Re: [Elecraft] Automatic lightning protection for radios, .... an off the wall idea

[Jim Brown]

On 1/19/2021 7:08 AM, Louandzip via Elecraft wrote:

  there are quite a few.


Last I looked (retired 10 years), there were two in the US, UL and ETL, 
and CSA in Canada. There were reciprocal agreements between UL and CSA, 
and UL, CSA, and ETL were recognized in the US. That's not "quite a 
few," unless we include those on other continents.


73, Jim K9YC
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Re: [Elecraft] Automatic lightning protection for radios, an off the wall idea

[Bill Frantz]

I also received a link to:

 which is also an 
antenna disconnect. Note that the web page is in German, but you 
can download an English version of the manual.


A device that only disconnects the antenna fixes only part of 
the problem. What I would really like is a box that covers all 
the radio's connections.


It may not be necessary to cover all the connections. Elecraft 
support probably has a good idea of what in the radio survives 
nearby lightning strikes and what dies.


73 Bill AE6JV

On 1/19/21 at 10:35 AM, joe_a...@yahoo.com (Joe Pugliano) wrote:


Check out this Paradan antenna disconnect.
Paradan Radio Antenna Disconnect Actuators P-ADA-1


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do good for

408-348-7900   |an evolved body of kludges" - Mark Miller
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Re: [Elecraft] Automatic lightning protection for radios, .... an off the wall idea

[Louandzip via Elecraft]

 It's been quite a while since I worked in the biz, but IIRC, UL is a NRTL, 
"Nationally Recognized Testing Laboratory."  They don't approve devices per se, 
but rather certify a device passed statutory safety standard testing.  A 
certification only means samples and manufacturing process passed the specific 
tests. Other NRTLs can do the same, and there are quite a few. A manufacturer 
needs to have their products certified by an NRTL if fed, state, or local 
regulations require it, or customers (often large entities) require it.  At the 
time I was in the biz, "harmonization" was going on, that was bringing all the 
disparate standards of various entities into alignment.  IDK what the current 
situation is. 

I'm sure there are more knowledgeable and current guys on this reflector. 
On Tuesday, January 19, 2021, 5:03:58 AM MST, Rich NE1EE 
 wrote:  
 
 On 2021-01-18 20:23:-0600, Jim Borowski wrote:
>Did I read this right regulation connector?If the clamps on the ground rod, or 
>water pipe, it is not UL stamped, it's not approved.Jim K9TFSent from my 
>T-Mobile 4G LTE Device

Unfortunately,
the email footnotes don't include a link to the archive thread, and
there is no context, so I don't know to whom you reply...

but I am part of the thread, so I'll clarify for my part.
the loose connectors are UL listed. Two were loose, and 1 was incorrectly 
installed. I actually saw a web page that showed //an incorrect installation// 
as part of a "help page". I sent them a note, but didn't follow up.

Ah! Had not used nabble in the past, and I now see that this is in response to 
Bob McGraw - K4TAX, but the context is not clear.

~R~
72/73 de Rich NE1EE
The Dusty Key
On the banks of the Piscataqua

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Re: [Elecraft] Automatic lightning protection for radios, .... an off the wall idea

[Rich NE1EE]

On 2021-01-18 20:23:-0600, Jim Borowski wrote:
>Did I read this right regulation connector?If the clamps on the ground rod, or 
>water pipe, it is not UL stamped, it's not approved.Jim K9TFSent from my 
>T-Mobile 4G LTE Device

Unfortunately,
the email footnotes don't include a link to the archive thread, and
there is no context, so I don't know to whom you reply...

but I am part of the thread, so I'll clarify for my part.
the loose connectors are UL listed. Two were loose, and 1 was incorrectly 
installed. I actually saw a web page that showed //an incorrect installation// 
as part of a "help page". I sent them a note, but didn't follow up.

Ah! Had not used nabble in the past, and I now see that this is in response to 
Bob McGraw - K4TAX, but the context is not clear.

~R~
72/73 de Rich NE1EE
The Dusty Key
On the banks of the Piscataqua

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Re: [Elecraft] Automatic lightning protection for radios, .... an off the wall idea

[Jim Borowski]

Did I read this right regulation connector?If the clamps on the ground rod, or 
water pipe, it is not UL stamped, it's not approved.Jim K9TFSent from my 
T-Mobile 4G LTE Device
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Re: [Elecraft] Automatic lightning protection for radios, .... an off the wall idea

[Jim Brown]

On 1/18/2021 11:53 AM, hb9...@hispeed.ch wrote:

MOV can be used even in AC power applications (50/60Hz) , but only if the
potential thermal run away effect ( drawing more leakage current after
energy absorption/exposure or by aging ) is controlled by a series connected
high impedance (no-fire mode)  spark gap. What is however critical under
non-fire RF conditions (MOV -ZnO has big nF capacitance and is a
semiconductor) is the nonlinear diode effect. This can lead to RF
rectification (harmonics, emission issue)  before the firing level is
reached.


There's FAR more to it that these issues. The problems include 1) where 
they dump the current when they short out a strike; 2) accumulation of 
discharge current over time degrades their performance, causing them to 
fail shorted or open; and 3) they can start a fire! When an MOV shorts 
the strike to the equipment ground ("green wire") it raises the chassis 
potential of connected equipment; when that equipment is connected to 
other equipment by "low voltage" wiring (audio or video cables, Ethernet 
or other computer cables) to equipment plugged into different outlets 
(or even a different MOV device), the potential difference between the 
two pieces of gear is likely to fry I/O circuitry.


Many years ago, we in the world of pro audio learned this, with 
equipment for large audio (that sometimes included video systems) spread 
out over wide areas. As long ago as the '90s, very well-educated EEs 
recounted stories of computers in their design offices networked by 
wired Ethernet being fried by lightning induced on the Ethernet cables 
and computers with MOV surge protectors. No intentional antennas 
involved (not hams).


All of this is a great reason for using WiFi rather than wired Ethernet 
unless the added latency of WiFi cannot be tolerated (remote operation, 
for example). I dumped the use of wired Ethernet a couple of years 
before moving from Chicago in 2006. Decent WiFi hardware provides plenty 
of bandwidth for my uses, including streaming audio and hi-res streamed 
compressed video.


73, Jim K9YC
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Re: [Elecraft] Automatic lightning protection for radios, .... an off the wall idea

[hb9cvq]

Yes, Jim,  but:  "It's also the kind of destructive failure that the use of
MOV surge protectors can CAUSE".

MOV can be used even in AC power applications (50/60Hz) , but only if the
potential thermal run away effect ( drawing more leakage current after
energy absorption/exposure or by aging ) is controlled by a series connected
high impedance (no-fire mode)  spark gap. What is however critical under
non-fire RF conditions (MOV -ZnO has big nF capacitance and is a
semiconductor) is the nonlinear diode effect. This can lead to RF
rectification (harmonics, emission issue)  before the firing level is
reached.

73 Andy HB9CVQ


-Original Message-
From: elecraft-boun...@mailman.qth.net  On
Behalf Of Jim Brown
Sent: Montag, 18. Januar 2021 19:16
To: elecraft@mailman.qth.net
Subject: Re: [Elecraft] Automatic lightning protection for radios,  an
off the wall idea

On 1/18/2021 9:09 AM, Bill Frantz wrote:
> While serious lightning protection for structures and other robust 
> things must be done outside the building, I have heard reports of K3S 
> USB chips being fried from currents induced in the USB cable attached 
> to the radio, with the suggestion of disconnecting the cable to 
> protect the chip. I don't see how to do this disconnect outside the
building.

Right. That is the kind of failure that proper grounding and bonding are
able to protect against. It's also the kind of destructive failure that the
use of MOV surge protectors can CAUSE.

> When I consider a direct strike on my shack's lighting rods, I see 
> massive currents flowing down the thick aluminum cables from the rods 
> to the grounding system. I see these currents inducing currents in any 
> wires in the house, including the USB cable. The lightning rods are 
> the first level of protection, but may not be enough to protect 
> sensitive electronic equipment. Remember, when we work on these 
> radios, we have a grounding wrist strap and a conductive mat on the work
surface etc.

That's another thing the proper grounding and bonding protect against. 
But lightning induces current not only on that external wiring, but also
wiring within the building. IEEE studies show that up to 3kV can be induced
on internal wiring by a strike!

73, Jim K9YC
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Re: [Elecraft] Automatic lightning protection for radios, an off the wall idea

[Charles Hardt]

I would not want a high static discharges such as a lightning near miss in my 
K4 or any radio I have.  Nor would I want it in my house.  I am thinking of 
antennas discharge.

IMHO, 
& 73,
Charlie, N2PKW 

-Original Message-
From: elecraft-boun...@mailman.qth.net  On 
Behalf Of Bill Frantz
Sent: Sunday, January 17, 2021 9:34 PM
To: Elecraft Reflector 
Subject: [EXT]: [Elecraft] Automatic lightning protection for radios, an off 
the wall idea

I've been thinking about some kind of automatic lightning protection for 
radios, specifically ones like the K3 and K4. The idea is that when you turn 
the radio off, all the things that are subject to damage are protected by 
disconnecting them from the external world and shorting their inputs to ground.

This approach probably wouldn't protect against a direct hit to one of the 
wires coming into the radio, which are most likely on the antenna input and the 
power from a solar system. But I understand that the most significant part of 
the problem is voltage spikes introduced when the external wires act as 
antennas and pick up nearby lightning strikes.

I'm not a hardware engineer, so I'm going to assume that relays are used in 
this device. Some of the things I see this device doing are:

USB connection: Elecraft tells us that blown USB chips are one of the more 
common forms of lightning damage in the K3. There are 4 wires in the USB 
interface, two of which carry power from the external world. The relay(s) would 
float the USB wires and ground the connections to the internal USB chip. Since 
power from the external world is present when the radio is off, we can't ground 
the power leads, although we can ground the power input to the radio's USB chip.

Note that currently a computer attached to the K3 can see its USB chip, even 
when the radio is turned off. This change would mean that the computer would no 
longer see the radio over USB, which might have annoying software effects.

A similar thing could happen to the antenna inputs.

Key/Paddle, microphone, headphones, RS232, etc. would be treated the same way.

The AUXbus would be treated similarly, but anything that can be turned on via 
the AUXbus would need special handling.

The 12V power input is needed to turn the radio on with the power button. I 
don't know how often radios are damaged through their 12V power input. This 
input may not need protection. 
Otherwise, the relay that protects power and the switch to the radio could be 
the only things powered when the radio is off. If it can't be protected, it 
could be made easily field replaceable.

It would be neat if there's enough room inside a K4 to put this kind of 
protection "under the covers".

73 Bill AE6JV

---
Bill Frantz| The race is not always to the swift, nor 
the |
(408)348-7900  | battle to the strong, but that's the way to 
bet. |
www.pwpconsult.com |   - Damon 
Runyon |

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Re: [Elecraft] Automatic lightning protection for radios, .... an off the wall idea

[Jim Brown]

On 1/18/2021 9:12 AM, Rich NE1EE wrote:

After I installed my ground grid, the last step was to connect to the house 
grounds. There were 3 of them, and every one was loose on the ground rod. They 
all appeared to be regulation listed connectors, but poorly installed. Glad I 
was there to find that.


Electrical wiring, including grounding, was a mess at the home we bought 
in NorCal in 2006. I found multiple mis-wired outlets, including several 
in a laundry room/half kitchen fed by phase (hot) and ground from the 
240V circuit for the adjacent dryer.


That was in a garage/apartment which now houses my shack; power enters 
the house, and is fed to a breaker panel in the second building. The 
house had no ground at all -- a #10-#12 (painted) bare copper wiring ran 
from the service entrance panel to an outlet for a garden hose, which 
was fed by PVC pipe. The ground for the panel in the second building 
wandered from the panel up to and through the attic crawl space to the 
other side of the building, then run neatly down the outside wall next 
to the facings for windows to a ground rod. It was the only ground for 
the entire system.


73, Jim K9YC
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Re: [Elecraft] Automatic lightning protection for radios, .... an off the wall idea

[Jim Brown]

On 1/18/2021 9:09 AM, Bill Frantz wrote:
While serious lightning protection for structures and other robust 
things must be done outside the building, I have heard reports of K3S 
USB chips being fried from currents induced in the USB cable attached to 
the radio, with the suggestion of disconnecting the cable to protect the 
chip. I don't see how to do this disconnect outside the building.


Right. That is the kind of failure that proper grounding and bonding are 
able to protect against. It's also the kind of destructive failure that 
the use of MOV surge protectors can CAUSE.


When I consider a direct strike on my shack's lighting rods, I see 
massive currents flowing down the thick aluminum cables from the rods to 
the grounding system. I see these currents inducing currents in any 
wires in the house, including the USB cable. The lightning rods are the 
first level of protection, but may not be enough to protect sensitive 
electronic equipment. Remember, when we work on these radios, we have a 
grounding wrist strap and a conductive mat on the work surface etc.


That's another thing the proper grounding and bonding protect against. 
But lightning induces current not only on that external wiring, but also 
wiring within the building. IEEE studies show that up to 3kV can be 
induced on internal wiring by a strike!


73, Jim K9YC
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Re: [Elecraft] Automatic lightning protection for radios, .... an off the wall idea

[Bill Frantz]

To add to what I just posted, Wayne just posted a link to a K4 
manual that states:


ESD and Lightning Protection: Even though the the K4 has 
extensive internal protective circuitry, external protection 
against lightning strikes is strongly recommended, especially in 
lightning-prone areas. During storms and when the station is not 
in use for an extended period, disconnect ALL equipment from the 
radio, including antennas, the power supply, routers or hubs, 
and computers. Ethernet, USB, and RS232 cables are a frequent 
source of damaging surge voltages.


73 Bill AE6JV

---
Bill Frantz| gets() remains as a monument | Periwinkle
(408)348-7900  | to C's continuing support of | 150 
Rivermead Rd #235
www.pwpconsult.com | buffer overruns. | 
Peterborough, NH 03458



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Re: [Elecraft] Automatic lightning protection for radios, .... an off the wall idea

[Rich NE1EE]

On 2021-01-18 10:38:-0600, Bob McGraw wrote:

>Just remember that ALL lightning protection must be accomplished outside of 
>the house or structure.�  Do not think for one minute that one can provide 
>lightning protection inside the equipment or structure.

...and I just last summer discovered another reason to do this...After I 
installed my ground grid, the last step was to connect to the house grounds. 
There were 3 of them, and every one was loose on the ground rod. They all 
appeared to be regulation listed connectors, but poorly installed. Glad I was 
there to find that.

~R~
72/73 de Rich NE1EE
The Dusty Key
On the banks of the Piscataqua

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Re: [Elecraft] Automatic lightning protection for radios, .... an off the wall idea

[Bill Frantz]

While serious lightning protection for structures and other 
robust things must be done outside the building, I have heard 
reports of K3S USB chips being fried from currents induced in 
the USB cable attached to the radio, with the suggestion of 
disconnecting the cable to protect the chip. I don't see how to 
do this disconnect outside the building.


When I consider a direct strike on my shack's lighting rods, I 
see massive currents flowing down the thick aluminum cables from 
the rods to the grounding system. I see these currents inducing 
currents in any wires in the house, including the USB cable. The 
lightning rods are the first level of protection, but may not be 
enough to protect sensitive electronic equipment. Remember, when 
we work on these radios, we have a grounding wrist strap and a 
conductive mat on the work surface etc.


73 Bill AE6JV

On 1/18/21 at 11:38 AM, rmcg...@blomand.net (Bob McGraw) wrote:

Just remember that ALL lightning protection must be 
accomplished outside of the house or structure.  Do not think 
for one minute that one can provide lightning protection inside 
the equipment or structure.


---
Bill Frantz| gets() remains as a monument | Periwinkle
(408)348-7900  | to C's continuing support of | 150 
Rivermead Rd #235
www.pwpconsult.com | buffer overruns. | 
Peterborough, NH 03458


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Re: [Elecraft] Automatic lightning protection for radios, an off the wall idea

[Jim Brown]

This is VERY good advice. The most important thing we can do to minimize 
lightning damage is to seriously implement proper grounding and bonding 
in our stations and throughout our homes. N0AX's ARRL Book on the topic 
is a great reference; I collaborated with him on it. Also study the 
slides for talks I've done at west coast hamfests. Don't let the word 
"audio" in the link fool you. This is about EVERY element of grounding 
and bonding specifically for ham radio.


http://k9yc.com/GroundingAndAudio.pdf

Another VERY important thing is to NEVER use shunt mode (MOV) type surge 
protectors anywhere except at the Service Entrance (where power enters 
the building). MOVs are more likely to CAUSE destructive failure than to 
prevent it.


Surge-X, Brick Wall, and a third company whose name I've forgotten make 
series-mode surge protectors. They're more expensive, but a LOT cheaper 
than our radios. There's a brief discussion of series-mode vs shunt mode 
beginning on page 28 of this link


http://k9yc.com/SurgeXPowerGround.pdf

A far more extensive discussion begins with slide #69 in this link. It's 
by Andy Benton, a very good engineer who designed the Surge-X products. 
This is the first part of a 4-hour talk that Andy and I did at 
conventions for companies designing and installing professional audio 
and video systems in public buildings and for corporate operations.


http://k9yc.com/InfoComm-PowerSystems2012.pdf

My good friend Bill is right on about very high currents and voltages 
being induced on wiring inside our homes. In addition to antennas, 
lightning comes in on power lines, telephone lines, and CATV lines.


Finally, I want to emphasize what I said at the start about doing this 
VERY seriously. Lightning has a way of finding things we didn't do.


73, Jim K9YC

On 1/17/2021 9:19 PM, hb9...@hispeed.ch wrote:

I think we need to divide protection into different topologies/ barriers/
zones. This is  according to threat phenomena ( e.g. xxx kilo Amps to milli
Amps and smaller ).

Threat levels need to be reduced step by step  and systematically.
Surge Limiters / Filtering / Shielding / System Layout with minimizing
coupling effects are part of this.

Protection against any threat level ( EMI energy / current / voltage /EM
field derivatives)  can/should realistically and economically not be
implemented just finally at the radio itself.

Lightning is first of all a more external system problem (Tower / Station
Single Entry Panel Point / Cable- Layout, loop, spark over voltage /
conductor melting/welding...).
While lower threat levels, like adverse subsystem (shack) coupling of
transients / continuous waves etc. -EMI/ESD Immunity- are certainly part of
the good EMC radio/design .

Professional EMC Standards (EU-HAM Radio, EN ETSI  301783...

https://www.etsi.org/deliver/etsi_en/301700_301799/301783/02.01.01_60/en_301
783v020101p.pdf


and specific System Experiencehttp://k9yc.com/publish.htm   -also from big
contest stations-  tell you what to do in HAM Radio electronics.


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Re: [Elecraft] Automatic lightning protection for radios, an off the wall idea

[hb9cvq]

Hi Bill,

Just a general remark:

I think we need to divide protection into different topologies/ barriers/
zones. This is  according to threat phenomena ( e.g. xxx kilo Amps to milli
Amps and smaller ).

Threat levels need to be reduced step by step  and systematically.
Surge Limiters / Filtering / Shielding / System Layout with minimizing
coupling effects are part of this.

Protection against any threat level ( EMI energy / current / voltage /EM
field derivatives)  can/should realistically and economically not be
implemented just finally at the radio itself.

Lightning is first of all a more external system problem (Tower / Station
Single Entry Panel Point / Cable- Layout, loop, spark over voltage /
conductor melting/welding...).
While lower threat levels, like adverse subsystem (shack) coupling of
transients / continuous waves etc. -EMI/ESD Immunity- are certainly part of
the good EMC radio/design .

Professional EMC Standards (EU-HAM Radio, EN ETSI  301783...

https://www.etsi.org/deliver/etsi_en/301700_301799/301783/02.01.01_60/en_301
783v020101p.pdf


and specific System Experience http://k9yc.com/publish.htm  -also from big
contest stations-  tell you what to do in HAM Radio electronics.


Tnx, Cu, vy 73 de Andy
HB9CVQ, DK2VQ, AK4IG

https://www.qrz.com/db/HB9CVQ


-Original Message-
From: elecraft-boun...@mailman.qth.net  On
Behalf Of Bill Frantz
Sent: Montag, 18. Januar 2021 04:34
To: Elecraft Reflector 
Subject: [Elecraft] Automatic lightning protection for radios, an off the
wall idea

I've been thinking about some kind of automatic lightning protection for
radios, specifically ones like the K3 and K4. The idea is that when you turn
the radio off, all the things that are subject to damage are protected by
disconnecting them from the external world and shorting their inputs to
ground.

This approach probably wouldn't protect against a direct hit to one of the
wires coming into the radio, which are most likely on the antenna input and
the power from a solar system. But I understand that the most significant
part of the problem is voltage spikes introduced when the external wires act
as antennas and pick up nearby lightning strikes.

I'm not a hardware engineer, so I'm going to assume that relays are used in
this device. Some of the things I see this device doing are:

USB connection: Elecraft tells us that blown USB chips are one of the more
common forms of lightning damage in the K3. There are 4 wires in the USB
interface, two of which carry power from the external world. The relay(s)
would float the USB wires and ground the connections to the internal USB
chip. Since power from the external world is present when the radio is off,
we can't ground the power leads, although we can ground the power input to
the radio's USB chip.

Note that currently a computer attached to the K3 can see its USB chip, even
when the radio is turned off. This change would mean that the computer would
no longer see the radio over USB, which might have annoying software
effects.

A similar thing could happen to the antenna inputs.

Key/Paddle, microphone, headphones, RS232, etc. would be treated the same
way.

The AUXbus would be treated similarly, but anything that can be turned on
via the AUXbus would need special handling.

The 12V power input is needed to turn the radio on with the power button. I
don't know how often radios are damaged through their 12V power input. This
input may not need protection. 
Otherwise, the relay that protects power and the switch to the radio could
be the only things powered when the radio is off. If it can't be protected,
it could be made easily field replaceable.

It would be neat if there's enough room inside a K4 to put this kind of
protection "under the covers".

73 Bill AE6JV

---
Bill Frantz| The race is not always to the swift, nor 
the |
(408)348-7900  | battle to the strong, but that's the way to 
bet. |
www.pwpconsult.com |   - Damon 
Runyon |

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