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Re: [time-nuts] GPS antenna selection - lightning

GL
Glenn Little WB4UIV
Sat, Aug 6, 2016 1:46 PM

Cone of protection is addressed.
Volume 1 is theory, volume 2 is application.
The military requires 1/0 cable exterior to the building, commercial
practice is #2AWG.
Ground rod spacing is address.

Overall a very good reference based on practical experience and backed
with theory.

73
Glenn
WB4UIV

On 8/6/2016 1:19 AM, Bill Hawkins wrote:

Hi Glenn,

Your advice is excellent.

Seems like every time we have a lightning discussion there is no
distinction between an EMP and a direct hit.

I started work in 1960 at a blasting cap plant in upstate New York. The
powder magazines were protected by tall masts according to the "cone of
protection" theory. The angle of the cone varied between 45 and 60
degrees. The earth ground resistance of the mast was measured by a
hand-cranked device that looked like a megger but read earth resistance
to less than a tenth of an ohm. Had the lightning but never lost a
magazine.

You say MIL-HDBK-419 covers EMP. Does it also cover cone of protection
for direct hits?

I was fascinated by the idea that a simple capacitor discharge into an
inductor could be greatly enhanced by reducing the diameter of the
inductor with a conventional explosive, described in one of Stephen
Coonts' books, if my failing memory recalls correctly. And so I learned
what I could about EMP. Never built anything, just interesting behavior.

Best regards,
Bill Hawkins

-----Original Message-----
From: time-nuts [mailto:time-nuts-bounces@febo.com] On Behalf Of Glenn
Little WB4UIV
Sent: Friday, August 05, 2016 9:47 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts]GPS antenna selection - lightning

A very good reference for EMP protection is MIL-HDBK-419.
This is downloadable for a number of web sources.
It is about 600 pages and is in two volumes.
This discusses a number of different sources of EMP such as nuclear and
lightning.
A lot is for protection of military industrial complexes, but, there is
a lot that pertains to us.

I worked for a military complex that assembled nuclear missiles.
The site was built to this handbook specs.
We had no EMP related damage at the site.

Number one rule, bond all grounds together. If something on your
property takes a hit, you want everything on your property to elevate to
the same level and the same rate.
If you have multiple, non bonded grounds, there is a different reference
for each ground. This is a major source for disaster.

I spent seven years in lightning mitigation. I was told by professionals
that I was wrong. The third time that their tower was struck, destroying
all of the lights and attached equipment, they followed my
recommendations. That was ten years ago. The three hits were within four
months of each other. The site has been free of destructive hits since
then.

73
Glenn
WB4UIV

--

Glenn Little                ARRL Technical Specialist  QCWA  LM 28417
Amateur Callsign:  WB4UIV            wb4uiv@arrl.net    AMSAT LM 2178
QTH:  Goose Creek, SC USA (EM92xx)  USSVI LM  NRA LM  SBE ARRL TAPR
"It is not the class of license that the Amateur holds but the class
of the Amateur that holds the license"

Cone of protection is addressed. Volume 1 is theory, volume 2 is application. The military requires 1/0 cable exterior to the building, commercial practice is #2AWG. Ground rod spacing is address. Overall a very good reference based on practical experience and backed with theory. 73 Glenn WB4UIV On 8/6/2016 1:19 AM, Bill Hawkins wrote: > Hi Glenn, > > Your advice is excellent. > > Seems like every time we have a lightning discussion there is no > distinction between an EMP and a direct hit. > > I started work in 1960 at a blasting cap plant in upstate New York. The > powder magazines were protected by tall masts according to the "cone of > protection" theory. The angle of the cone varied between 45 and 60 > degrees. The earth ground resistance of the mast was measured by a > hand-cranked device that looked like a megger but read earth resistance > to less than a tenth of an ohm. Had the lightning but never lost a > magazine. > > You say MIL-HDBK-419 covers EMP. Does it also cover cone of protection > for direct hits? > > I was fascinated by the idea that a simple capacitor discharge into an > inductor could be greatly enhanced by reducing the diameter of the > inductor with a conventional explosive, described in one of Stephen > Coonts' books, if my failing memory recalls correctly. And so I learned > what I could about EMP. Never built anything, just interesting behavior. > > Best regards, > Bill Hawkins > > > -----Original Message----- > From: time-nuts [mailto:time-nuts-bounces@febo.com] On Behalf Of Glenn > Little WB4UIV > Sent: Friday, August 05, 2016 9:47 PM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts]GPS antenna selection - lightning > > A very good reference for EMP protection is MIL-HDBK-419. > This is downloadable for a number of web sources. > It is about 600 pages and is in two volumes. > This discusses a number of different sources of EMP such as nuclear and > lightning. > A lot is for protection of military industrial complexes, but, there is > a lot that pertains to us. > > I worked for a military complex that assembled nuclear missiles. > The site was built to this handbook specs. > We had no EMP related damage at the site. > > Number one rule, bond all grounds together. If something on your > property takes a hit, you want everything on your property to elevate to > the same level and the same rate. > If you have multiple, non bonded grounds, there is a different reference > for each ground. This is a major source for disaster. > > I spent seven years in lightning mitigation. I was told by professionals > that I was wrong. The third time that their tower was struck, destroying > all of the lights and attached equipment, they followed my > recommendations. That was ten years ago. The three hits were within four > months of each other. The site has been free of destructive hits since > then. > > 73 > Glenn > WB4UIV > > > > -- ----------------------------------------------------------------------- Glenn Little ARRL Technical Specialist QCWA LM 28417 Amateur Callsign: WB4UIV wb4uiv@arrl.net AMSAT LM 2178 QTH: Goose Creek, SC USA (EM92xx) USSVI LM NRA LM SBE ARRL TAPR "It is not the class of license that the Amateur holds but the class of the Amateur that holds the license" ---------------------------------------------------------------------------
CA
Clay Autery
Sat, Aug 6, 2016 3:00 PM

Is the 1987 version the latest issue available for free?


Clay Autery, KY5G
MONTAC Enterprises
(318) 518-1389

On 8/6/2016 8:46 AM, Glenn Little WB4UIV wrote:

Cone of protection is addressed.
Volume 1 is theory, volume 2 is application.
The military requires 1/0 cable exterior to the building, commercial
practice is #2AWG.
Ground rod spacing is address.

Overall a very good reference based on practical experience and backed
with theory.

73
Glenn
WB4UIV

On 8/6/2016 1:19 AM, Bill Hawkins wrote:

Hi Glenn,

Your advice is excellent.

Seems like every time we have a lightning discussion there is no
distinction between an EMP and a direct hit.

I started work in 1960 at a blasting cap plant in upstate New York. The
powder magazines were protected by tall masts according to the "cone of
protection" theory. The angle of the cone varied between 45 and 60
degrees. The earth ground resistance of the mast was measured by a
hand-cranked device that looked like a megger but read earth resistance
to less than a tenth of an ohm. Had the lightning but never lost a
magazine.

You say MIL-HDBK-419 covers EMP. Does it also cover cone of protection
for direct hits?

I was fascinated by the idea that a simple capacitor discharge into an
inductor could be greatly enhanced by reducing the diameter of the
inductor with a conventional explosive, described in one of Stephen
Coonts' books, if my failing memory recalls correctly. And so I learned
what I could about EMP. Never built anything, just interesting behavior.

Best regards,
Bill Hawkins

-----Original Message-----
From: time-nuts [mailto:time-nuts-bounces@febo.com] On Behalf Of Glenn
Little WB4UIV
Sent: Friday, August 05, 2016 9:47 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts]GPS antenna selection - lightning

A very good reference for EMP protection is MIL-HDBK-419.
This is downloadable for a number of web sources.
It is about 600 pages and is in two volumes.
This discusses a number of different sources of EMP such as nuclear and
lightning.
A lot is for protection of military industrial complexes, but, there is
a lot that pertains to us.

I worked for a military complex that assembled nuclear missiles.
The site was built to this handbook specs.
We had no EMP related damage at the site.

Number one rule, bond all grounds together. If something on your
property takes a hit, you want everything on your property to elevate to
the same level and the same rate.
If you have multiple, non bonded grounds, there is a different reference
for each ground. This is a major source for disaster.

I spent seven years in lightning mitigation. I was told by professionals
that I was wrong. The third time that their tower was struck, destroying
all of the lights and attached equipment, they followed my
recommendations. That was ten years ago. The three hits were within four
months of each other. The site has been free of destructive hits since
then.

73
Glenn
WB4UIV

Is the 1987 version the latest issue available for free? ______________________ Clay Autery, KY5G MONTAC Enterprises (318) 518-1389 On 8/6/2016 8:46 AM, Glenn Little WB4UIV wrote: > Cone of protection is addressed. > Volume 1 is theory, volume 2 is application. > The military requires 1/0 cable exterior to the building, commercial > practice is #2AWG. > Ground rod spacing is address. > > Overall a very good reference based on practical experience and backed > with theory. > > 73 > Glenn > WB4UIV > > > On 8/6/2016 1:19 AM, Bill Hawkins wrote: >> Hi Glenn, >> >> Your advice is excellent. >> >> Seems like every time we have a lightning discussion there is no >> distinction between an EMP and a direct hit. >> >> I started work in 1960 at a blasting cap plant in upstate New York. The >> powder magazines were protected by tall masts according to the "cone of >> protection" theory. The angle of the cone varied between 45 and 60 >> degrees. The earth ground resistance of the mast was measured by a >> hand-cranked device that looked like a megger but read earth resistance >> to less than a tenth of an ohm. Had the lightning but never lost a >> magazine. >> >> You say MIL-HDBK-419 covers EMP. Does it also cover cone of protection >> for direct hits? >> >> I was fascinated by the idea that a simple capacitor discharge into an >> inductor could be greatly enhanced by reducing the diameter of the >> inductor with a conventional explosive, described in one of Stephen >> Coonts' books, if my failing memory recalls correctly. And so I learned >> what I could about EMP. Never built anything, just interesting behavior. >> >> Best regards, >> Bill Hawkins >> >> >> -----Original Message----- >> From: time-nuts [mailto:time-nuts-bounces@febo.com] On Behalf Of Glenn >> Little WB4UIV >> Sent: Friday, August 05, 2016 9:47 PM >> To: Discussion of precise time and frequency measurement >> Subject: Re: [time-nuts]GPS antenna selection - lightning >> >> A very good reference for EMP protection is MIL-HDBK-419. >> This is downloadable for a number of web sources. >> It is about 600 pages and is in two volumes. >> This discusses a number of different sources of EMP such as nuclear and >> lightning. >> A lot is for protection of military industrial complexes, but, there is >> a lot that pertains to us. >> >> I worked for a military complex that assembled nuclear missiles. >> The site was built to this handbook specs. >> We had no EMP related damage at the site. >> >> Number one rule, bond all grounds together. If something on your >> property takes a hit, you want everything on your property to elevate to >> the same level and the same rate. >> If you have multiple, non bonded grounds, there is a different reference >> for each ground. This is a major source for disaster. >> >> I spent seven years in lightning mitigation. I was told by professionals >> that I was wrong. The third time that their tower was struck, destroying >> all of the lights and attached equipment, they followed my >> recommendations. That was ten years ago. The three hits were within four >> months of each other. The site has been free of destructive hits since >> then. >> >> 73 >> Glenn >> WB4UIV >> >> >> >> >
CA
Chris Albertson
Sat, Aug 6, 2016 5:13 PM

If you are looking for info in lightening.  University of Florida has a
huge collection and also points to many other places on the web.  They
actually do testing there, lightening occurs so reliably almost every day
in summer.  Their test tower gets many hits
http://www.lightning.ece.ufl.edu

But really, for practical purposes Ben Franklin got it pretty close to
right.  Give the lightening a good low impedance path to ground.

On Sat, Aug 6, 2016 at 8:00 AM, Clay Autery cautery@montac.com wrote:

Is the 1987 version the latest issue available for free?


Clay Autery, KY5G
MONTAC Enterprises
(318) 518-1389

On 8/6/2016 8:46 AM, Glenn Little WB4UIV wrote:

Cone of protection is addressed.
Volume 1 is theory, volume 2 is application.
The military requires 1/0 cable exterior to the building, commercial
practice is #2AWG.
Ground rod spacing is address.

Overall a very good reference based on practical experience and backed
with theory.

73
Glenn
WB4UIV

On 8/6/2016 1:19 AM, Bill Hawkins wrote:

Hi Glenn,

Your advice is excellent.

Seems like every time we have a lightning discussion there is no
distinction between an EMP and a direct hit.

I started work in 1960 at a blasting cap plant in upstate New York. The
powder magazines were protected by tall masts according to the "cone of
protection" theory. The angle of the cone varied between 45 and 60
degrees. The earth ground resistance of the mast was measured by a
hand-cranked device that looked like a megger but read earth resistance
to less than a tenth of an ohm. Had the lightning but never lost a
magazine.

You say MIL-HDBK-419 covers EMP. Does it also cover cone of protection
for direct hits?

I was fascinated by the idea that a simple capacitor discharge into an
inductor could be greatly enhanced by reducing the diameter of the
inductor with a conventional explosive, described in one of Stephen
Coonts' books, if my failing memory recalls correctly. And so I learned
what I could about EMP. Never built anything, just interesting behavior.

Best regards,
Bill Hawkins

-----Original Message-----
From: time-nuts [mailto:time-nuts-bounces@febo.com] On Behalf Of Glenn
Little WB4UIV
Sent: Friday, August 05, 2016 9:47 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts]GPS antenna selection - lightning

A very good reference for EMP protection is MIL-HDBK-419.
This is downloadable for a number of web sources.
It is about 600 pages and is in two volumes.
This discusses a number of different sources of EMP such as nuclear and
lightning.
A lot is for protection of military industrial complexes, but, there is
a lot that pertains to us.

I worked for a military complex that assembled nuclear missiles.
The site was built to this handbook specs.
We had no EMP related damage at the site.

Number one rule, bond all grounds together. If something on your
property takes a hit, you want everything on your property to elevate to
the same level and the same rate.
If you have multiple, non bonded grounds, there is a different reference
for each ground. This is a major source for disaster.

I spent seven years in lightning mitigation. I was told by professionals
that I was wrong. The third time that their tower was struck, destroying
all of the lights and attached equipment, they followed my
recommendations. That was ten years ago. The three hits were within four
months of each other. The site has been free of destructive hits since
then.

73
Glenn
WB4UIV


time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/
mailman/listinfo/time-nuts
and follow the instructions there.

--

Chris Albertson
Redondo Beach, California

If you are looking for info in lightening. University of Florida has a huge collection and also points to many other places on the web. They actually do testing there, lightening occurs so reliably almost every day in summer. Their test tower gets many hits http://www.lightning.ece.ufl.edu But really, for practical purposes Ben Franklin got it pretty close to right. Give the lightening a good low impedance path to ground. On Sat, Aug 6, 2016 at 8:00 AM, Clay Autery <cautery@montac.com> wrote: > Is the 1987 version the latest issue available for free? > > ______________________ > Clay Autery, KY5G > MONTAC Enterprises > (318) 518-1389 > > On 8/6/2016 8:46 AM, Glenn Little WB4UIV wrote: > > Cone of protection is addressed. > > Volume 1 is theory, volume 2 is application. > > The military requires 1/0 cable exterior to the building, commercial > > practice is #2AWG. > > Ground rod spacing is address. > > > > Overall a very good reference based on practical experience and backed > > with theory. > > > > 73 > > Glenn > > WB4UIV > > > > > > On 8/6/2016 1:19 AM, Bill Hawkins wrote: > >> Hi Glenn, > >> > >> Your advice is excellent. > >> > >> Seems like every time we have a lightning discussion there is no > >> distinction between an EMP and a direct hit. > >> > >> I started work in 1960 at a blasting cap plant in upstate New York. The > >> powder magazines were protected by tall masts according to the "cone of > >> protection" theory. The angle of the cone varied between 45 and 60 > >> degrees. The earth ground resistance of the mast was measured by a > >> hand-cranked device that looked like a megger but read earth resistance > >> to less than a tenth of an ohm. Had the lightning but never lost a > >> magazine. > >> > >> You say MIL-HDBK-419 covers EMP. Does it also cover cone of protection > >> for direct hits? > >> > >> I was fascinated by the idea that a simple capacitor discharge into an > >> inductor could be greatly enhanced by reducing the diameter of the > >> inductor with a conventional explosive, described in one of Stephen > >> Coonts' books, if my failing memory recalls correctly. And so I learned > >> what I could about EMP. Never built anything, just interesting behavior. > >> > >> Best regards, > >> Bill Hawkins > >> > >> > >> -----Original Message----- > >> From: time-nuts [mailto:time-nuts-bounces@febo.com] On Behalf Of Glenn > >> Little WB4UIV > >> Sent: Friday, August 05, 2016 9:47 PM > >> To: Discussion of precise time and frequency measurement > >> Subject: Re: [time-nuts]GPS antenna selection - lightning > >> > >> A very good reference for EMP protection is MIL-HDBK-419. > >> This is downloadable for a number of web sources. > >> It is about 600 pages and is in two volumes. > >> This discusses a number of different sources of EMP such as nuclear and > >> lightning. > >> A lot is for protection of military industrial complexes, but, there is > >> a lot that pertains to us. > >> > >> I worked for a military complex that assembled nuclear missiles. > >> The site was built to this handbook specs. > >> We had no EMP related damage at the site. > >> > >> Number one rule, bond all grounds together. If something on your > >> property takes a hit, you want everything on your property to elevate to > >> the same level and the same rate. > >> If you have multiple, non bonded grounds, there is a different reference > >> for each ground. This is a major source for disaster. > >> > >> I spent seven years in lightning mitigation. I was told by professionals > >> that I was wrong. The third time that their tower was struck, destroying > >> all of the lights and attached equipment, they followed my > >> recommendations. That was ten years ago. The three hits were within four > >> months of each other. The site has been free of destructive hits since > >> then. > >> > >> 73 > >> Glenn > >> WB4UIV > >> > >> > >> > >> > > > > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/ > mailman/listinfo/time-nuts > and follow the instructions there. > -- Chris Albertson Redondo Beach, California
GL
Glenn Little WB4UIV
Sat, Aug 6, 2016 7:53 PM

The latest that I can find is 1987.
If you understand the theory and practice, you do not have to update
your work often.
It is the works that are updated every few months that you have to worry
about. The did not get it right the first time.

This is still an active military document.

73
Glenn
WB4UIV

On 8/6/2016 1:13 PM, Chris Albertson wrote:

If you are looking for info in lightening.  University of Florida has a
huge collection and also points to many other places on the web.  They
actually do testing there, lightening occurs so reliably almost every day
in summer.  Their test tower gets many hits
http://www.lightning.ece.ufl.edu

But really, for practical purposes Ben Franklin got it pretty close to
right.  Give the lightening a good low impedance path to ground.

On Sat, Aug 6, 2016 at 8:00 AM, Clay Autery cautery@montac.com wrote:

Is the 1987 version the latest issue available for free?


Clay Autery, KY5G
MONTAC Enterprises
(318) 518-1389

On 8/6/2016 8:46 AM, Glenn Little WB4UIV wrote:

Cone of protection is addressed.
Volume 1 is theory, volume 2 is application.
The military requires 1/0 cable exterior to the building, commercial
practice is #2AWG.
Ground rod spacing is address.

Overall a very good reference based on practical experience and backed
with theory.

73
Glenn
WB4UIV

On 8/6/2016 1:19 AM, Bill Hawkins wrote:

Hi Glenn,

Your advice is excellent.

Seems like every time we have a lightning discussion there is no
distinction between an EMP and a direct hit.

I started work in 1960 at a blasting cap plant in upstate New York. The
powder magazines were protected by tall masts according to the "cone of
protection" theory. The angle of the cone varied between 45 and 60
degrees. The earth ground resistance of the mast was measured by a
hand-cranked device that looked like a megger but read earth resistance
to less than a tenth of an ohm. Had the lightning but never lost a
magazine.

You say MIL-HDBK-419 covers EMP. Does it also cover cone of protection
for direct hits?

I was fascinated by the idea that a simple capacitor discharge into an
inductor could be greatly enhanced by reducing the diameter of the
inductor with a conventional explosive, described in one of Stephen
Coonts' books, if my failing memory recalls correctly. And so I learned
what I could about EMP. Never built anything, just interesting behavior.

Best regards,
Bill Hawkins

-----Original Message-----
From: time-nuts [mailto:time-nuts-bounces@febo.com] On Behalf Of Glenn
Little WB4UIV
Sent: Friday, August 05, 2016 9:47 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts]GPS antenna selection - lightning

A very good reference for EMP protection is MIL-HDBK-419.
This is downloadable for a number of web sources.
It is about 600 pages and is in two volumes.
This discusses a number of different sources of EMP such as nuclear and
lightning.
A lot is for protection of military industrial complexes, but, there is
a lot that pertains to us.

I worked for a military complex that assembled nuclear missiles.
The site was built to this handbook specs.
We had no EMP related damage at the site.

Number one rule, bond all grounds together. If something on your
property takes a hit, you want everything on your property to elevate to
the same level and the same rate.
If you have multiple, non bonded grounds, there is a different reference
for each ground. This is a major source for disaster.

I spent seven years in lightning mitigation. I was told by professionals
that I was wrong. The third time that their tower was struck, destroying
all of the lights and attached equipment, they followed my
recommendations. That was ten years ago. The three hits were within four
months of each other. The site has been free of destructive hits since
then.

73
Glenn
WB4UIV


time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/
mailman/listinfo/time-nuts
and follow the instructions there.

--

Glenn Little                ARRL Technical Specialist  QCWA  LM 28417
Amateur Callsign:  WB4UIV            wb4uiv@arrl.net    AMSAT LM 2178
QTH:  Goose Creek, SC USA (EM92xx)  USSVI LM  NRA LM  SBE ARRL TAPR
"It is not the class of license that the Amateur holds but the class
of the Amateur that holds the license"

The latest that I can find is 1987. If you understand the theory and practice, you do not have to update your work often. It is the works that are updated every few months that you have to worry about. The did not get it right the first time. This is still an active military document. 73 Glenn WB4UIV On 8/6/2016 1:13 PM, Chris Albertson wrote: > If you are looking for info in lightening. University of Florida has a > huge collection and also points to many other places on the web. They > actually do testing there, lightening occurs so reliably almost every day > in summer. Their test tower gets many hits > http://www.lightning.ece.ufl.edu > > But really, for practical purposes Ben Franklin got it pretty close to > right. Give the lightening a good low impedance path to ground. > > On Sat, Aug 6, 2016 at 8:00 AM, Clay Autery <cautery@montac.com> wrote: > >> Is the 1987 version the latest issue available for free? >> >> ______________________ >> Clay Autery, KY5G >> MONTAC Enterprises >> (318) 518-1389 >> >> On 8/6/2016 8:46 AM, Glenn Little WB4UIV wrote: >>> Cone of protection is addressed. >>> Volume 1 is theory, volume 2 is application. >>> The military requires 1/0 cable exterior to the building, commercial >>> practice is #2AWG. >>> Ground rod spacing is address. >>> >>> Overall a very good reference based on practical experience and backed >>> with theory. >>> >>> 73 >>> Glenn >>> WB4UIV >>> >>> >>> On 8/6/2016 1:19 AM, Bill Hawkins wrote: >>>> Hi Glenn, >>>> >>>> Your advice is excellent. >>>> >>>> Seems like every time we have a lightning discussion there is no >>>> distinction between an EMP and a direct hit. >>>> >>>> I started work in 1960 at a blasting cap plant in upstate New York. The >>>> powder magazines were protected by tall masts according to the "cone of >>>> protection" theory. The angle of the cone varied between 45 and 60 >>>> degrees. The earth ground resistance of the mast was measured by a >>>> hand-cranked device that looked like a megger but read earth resistance >>>> to less than a tenth of an ohm. Had the lightning but never lost a >>>> magazine. >>>> >>>> You say MIL-HDBK-419 covers EMP. Does it also cover cone of protection >>>> for direct hits? >>>> >>>> I was fascinated by the idea that a simple capacitor discharge into an >>>> inductor could be greatly enhanced by reducing the diameter of the >>>> inductor with a conventional explosive, described in one of Stephen >>>> Coonts' books, if my failing memory recalls correctly. And so I learned >>>> what I could about EMP. Never built anything, just interesting behavior. >>>> >>>> Best regards, >>>> Bill Hawkins >>>> >>>> >>>> -----Original Message----- >>>> From: time-nuts [mailto:time-nuts-bounces@febo.com] On Behalf Of Glenn >>>> Little WB4UIV >>>> Sent: Friday, August 05, 2016 9:47 PM >>>> To: Discussion of precise time and frequency measurement >>>> Subject: Re: [time-nuts]GPS antenna selection - lightning >>>> >>>> A very good reference for EMP protection is MIL-HDBK-419. >>>> This is downloadable for a number of web sources. >>>> It is about 600 pages and is in two volumes. >>>> This discusses a number of different sources of EMP such as nuclear and >>>> lightning. >>>> A lot is for protection of military industrial complexes, but, there is >>>> a lot that pertains to us. >>>> >>>> I worked for a military complex that assembled nuclear missiles. >>>> The site was built to this handbook specs. >>>> We had no EMP related damage at the site. >>>> >>>> Number one rule, bond all grounds together. If something on your >>>> property takes a hit, you want everything on your property to elevate to >>>> the same level and the same rate. >>>> If you have multiple, non bonded grounds, there is a different reference >>>> for each ground. This is a major source for disaster. >>>> >>>> I spent seven years in lightning mitigation. I was told by professionals >>>> that I was wrong. The third time that their tower was struck, destroying >>>> all of the lights and attached equipment, they followed my >>>> recommendations. That was ten years ago. The three hits were within four >>>> months of each other. The site has been free of destructive hits since >>>> then. >>>> >>>> 73 >>>> Glenn >>>> WB4UIV >>>> >>>> >>>> >>>> >>> >> >> _______________________________________________ >> time-nuts mailing list -- time-nuts@febo.com >> To unsubscribe, go to https://www.febo.com/cgi-bin/ >> mailman/listinfo/time-nuts >> and follow the instructions there. >> > > > -- ----------------------------------------------------------------------- Glenn Little ARRL Technical Specialist QCWA LM 28417 Amateur Callsign: WB4UIV wb4uiv@arrl.net AMSAT LM 2178 QTH: Goose Creek, SC USA (EM92xx) USSVI LM NRA LM SBE ARRL TAPR "It is not the class of license that the Amateur holds but the class of the Amateur that holds the license" ---------------------------------------------------------------------------
CA
Chris Albertson
Sun, Aug 7, 2016 7:30 PM

On Sat, Aug 6, 2016 at 12:53 PM, Glenn Little WB4UIV <
glennmaillist@bellsouth.net> wrote:

The latest that I can find is 1987.
If you understand the theory and practice, you do not have to update your
work often.
It is the works that are updated every few months that you have to worry
about. The did not get it right the first time.

You got that right.  For something as simple as grounding a small antenna
mast if you follow Ben Franklin's advice you will have about the same thing
as what is recommended today.    Same for Newton and Einstein for 99% of
the stuff you do every day Newton got it right.

A lot of the exotic methods invented recently to protect electronics would
not apply to protecting a $50 receiver you bought on eBay or even a $1000
unit.  For example the first thing I would need to do is run a ring of 00
size wire around my house and fuse the various grounds to it.  But the cost
of having the trench dug (before even buying the wire) exceeds the cost of
the equipment it would protect.  TV sets are only $300 today.    So most of
us about $10 worth of protection (a coax ground block and #12 bare wire)
and buy insurance.

Chris Albertson
Redondo Beach, California

On Sat, Aug 6, 2016 at 12:53 PM, Glenn Little WB4UIV < glennmaillist@bellsouth.net> wrote: > The latest that I can find is 1987. > If you understand the theory and practice, you do not have to update your > work often. > It is the works that are updated every few months that you have to worry > about. The did not get it right the first time. You got that right. For something as simple as grounding a small antenna mast if you follow Ben Franklin's advice you will have about the same thing as what is recommended today. Same for Newton and Einstein for 99% of the stuff you do every day Newton got it right. A lot of the exotic methods invented recently to protect electronics would not apply to protecting a $50 receiver you bought on eBay or even a $1000 unit. For example the first thing I would need to do is run a ring of 00 size wire around my house and fuse the various grounds to it. But the cost of having the trench dug (before even buying the wire) exceeds the cost of the equipment it would protect. TV sets are only $300 today. So most of us about $10 worth of protection (a coax ground block and #12 bare wire) and buy insurance. -- Chris Albertson Redondo Beach, California