning protection… > > After a recent move, I am working on the design and construction of attic > antennas for both HF and V/UHF. The topic of grounding and/or providing > lightning protection for this installation has baffled me given no outside > presence of any antenna components. While not so concerned about a direct > strike (perhaps naively?) I am concerned about induced currents and resulting > equipment damage - where clearly disconnection may be the best protection. > > Might anyone have any good references for reading/study on grounding > recommendations, how to’s, best practices, etc. for attic antennas? > > Thanks a bunch, > > 73, > Steve > AA8AF __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
[Elecraft] Elecraft CW Net Announcement
Good Evening, The sun has been active this week. Earlier today there was a radio black out due to a cloud of protons hitting the ionosphere. An earth directed CME will follow in a couple of days. Spot 3384 may flare soon. I hope to hear a few thunderstorms tomorrow. Weather has been mild this week with a few mornings of fog, one of them turned into slow rain. The local berry crop is doing well. Thimble berries ripening but not plentiful, strawberries scarce and overripe, blackberries common but not yet ripe, huckleberries fairly common and ripe, salmon berries mostly gone, Oregon grapes, tasty if you don't mind seeds, about a month away. Please join us on (or near): 14050 kHz at 2200z Sunday (3 PM PDT Sunday) 7047 kHz at z Monday (5 PM PDT Sunday) 73, Kevin. KD5ONS - Cosmogenesis simulation using ~24,000 processors for one month of computer time. Begin with a universe of hydrogen gas. Add gravity and observe for a few billion years. https://scx2.b-cdn.net/gfx/video/2018/astrophysici.mp4 https://www.tng-project.org/movies/tng/tng50_sb2_gasvel_stars_1080p.mp4 https://www.tng-project.org/media/ A little Japanese metal: https://www.youtube.com/watch?v=prSTQZZG-WA 25:00 is good __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] [OT] A dumb question about lightning
> Lightning can’t tell whether something is grounded > because the energy pulse hasn’t gotten that far yet. [Full bottom quote follows reply.] The path for lightning is determined before the main pulse of energy loss happens, and much of the communication involved in determining the path happens at the speed of light. The actual lightning flash is a wave of energy conversion, from electrostatic, to heat (and then to sound and light). The energy to drive it is already there. It is isn't travelling down the growing bolt, but rather being taken from the volume surrounding it. In fact, the main energy conversion doesn't happen until after the complete initial path has been established and actually propagates upwards. Where it happens will be influenced by the distance between grounded conductors and the cloud, so, at the early stages, the presence of grounds (although not necessarily particularly good ones) will have an impact. However, it will also depend on the degree of corona discharge, which will depend on the sharpness of objects, as corona discharges will, effectively extend the effect of the ground into the air above the point. The whole process will be complicated, and there will be a significant random element, but the presence of grounded conductors will have an effect in the very early stages. -- David Woolley On 28/07/2023 22:46, Walter Underwood wrote: Lightning can’t tell whether something is grounded because the energy pulse hasn’t gotten that far yet. Lightning induces a current in every nearby conductor. When that pulse of current reaches a building or electronics, we want to provide a low impedance path to a safe sink (ground rods) and a high impedance path to the equipment (a choke). A lightning arrestor is a temporary low impedance path to ground for conductors that aren’t normally grounded. The best high impedance path is disconnecting your equipment. That won’t stop a direct strike, because that will induce currents in the disconnected equipment. But it will help almost all the time. Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to wun...@wunderwood.org __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Grounding, Lightning & Attic Antennas
And all other cables entering the house. Much of the damage caused by lightning stems from currents induced in conductors entering the house caused by the intense electromagnetic fields. Lightning is an RF event. 73, Fred ["Skip"] K6DGW Sparks NV DM09dn Washoe County Ray Maxfield wrote on 7/29/2023 10:39 AM: If you are using Attic Antenna's .. I would focus on the Power lines. wa6vab Ray k3 On Sat, Jul 29, 2023 at 10:11 AM Rick NK7I wrote: Heh, try Hardee board (concrete) or aluminum siding, or stucco (wire based to hold it together). Or clay brick roofing. BUT that also contains wifi within the structure for network security hi hi. If the antenna choice is HOA based (yuck, ick, ew) perhaps laying the invisible wire ON the roof will work (better) for you (install on a week day while everyone is at work/school). The other issues include potent RFI in the building (smoke detectors are great receivers, particularly on 40M; GFCI devices are second best). 73, Rick nk7i On 7/29/2023 9:46 AM, Dr. William J. Schmidt wrote: A bigger concern for attic antennas is the use of "radiation shield" plywood on the roof of houses build in the last 10 years or so that turn the attic into a Faraday cage. The single most annoying reason cell phones don't work inside your houses anymore. Dr. William J. Schmidt - K9HZ J68HZ -Original Message- From: elecraft-boun...@mailman.qth.net On Behalf Of Steve L Sent: Saturday, July 29, 2023 10:42 AM To: elecraft@mailman.qth.net Subject: [Elecraft] Grounding, Lightning & Attic Antennas Jim & Co., I’m reading all the recent posts on the Elecraft reflector concerning lightning protection… After a recent move, I am working on the design and construction of attic antennas for both HF and V/UHF. The topic of grounding and/or providing lightning protection for this installation has baffled me given no outside presence of any antenna components. While not so concerned about a direct strike (perhaps naively?) I am concerned about induced currents and resulting equipment damage - where clearly disconnection may be the best protection. Might anyone have any good references for reading/study on grounding recommendations, how to’s, best practices, etc. for attic antennas? Thanks a bunch, 73, Steve AA8AF __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to b...@wjschmidt.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to rick.n...@gmail.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to wa6...@gmail.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to k6dg...@gmail.com -- This email has been checked for viruses by AVG antivirus software. www.avg.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Grounding, Lightning & Attic Antennas
If you are using Attic Antenna's .. I would focus on the Power lines. wa6vab Ray k3 On Sat, Jul 29, 2023 at 10:11 AM Rick NK7I wrote: > Heh, try Hardee board (concrete) or aluminum siding, or stucco (wire > based to hold it together). Or clay brick roofing. > > BUT that also contains wifi within the structure for network security hi > hi. > > If the antenna choice is HOA based (yuck, ick, ew) perhaps laying the > invisible wire ON the roof will work (better) for you (install on a week > day while everyone is at work/school). The other issues include potent > RFI in the building (smoke detectors are great receivers, particularly > on 40M; GFCI devices are second best). > > 73, > Rick nk7i > > On 7/29/2023 9:46 AM, Dr. William J. Schmidt wrote: > > A bigger concern for attic antennas is the use of "radiation shield" > plywood on the roof of houses build in the last 10 years or so that turn > the attic into a Faraday cage. The single most annoying reason cell phones > don't work inside your houses anymore. > > > > > > Dr. William J. Schmidt - K9HZ J68HZ > > > > > > -Original Message- > > From: elecraft-boun...@mailman.qth.net > On Behalf Of Steve L > > Sent: Saturday, July 29, 2023 10:42 AM > > To: elecraft@mailman.qth.net > > Subject: [Elecraft] Grounding, Lightning & Attic Antennas > > > > Jim & Co., > > I’m reading all the recent posts on the Elecraft reflector concerning > lightning protection… > > > > After a recent move, I am working on the design and construction of > attic antennas for both HF and V/UHF. The topic of grounding and/or > providing lightning protection for this installation has baffled me given > no outside presence of any antenna components. While not so concerned > about a direct strike (perhaps naively?) I am concerned about induced > currents and resulting equipment damage - where clearly disconnection may > be the best protection. > > > > Might anyone have any good references for reading/study on grounding > recommendations, how to’s, best practices, etc. for attic antennas? > > > > Thanks a bunch, > > > > 73, > > Steve > > AA8AF > > __ > > Elecraft mailing list > > Home: http://mailman.qth.net/mailman/listinfo/elecraft > > Help: http://mailman.qth.net/mmfaq.htm > > Post: mailto:Elecraft@mailman.qth.net > > > > This list hosted by: http://www.qsl.net > > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to b...@wjschmidt.com > > > > __ > > Elecraft mailing list > > Home: http://mailman.qth.net/mailman/listinfo/elecraft > > Help: http://mailman.qth.net/mmfaq.htm > > Post: mailto:Elecraft@mailman.qth.net > > > > This list hosted by: http://www.qsl.net > > Please help support this email list: http://www.qsl.net/donate.html > > Message delivered to rick.n...@gmail.com > __ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to wa6...@gmail.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Grounding, Lightning & Attic Antennas
Heh, try Hardee board (concrete) or aluminum siding, or stucco (wire based to hold it together). Or clay brick roofing. BUT that also contains wifi within the structure for network security hi hi. If the antenna choice is HOA based (yuck, ick, ew) perhaps laying the invisible wire ON the roof will work (better) for you (install on a week day while everyone is at work/school). The other issues include potent RFI in the building (smoke detectors are great receivers, particularly on 40M; GFCI devices are second best). 73, Rick nk7i On 7/29/2023 9:46 AM, Dr. William J. Schmidt wrote: A bigger concern for attic antennas is the use of "radiation shield" plywood on the roof of houses build in the last 10 years or so that turn the attic into a Faraday cage. The single most annoying reason cell phones don't work inside your houses anymore. Dr. William J. Schmidt - K9HZ J68HZ -Original Message- From: elecraft-boun...@mailman.qth.net On Behalf Of Steve L Sent: Saturday, July 29, 2023 10:42 AM To: elecraft@mailman.qth.net Subject: [Elecraft] Grounding, Lightning & Attic Antennas Jim & Co., I’m reading all the recent posts on the Elecraft reflector concerning lightning protection… After a recent move, I am working on the design and construction of attic antennas for both HF and V/UHF. The topic of grounding and/or providing lightning protection for this installation has baffled me given no outside presence of any antenna components. While not so concerned about a direct strike (perhaps naively?) I am concerned about induced currents and resulting equipment damage - where clearly disconnection may be the best protection. Might anyone have any good references for reading/study on grounding recommendations, how to’s, best practices, etc. for attic antennas? Thanks a bunch, 73, Steve AA8AF __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to b...@wjschmidt.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to rick.n...@gmail.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] [OT] A dumb question about lightning
I have the lightning tracker apps and monitor 3 local radar locations. Also, we keep and eye to the sky and our golden retrievers can sense lightning approaching. My wife and dogs were in the yard under partly cloudy skies and little rumbles 15 to 20 miles away. A strike happened about 500 feet from the house. Pretty much out of "the blue". It was a big one. Wife and puppies came running to the back door. Be careful. 73 Bill K3SV On 7/29/2023 12:18 PM, Gary K9GS wrote: I've found this lightning tracker app to be pretty accurate. https://play.google.com/store/apps/details?id=com.jrustonapps.mylightningtracker73,Gary K9GS Original message From: Drew AF2Z Date: 7/29/23 10:48 AM (GMT-06:00) To: elecraft@mailman.qth.net Subject: Re: [Elecraft] [OT] A dumb question about lightning I keep a close watch on the weather during lightning season here. Also, I often have the AM broadcast band on and, depending on the distance and power output of various stations, can hear the lightning strikes as they build into the region.In the shack I watch the realtime lightning map at lightningmaps.org which is also a useful tool to let you know when you might want to start shutting down. When lightning activity is getting close you can hear a strike on the radio and see it appear moments later on the map.73,DrewAF2ZOn 07/28/23 18:04, Keith Trinity WE6R wrote:> Please, PLEASE disconnect your COMPUTER from your radio(s) if lightning > is in the area!> > Almost ALWAYS lightning damaged gear that comes in for repair, was hit > _thru the comm port!_> (lightning hits Cable/DSL lines).> > As far as repairs I see, it is not common for it to be damaged from > lightning coming in the antenna.> > It usually gets to your computer, then radio gear.> > A direct hit however, and all bets are off. I've seen it come in/out via > DC, keyer, PTT IN, even the ground lug, IE anything metal.> > Keith WE6R Elecraft K3/K4 Tech> > __> Elecraft mailing list> Home: http://mailman.qth.net/mailman/listinfo/elecraft> Help: http://mailman.qth.net/mmfaq.htm> Post: mailto:Elecraft@mailman.qth.net> > This list hosted by: http://www.qsl.net> Please help support this email list: http://www.qsl.net/donate.html> Message delivered to pubx1@af2z.net__Elecraft mailing listHome: http://mailman.qth.net/mailman/listinfo/elecraftHelp: http://mailman.qth.net/mmfaq.htmPost: mailto:elecr...@mailman.qth.netThis list hosted by: http://www.qsl.netPlease help support this email list: http://www.qsl.net/donate.htmlMessage delivered to k...@gjschwartz.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to k...@pa.net __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Grounding, Lightning & Attic Antennas
A bigger concern for attic antennas is the use of "radiation shield" plywood on the roof of houses build in the last 10 years or so that turn the attic into a Faraday cage. The single most annoying reason cell phones don't work inside your houses anymore. Dr. William J. Schmidt - K9HZ J68HZ -Original Message- From: elecraft-boun...@mailman.qth.net On Behalf Of Steve L Sent: Saturday, July 29, 2023 10:42 AM To: elecraft@mailman.qth.net Subject: [Elecraft] Grounding, Lightning & Attic Antennas Jim & Co., I’m reading all the recent posts on the Elecraft reflector concerning lightning protection… After a recent move, I am working on the design and construction of attic antennas for both HF and V/UHF. The topic of grounding and/or providing lightning protection for this installation has baffled me given no outside presence of any antenna components. While not so concerned about a direct strike (perhaps naively?) I am concerned about induced currents and resulting equipment damage - where clearly disconnection may be the best protection. Might anyone have any good references for reading/study on grounding recommendations, how to’s, best practices, etc. for attic antennas? Thanks a bunch, 73, Steve AA8AF __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to b...@wjschmidt.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] [OT] A dumb question about lightning
I've found this lightning tracker app to be pretty accurate. https://play.google.com/store/apps/details?id=com.jrustonapps.mylightningtracker73,Gary K9GS Original message From: Drew AF2Z Date: 7/29/23 10:48 AM (GMT-06:00) To: elecraft@mailman.qth.net Subject: Re: [Elecraft] [OT] A dumb question about lightning I keep a close watch on the weather during lightning season here. Also, I often have the AM broadcast band on and, depending on the distance and power output of various stations, can hear the lightning strikes as they build into the region.In the shack I watch the realtime lightning map at lightningmaps.org which is also a useful tool to let you know when you might want to start shutting down. When lightning activity is getting close you can hear a strike on the radio and see it appear moments later on the map.73,DrewAF2ZOn 07/28/23 18:04, Keith Trinity WE6R wrote:> Please, PLEASE disconnect your COMPUTER from your radio(s) if lightning > is in the area!> > Almost ALWAYS lightning damaged gear that comes in for repair, was hit > _thru the comm port!_> (lightning hits Cable/DSL lines).> > As far as repairs I see, it is not common for it to be damaged from > lightning coming in the antenna.> > It usually gets to your computer, then radio gear.> > A direct hit however, and all bets are off. I've seen it come in/out via > DC, keyer, PTT IN, even the ground lug, IE anything metal.> > Keith WE6R Elecraft K3/K4 Tech> > __> Elecraft mailing list> Home: http://mailman.qth.net/mailman/listinfo/elecraft> Help: http://mailman.qth.net/mmfaq.htm> Post: mailto:Elecraft@mailman.qth.net> > This list hosted by: http://www.qsl.net> Please help support this email list: http://www.qsl.net/donate.html> Message delivered to pubx1@af2z.net__Elecraft mailing listHome: http://mailman.qth.net/mailman/listinfo/elecraftHelp: http://mailman.qth.net/mmfaq.htmPost: mailto:elecr...@mailman.qth.netThis list hosted by: http://www.qsl.netPlease help support this email list: http://www.qsl.net/donate.htmlMessage delivered to k...@gjschwartz.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] KX3 Utility
I just installed the latest version of the KX3 Utility from Elecraft. The only glitch was when Windows Defender tried to protect me from bad people, but I knew Elecraft wasn't bad people, so overrode the warning. All went well otherwise. david KC1DNY On 7/26/2023 3:24 PM, Dave wrote: Is there a problem with the KX3 Utility? I download the Windows version and get this: KX3_Utility_Setup_1_23_5_22.exe isn’t commonly downloaded It doesn’t seem to be an .exe file ?? Any help appreciated. Tnx, Dave N8AG Sent from Mail for Windows __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to dhai...@bates.edu __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] [OT] A dumb question about lightning
I keep a close watch on the weather during lightning season here. Also, I often have the AM broadcast band on and, depending on the distance and power output of various stations, can hear the lightning strikes as they build into the region. In the shack I watch the realtime lightning map at lightningmaps.org which is also a useful tool to let you know when you might want to start shutting down. When lightning activity is getting close you can hear a strike on the radio and see it appear moments later on the map. 73, Drew AF2Z On 07/28/23 18:04, Keith Trinity WE6R wrote: Please, PLEASE disconnect your COMPUTER from your radio(s) if lightning is in the area! Almost ALWAYS lightning damaged gear that comes in for repair, was hit _thru the comm port!_ (lightning hits Cable/DSL lines). As far as repairs I see, it is not common for it to be damaged from lightning coming in the antenna. It usually gets to your computer, then radio gear. A direct hit however, and all bets are off. I've seen it come in/out via DC, keyer, PTT IN, even the ground lug, IE anything metal. Keith WE6R Elecraft K3/K4 Tech __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to pu...@af2z.net __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
[Elecraft] Grounding, Lightning & Attic Antennas
Jim & Co., I’m reading all the recent posts on the Elecraft reflector concerning lightning protection… After a recent move, I am working on the design and construction of attic antennas for both HF and V/UHF. The topic of grounding and/or providing lightning protection for this installation has baffled me given no outside presence of any antenna components. While not so concerned about a direct strike (perhaps naively?) I am concerned about induced currents and resulting equipment damage - where clearly disconnection may be the best protection. Might anyone have any good references for reading/study on grounding recommendations, how to’s, best practices, etc. for attic antennas? Thanks a bunch, 73, Steve AA8AF __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] [OT] A dumb question about lightning
Just take note the link to the R56 manual is for a manual from 2005. Most of the principals have not changed but there have been changes to it over the last 18 years. (“Lessons learned” applied). 73 Dave wo2x (ex Motorolan) Sent from my iPad > On Jul 29, 2023, at 10:32 AM, Alan Bloom wrote: > > Hi Al, > > The "Bible" on this subject that has been used for many years by the > telecommunications industry is Motorola's "R56, Standards and Guidelines for > Communications Sites": > > https://www.blm.gov/sites/blm.gov/files/Lands_ROW_Motorola_R56_2005_manual.pdf > > It's kind of complicated, but it's what you have to do if you really want to > protect your site. Of special interest are Chapter 4 "External Grounding > (Earthing)", Chapter 5 "Internal Grounding (Earthing)", and Chapter 7 "Surge > Protective Devices". > > Alan N1AL > > >> On 7/28/2023 10:31 PM, Al Lorona wrote: >> Please don't laugh at me; I'm a transplant from a region of the country with >> essentially no lightning to a region where you have to worry about it quite >> a bit. >> >> We had a doozy of a storm last night, with lots of lightning overhead. I >> felt like a sitting duck, even though I had grounded both sides of the >> balanced feedline of the antenna, switched the antenna switch to the middle >> (grounded) position, and even disconnected the coax leading to the K3's >> rear-panel antenna port. >> >> Whenever lightning happens, I always wonder if it really is in fact better >> to ground everything. Because, doesn't that essentially make a lightning rod >> of the antenna? If I simply disconnected the antenna and left it floating, >> wouldn't it be less likely to attract a lightning bolt? >> >> I'm of the belief that it's better to try to avoid a direct hit than to >> attract one and trust your grounding system to do its thing. I'm of the >> belief that no grounding system is perfectly effective. >> >> Al W6LX/4 >> >> __ >> Elecraft mailing list >> Home: http://mailman.qth.net/mailman/listinfo/elecraft >> Help: http://mailman.qth.net/mmfaq.htm >> Post: mailto:Elecraft@mailman.qth.net >> >> This list hosted by: http://www.qsl.net >> Please help support this email list: http://www.qsl.net/donate.html >> Message delivered to a...@elecraft.com >> > > __ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to rocke...@gmail.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] [OT] A dumb question about lightning
Hi Al, The "Bible" on this subject that has been used for many years by the telecommunications industry is Motorola's "R56, Standards and Guidelines for Communications Sites": https://www.blm.gov/sites/blm.gov/files/Lands_ROW_Motorola_R56_2005_manual.pdf It's kind of complicated, but it's what you have to do if you really want to protect your site. Of special interest are Chapter 4 "External Grounding (Earthing)", Chapter 5 "Internal Grounding (Earthing)", and Chapter 7 "Surge Protective Devices". Alan N1AL On 7/28/2023 10:31 PM, Al Lorona wrote: Please don't laugh at me; I'm a transplant from a region of the country with essentially no lightning to a region where you have to worry about it quite a bit. We had a doozy of a storm last night, with lots of lightning overhead. I felt like a sitting duck, even though I had grounded both sides of the balanced feedline of the antenna, switched the antenna switch to the middle (grounded) position, and even disconnected the coax leading to the K3's rear-panel antenna port. Whenever lightning happens, I always wonder if it really is in fact better to ground everything. Because, doesn't that essentially make a lightning rod of the antenna? If I simply disconnected the antenna and left it floating, wouldn't it be less likely to attract a lightning bolt? I'm of the belief that it's better to try to avoid a direct hit than to attract one and trust your grounding system to do its thing. I'm of the belief that no grounding system is perfectly effective. Al W6LX/4 __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to a...@elecraft.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
[Elecraft] Lightning "protection"
Essentially, your antenna is a lightning rod. Lightning rods don't "attract" lightning. The dissipate the charge differential between the cloud and earth before the charge builds sufficiently to provide a path for a "leader" charge from earth to the cloud. When a "leader" is established, the "full charge" of a lightning strike develops. All this assumes a properly installed system. If you are actually utilizing a lightning rod system, it must be properly installed. This means solidly done interconnections between rods and a properly installed heavy wire ground. To further provide some protection, 8 foot ground rods should be installed about every 10 feet around the perimeter of the building. These rods should be bonded together. Ideally, one would use copper strapping about an inch in width. That is expensive. Another possibility is the heavy wire used by welders. The perimeter ground should be connected to the buildings electrical service ground. Then, there should be a minimum 8 foot long ground rod connected with that welding wire to each leg of the tower. At guy wire anchors, ground the guy, again with 8 foot rods. Now, bond each guy-point to one another, to the tower and to the perimeter ground at the structure housing the shack. Yes, it is a lot of work. This is the type of installation used at the 55KW TV station at which I was engineer many moons ago. 750 foot tower. The safest place in a thunderstorm was in the transmitter building. The properly installed system provided a "cone of protection" for a distance of 750 feet around the base of the tower. Much of this info was provided by an outfit called Lincole (if I recall the company name correctly) in a 2 day seminar that all the station engineers had to attend. Tom, WB2KLD __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] [OT] A dumb question about lightning
Protecting your equipment goes beyond a direct strike. I had an element in my K3 transmit final wiped out by a lightning strike a good distance away. I wasn't on the air at the time but I remember the strike. This was through a pair of Alpha-Delta switches. Sometimes I miss "the good old days" of vacuum tube rigs when I operated during thunderstorms ;-) Ken WA8JXM On Fri, Jul 28, 2023 at 7:31 PM Ray Maxfield wrote: > I worked a Number of Years as a Broadcast Engineer. > The Broadcast Industry has Put this one to bed years ago. > No Need to re-invent the Wheel. Yes, it will Cost some Dollars > to do it Right, but it can save YOUR Equipment. > Ray WA6VAB K3 > > > On Fri, Jul 28, 2023 at 3:51 PM Rick NK7I wrote: > > > We're in accord on static. Like lightning, give it someplace to go > > OUTSIDE, not via the shack/structure. Not just for noise but the > > voltages can be astoundingly high with enough amperage to cause harm. > > > > [A local puts his feeds in a glass jar then is amused at the glow of > > discharge, contained. But that is FAR from the only wire exposed. > > > > These are complex topics that few can translate well to low dollars > > (hams) and better understanding. > > > > It would have been fun to draw on that lunch crowd discussion. > > > > The only true axiom is that if you don't have enough shunting, lightning > > will be happy to show you what you missed. (Antenna didn't fall over? > > It's not big enough!). > > > > 73 Bill, > > Rick nk7i > > > > > > On 7/28/2023 3:36 PM, Dr. William J. Schmidt wrote: > > > I worked at Honeywell defense systems in the early 80's and I had two > > guys (Ph.D's from MIT) working in the office next to me that were experts > > in Meteorology... specifically the study of lightning. I would eat lunch > > with them because they were "interesting" to say the least. When they > > found out I was a ham and asking them about lightning protection they > > laughed hysterically. Over their tenure they schooled me on my lack of > > knowledge in their area and beat into me immense gravity and consequences > > of a major lightning strike. Imaginable voltages and currents. You can > > prepare but you will never be sure. > > > > > > Static is something else. All of the antennas I design and implement > > have GROUNDED elements or static chokes to ground to reduce static to a > > minimum. You learn this with experience. > > > > > > > > > Dr. William J. Schmidt - K9HZ J68HZ > > > > > > > > > -Original Message- > > > From: elecraft-boun...@mailman.qth.net < > elecraft-boun...@mailman.qth.net> > > On Behalf Of Rick NK7I > > > Sent: Friday, July 28, 2023 4:42 PM > > > To: elecraft@mailman.qth.net > > > Subject: Re: [Elecraft] [OT] A dumb question about lightning > > > > > > Not often (enough) does a ham have a 100'+ tower either. > > > > > > THE standard (of way so many to choose from) is from the cell phone > > industry (Motorola mostly). It's insanely complex but if you're on a > > mountain top and need 100% reliability; ideal. The costs, will be a > second > > mortgage so some compromises will have to happen. > > > > > > Here is a better link to the current (newest edition) of the ARRL book; > > at least a good starting point for a baseline understanding. Direct > hits, > > no matter what system/s used, will always show what you missed or didn't > do > > enough to mitigate. > > > > > > https://a.co/d/01vRC1W > > > > > > Another aspect is static reduction. That comes from wind, rain, dust, > > snow, anything that passes by the structure. Shunt all to ground OUTside > > the building is the best approach. (Base of the tower/mast and again at > > structure entry; make EVERYTHING at the same ground potential, inside and > > out. When you take a hit, that potential rises, equally if all is done > > well; it's the difference in potential that harms.) > > > > > > 73, > > > Rick nk7i > > > > > > On 7/28/2023 2:31 PM, Dr. William J. Schmidt wrote: > > >> Even the methods in that book are considered sub-standard by the > > broadcast industry... The only think that is a sure bet is to completely > > disconnect your radio and put it back in the shipping box. > > >> > > >> > > >> Dr. William J. Schmidt - K9HZ J68HZ > > >> > > >> email: b...@wjschmidt.com > > >> > > >> > > >> -Original Message- > > >> From: elecraft-boun...@mailman.qth.net > > >> > > >> Sent: Friday, July 28, 2023 4:14 PM > > >> To: j...@kk9a.com > > >> Cc: Elecraft@mailman.qth.net > > >> Subject: Re: [Elecraft] [OT] A dumb question about lightning > > >> > > >> > > >> > https://www.googleadservices.com/pagead/aclk?sa=L=DChcSEwiOk5PAqLKA > > >> AxUjEa0GHYmDBJgYABACGgJwdg=2=www.google.com > =CAASJORo_AZEA > > >> zrEwZh7d0CRaunieFV8dsSC3IDZqsPWbucgX_uNKQ=AOD64_1qxgTjvgwY4_QbQuPW > > >> 5KxSnoObmA=2ahUKEwiEsI3AqLKAAxViAjQIHe9mC-UQ0Qx6BAgOEAE > > >> > > >> Welcome to the Bible of grounding. It’ll take several reads to grasp > > what you have to do. > > >> > > >> 73, > > >>
