harnessing lightning, or not
in [Design]
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From: Joerg on 14 Jun 2010 14:24 Archimedes' Lever wrote: > On Mon, 14 Jun 2010 13:56:25 -0400, Spehro Pefhany > <speffSNIP(a)interlogDOTyou.knowwhat> wrote: > >> On Mon, 14 Jun 2010 03:04:03 -0400, "Michael A. Terrell" >> <mike.terrell(a)earthlink.net> wrote: >> >>> Joerg wrote: >>>> Michael A. Terrell wrote: >>>>> Joerg wrote: >>>>>> Michael A. Terrell wrote: >>>>>>> Joerg wrote: >>>>>>>> John Larkin wrote: >>>>>>>>> On 12 Jun 2010 07:16:54 -0700, Winfield Hill >>>>>>>>> <Winfield_member(a)newsguy.com> wrote: >>>>>>>>> >>>>>>>>>> My Maxwell capacitors hard at work energy from harnessing lightning, see my post >>>>>>>>>> with photo, at the CR4 forum. >>>>>>>>>> >>>>>>>>>> http://cr4.globalspec.com/thread/55751/Lightning-Arrestor#comment579837 >>>>>>>>> You rate 3 "good" answers out of 14. That site has very high >>>>>>>>> standards! >>>>>>>>> >>>>>>>>> Why not use the lightning to heat water? The impedance match is >>>>>>>>> potentially better, and it's easy to store hot water. We could throw a >>>>>>>>> neighborhood hot-tub party after every strike, every 40 years or so. >>>>>>>>> >>>>>>>>> We don't get lightning here. I kind of miss it. >>>>>>>>> >>>>>>>> I don't miss it, seen to much electronics come to grief from it. Hey, >>>>>>>> why don't engineers at RF module manufacturers get it into their heads >>>>>>>> that the first part after the antenna jack has got to be an inductor to >>>>>>>> ground? Anything else will eventually go *PHUT*. >>>>>>> Yawn. >>>>>>> >>>>>> T'is what I did when I just encountered the umpteenth module where that >>>>>> was done wrong :-) >>>>> >>>>> Yawn, as in: WHAT ABOUT ALL THE RF EQUIPMENT WITH A DC VOLTAGE AT THE >>>>> INPUT CONNECTOR? >>>>> >>>> Gear out in the field typically never has that. I've done a lot of RF >>>> designs and even more re-designs by now. The number of units that would >>>> be DC-fed or have to provide LNA power was zero. Fact is, units deployed >>>> in the south or on the island won't even live through the first year >>>> with a nice big inductor to ground. Lightning strike into some fence out >>>> there, voltage surge, somewhere above 100V the input cap decides it's >>>> had it ... *POP* ... preamp and final TX amp are goners. >>>> >>>> Of course, if you design sat-gear that's different. >>> >>> If they won't survive, why are there hundreds of Dish and Direct >>> satellite companies around here? Or line powered TV preamps? >> Active antennas (powered through the signal coax) are quite common on >> aircraft navigation systems too, so splitters etc. have to be >> specified with some care. > > > They are usually NOT exposed. ie under a sheath, nosecone, or dome. How's that going to help against lightning effects? -- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
From: Michael A. Terrell on 14 Jun 2010 14:40 Spehro Pefhany wrote: > > On Mon, 14 Jun 2010 03:04:03 -0400, "Michael A. Terrell" > <mike.terrell(a)earthlink.net> wrote: > > > > >Joerg wrote: > >> > >> Michael A. Terrell wrote: > >> > Joerg wrote: > >> >> Michael A. Terrell wrote: > >> >>> Joerg wrote: > >> >>>> John Larkin wrote: > >> >>>>> On 12 Jun 2010 07:16:54 -0700, Winfield Hill > >> >>>>> <Winfield_member(a)newsguy.com> wrote: > >> >>>>> > >> >>>>>> My Maxwell capacitors hard at work energy from harnessing lightning, see my post > >> >>>>>> with photo, at the CR4 forum. > >> >>>>>> > >> >>>>>> http://cr4.globalspec.com/thread/55751/Lightning-Arrestor#comment579837 > >> >>>>> You rate 3 "good" answers out of 14. That site has very high > >> >>>>> standards! > >> >>>>> > >> >>>>> Why not use the lightning to heat water? The impedance match is > >> >>>>> potentially better, and it's easy to store hot water. We could throw a > >> >>>>> neighborhood hot-tub party after every strike, every 40 years or so. > >> >>>>> > >> >>>>> We don't get lightning here. I kind of miss it. > >> >>>>> > >> >>>> I don't miss it, seen to much electronics come to grief from it. Hey, > >> >>>> why don't engineers at RF module manufacturers get it into their heads > >> >>>> that the first part after the antenna jack has got to be an inductor to > >> >>>> ground? Anything else will eventually go *PHUT*. > >> >>> > >> >>> Yawn. > >> >>> > >> >> T'is what I did when I just encountered the umpteenth module where that > >> >> was done wrong :-) > >> > > >> > > >> > Yawn, as in: WHAT ABOUT ALL THE RF EQUIPMENT WITH A DC VOLTAGE AT THE > >> > INPUT CONNECTOR? > >> > > >> > >> Gear out in the field typically never has that. I've done a lot of RF > >> designs and even more re-designs by now. The number of units that would > >> be DC-fed or have to provide LNA power was zero. Fact is, units deployed > >> in the south or on the island won't even live through the first year > >> with a nice big inductor to ground. Lightning strike into some fence out > >> there, voltage surge, somewhere above 100V the input cap decides it's > >> had it ... *POP* ... preamp and final TX amp are goners. > >> > >> Of course, if you design sat-gear that's different. > > > > > > If they won't survive, why are there hundreds of Dish and Direct > >satellite companies around here? Or line powered TV preamps? > > Active antennas (powered through the signal coax) are quite common on > aircraft navigation systems too, so splitters etc. have to be > specified with some care. The only 'aircraft' electronics I worked with was Telemetry equipment for the shuttle and ISS. Possibly AWACS, but the contract didn't really say. We did ship a lot of Telemetry equipment to DOD addresses and aircraft manufacturers. -- Anyone wanting to run for any political office in the US should have to have a DD214, and a honorable discharge.
From: Archimedes' Lever on 14 Jun 2010 14:43 On Mon, 14 Jun 2010 11:24:34 -0700, Joerg <invalid(a)invalid.invalid> wrote: >Archimedes' Lever wrote: >> On Mon, 14 Jun 2010 13:56:25 -0400, Spehro Pefhany >> <speffSNIP(a)interlogDOTyou.knowwhat> wrote: >> >>> On Mon, 14 Jun 2010 03:04:03 -0400, "Michael A. Terrell" >>> <mike.terrell(a)earthlink.net> wrote: >>> >>>> Joerg wrote: >>>>> Michael A. Terrell wrote: >>>>>> Joerg wrote: >>>>>>> Michael A. Terrell wrote: >>>>>>>> Joerg wrote: >>>>>>>>> John Larkin wrote: >>>>>>>>>> On 12 Jun 2010 07:16:54 -0700, Winfield Hill >>>>>>>>>> <Winfield_member(a)newsguy.com> wrote: >>>>>>>>>> >>>>>>>>>>> My Maxwell capacitors hard at work energy from harnessing lightning, see my post >>>>>>>>>>> with photo, at the CR4 forum. >>>>>>>>>>> >>>>>>>>>>> http://cr4.globalspec.com/thread/55751/Lightning-Arrestor#comment579837 >>>>>>>>>> You rate 3 "good" answers out of 14. That site has very high >>>>>>>>>> standards! >>>>>>>>>> >>>>>>>>>> Why not use the lightning to heat water? The impedance match is >>>>>>>>>> potentially better, and it's easy to store hot water. We could throw a >>>>>>>>>> neighborhood hot-tub party after every strike, every 40 years or so. >>>>>>>>>> >>>>>>>>>> We don't get lightning here. I kind of miss it. >>>>>>>>>> >>>>>>>>> I don't miss it, seen to much electronics come to grief from it. Hey, >>>>>>>>> why don't engineers at RF module manufacturers get it into their heads >>>>>>>>> that the first part after the antenna jack has got to be an inductor to >>>>>>>>> ground? Anything else will eventually go *PHUT*. >>>>>>>> Yawn. >>>>>>>> >>>>>>> T'is what I did when I just encountered the umpteenth module where that >>>>>>> was done wrong :-) >>>>>> >>>>>> Yawn, as in: WHAT ABOUT ALL THE RF EQUIPMENT WITH A DC VOLTAGE AT THE >>>>>> INPUT CONNECTOR? >>>>>> >>>>> Gear out in the field typically never has that. I've done a lot of RF >>>>> designs and even more re-designs by now. The number of units that would >>>>> be DC-fed or have to provide LNA power was zero. Fact is, units deployed >>>>> in the south or on the island won't even live through the first year >>>>> with a nice big inductor to ground. Lightning strike into some fence out >>>>> there, voltage surge, somewhere above 100V the input cap decides it's >>>>> had it ... *POP* ... preamp and final TX amp are goners. >>>>> >>>>> Of course, if you design sat-gear that's different. >>>> >>>> If they won't survive, why are there hundreds of Dish and Direct >>>> satellite companies around here? Or line powered TV preamps? >>> Active antennas (powered through the signal coax) are quite common on >>> aircraft navigation systems too, so splitters etc. have to be >>> specified with some care. >> >> >> They are usually NOT exposed. ie under a sheath, nosecone, or dome. > > >How's that going to help against lightning effects? An antenna under a dome or sheath will not be an attractor for lightning like a raw, exposed stick would, so the strike will be upon the craft, not the antenna. The only effect after that are the induced EM effects, if any.
From: Joerg on 14 Jun 2010 14:57 Archimedes' Lever wrote: > On Mon, 14 Jun 2010 11:24:34 -0700, Joerg <invalid(a)invalid.invalid> > wrote: > >> Archimedes' Lever wrote: >>> On Mon, 14 Jun 2010 13:56:25 -0400, Spehro Pefhany >>> <speffSNIP(a)interlogDOTyou.knowwhat> wrote: >>> >>>> On Mon, 14 Jun 2010 03:04:03 -0400, "Michael A. Terrell" >>>> <mike.terrell(a)earthlink.net> wrote: >>>> >>>>> Joerg wrote: >>>>>> Michael A. Terrell wrote: >>>>>>> Joerg wrote: >>>>>>>> Michael A. Terrell wrote: >>>>>>>>> Joerg wrote: >>>>>>>>>> John Larkin wrote: >>>>>>>>>>> On 12 Jun 2010 07:16:54 -0700, Winfield Hill >>>>>>>>>>> <Winfield_member(a)newsguy.com> wrote: >>>>>>>>>>> >>>>>>>>>>>> My Maxwell capacitors hard at work energy from harnessing lightning, see my post >>>>>>>>>>>> with photo, at the CR4 forum. >>>>>>>>>>>> >>>>>>>>>>>> http://cr4.globalspec.com/thread/55751/Lightning-Arrestor#comment579837 >>>>>>>>>>> You rate 3 "good" answers out of 14. That site has very high >>>>>>>>>>> standards! >>>>>>>>>>> >>>>>>>>>>> Why not use the lightning to heat water? The impedance match is >>>>>>>>>>> potentially better, and it's easy to store hot water. We could throw a >>>>>>>>>>> neighborhood hot-tub party after every strike, every 40 years or so. >>>>>>>>>>> >>>>>>>>>>> We don't get lightning here. I kind of miss it. >>>>>>>>>>> >>>>>>>>>> I don't miss it, seen to much electronics come to grief from it. Hey, >>>>>>>>>> why don't engineers at RF module manufacturers get it into their heads >>>>>>>>>> that the first part after the antenna jack has got to be an inductor to >>>>>>>>>> ground? Anything else will eventually go *PHUT*. >>>>>>>>> Yawn. >>>>>>>>> >>>>>>>> T'is what I did when I just encountered the umpteenth module where that >>>>>>>> was done wrong :-) >>>>>>> Yawn, as in: WHAT ABOUT ALL THE RF EQUIPMENT WITH A DC VOLTAGE AT THE >>>>>>> INPUT CONNECTOR? >>>>>>> >>>>>> Gear out in the field typically never has that. I've done a lot of RF >>>>>> designs and even more re-designs by now. The number of units that would >>>>>> be DC-fed or have to provide LNA power was zero. Fact is, units deployed >>>>>> in the south or on the island won't even live through the first year >>>>>> with a nice big inductor to ground. Lightning strike into some fence out >>>>>> there, voltage surge, somewhere above 100V the input cap decides it's >>>>>> had it ... *POP* ... preamp and final TX amp are goners. >>>>>> >>>>>> Of course, if you design sat-gear that's different. >>>>> If they won't survive, why are there hundreds of Dish and Direct >>>>> satellite companies around here? Or line powered TV preamps? >>>> Active antennas (powered through the signal coax) are quite common on >>>> aircraft navigation systems too, so splitters etc. have to be >>>> specified with some care. >>> >>> They are usually NOT exposed. ie under a sheath, nosecone, or dome. >> >> How's that going to help against lightning effects? > > > An antenna under a dome or sheath will not be an attractor for > lightning like a raw, exposed stick would, so the strike will be upon the > craft, not the antenna. The only effect after that are the induced EM > effects, if any. It is not about a direct strike, it is about coupled voltage spikes from strikes in the vicinity. If you don't have a conductive path right from antenna to GND that typically means more field failures. A lot more. -- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
From: Spehro Pefhany on 14 Jun 2010 15:07
On Mon, 14 Jun 2010 11:43:55 -0700, Archimedes' Lever <OneBigLever(a)InfiniteSeries.Org> wrote: >On Mon, 14 Jun 2010 11:24:34 -0700, Joerg <invalid(a)invalid.invalid> >wrote: > >>Archimedes' Lever wrote: >>> On Mon, 14 Jun 2010 13:56:25 -0400, Spehro Pefhany >>> <speffSNIP(a)interlogDOTyou.knowwhat> wrote: >>> >>>> On Mon, 14 Jun 2010 03:04:03 -0400, "Michael A. Terrell" >>>> <mike.terrell(a)earthlink.net> wrote: >>>> >>>>> Joerg wrote: >>>>>> Michael A. Terrell wrote: >>>>>>> Joerg wrote: >>>>>>>> Michael A. Terrell wrote: >>>>>>>>> Joerg wrote: >>>>>>>>>> John Larkin wrote: >>>>>>>>>>> On 12 Jun 2010 07:16:54 -0700, Winfield Hill >>>>>>>>>>> <Winfield_member(a)newsguy.com> wrote: >>>>>>>>>>> >>>>>>>>>>>> My Maxwell capacitors hard at work energy from harnessing lightning, see my post >>>>>>>>>>>> with photo, at the CR4 forum. >>>>>>>>>>>> >>>>>>>>>>>> http://cr4.globalspec.com/thread/55751/Lightning-Arrestor#comment579837 >>>>>>>>>>> You rate 3 "good" answers out of 14. That site has very high >>>>>>>>>>> standards! >>>>>>>>>>> >>>>>>>>>>> Why not use the lightning to heat water? The impedance match is >>>>>>>>>>> potentially better, and it's easy to store hot water. We could throw a >>>>>>>>>>> neighborhood hot-tub party after every strike, every 40 years or so. >>>>>>>>>>> >>>>>>>>>>> We don't get lightning here. I kind of miss it. >>>>>>>>>>> >>>>>>>>>> I don't miss it, seen to much electronics come to grief from it. Hey, >>>>>>>>>> why don't engineers at RF module manufacturers get it into their heads >>>>>>>>>> that the first part after the antenna jack has got to be an inductor to >>>>>>>>>> ground? Anything else will eventually go *PHUT*. >>>>>>>>> Yawn. >>>>>>>>> >>>>>>>> T'is what I did when I just encountered the umpteenth module where that >>>>>>>> was done wrong :-) >>>>>>> >>>>>>> Yawn, as in: WHAT ABOUT ALL THE RF EQUIPMENT WITH A DC VOLTAGE AT THE >>>>>>> INPUT CONNECTOR? >>>>>>> >>>>>> Gear out in the field typically never has that. I've done a lot of RF >>>>>> designs and even more re-designs by now. The number of units that would >>>>>> be DC-fed or have to provide LNA power was zero. Fact is, units deployed >>>>>> in the south or on the island won't even live through the first year >>>>>> with a nice big inductor to ground. Lightning strike into some fence out >>>>>> there, voltage surge, somewhere above 100V the input cap decides it's >>>>>> had it ... *POP* ... preamp and final TX amp are goners. >>>>>> >>>>>> Of course, if you design sat-gear that's different. >>>>> >>>>> If they won't survive, why are there hundreds of Dish and Direct >>>>> satellite companies around here? Or line powered TV preamps? >>>> Active antennas (powered through the signal coax) are quite common on >>>> aircraft navigation systems too, so splitters etc. have to be >>>> specified with some care. >>> >>> >>> They are usually NOT exposed. ie under a sheath, nosecone, or dome. >> >> >>How's that going to help against lightning effects? > > > An antenna under a dome or sheath will not be an attractor for >lightning like a raw, exposed stick would, so the strike will be upon the >craft, not the antenna. The only effect after that are the induced EM >effects, if any. Not much of a "stick" at L1, L2, or the frequencies used by the geostationary sats for WAAS, as well as sat data/voice (eg. Iridium). |