I can agree with "All lightning protection must BEGIN outside the structure."
But the fact is we, by the very nature of building a radio station, have
invited lightning inside by virtue of multiple copper paths. Our various
feedlines, rotor control cables, remote antenna switch cables etc..
We have to build a last line of defense inside the shack to deal with, as
effectively as possible, whatever remaining strike potential makes it through
our outside defenses.
Tying those two protection systems together is not inviting the energy
in...it's extending the protection all the way to the equipment we are working
so hard to protect.
Of course there are two camps..I have a friend that believes don't ground
anything...including the tower....that encourages...invites a lightning strike
to occur.
Everybody knows lightning seeks the best path to ground...
I guess the best course is to do what makes one sleep best at night....
Cecil
K5DL
Sent from my iPad
> On May 15, 2014, at 3:49 PM, Robert <rmcgraw@blomand.net> wrote:
>
> All lightning protection must exist outside of the structure.
>
> Do nothing to invite lightning inside unless you desire a lot of damage.
>
> 73
> Bob K4TAX
>
>
>
> Sent from my iPhone
>
>> On May 15, 2014, at 3:39 PM, Brian Carling <bcarling@cfl.rr.com> wrote:
>>
>> AC 3rd pin is not going to be a very effective ground for protection from
>> lightning damage.
>>
>> Best regards - Bry Carling AF4K
>>
>>
>>
>>> On May 15, 2014, at 4:17 PM, Robert <rmcgraw@blomand.net> wrote:
>>>
>>> Braid is not the best choice for a low inductance RF path. It is although
>>> necessary for flexible applications.
>>>
>>> Personally I bond all equipment to the station supply and do not use
>>> anything but the AC 3rd pin for safety reasons.
>>>
>>> 73
>>> Bob, K4TAX
>>>
>>>
>>>
>>> Sent from my iPhone
>>>
>>>>> On May 15, 2014, at 2:20 PM, Carter <k8vt@ameritech.net> wrote:
>>>>>
>>>>> On 5/14/2014 5:56 PM, Stuart Rohre wrote:
>>>>> Some Yaecomwoods do suffer from RF entering the rig.
>>>>>
>>>>> MOST ANY rig will if you have a bad shield connection on coax jumper, or
>>>>> have rig too close to the antenna, (second floor shack), and there are
>>>>> many other rig and feedline issues to rule out in any RFI case.
>>>> True, can be many causes, but I am in a basement shack. Also, a few years
>>>> ago, I used a Drake TR-7 on SSB with everything else the same and it
>>>> worked fine. However, I realize that the TR-7 was not as "computerized"
>>>> (dependent on microprocessors) as the Omni VI.
>>>>>
>>>>> Rule of thumb: Power all equipment from same circuit breaker of the
>>>>> house. That ensures AC grounds will not be coming from widely different
>>>>> locations. IF you have to use a long ground wire for lightning
>>>>> protection ground on the station (like from second floor shack), consider
>>>>> that it could act as an "antenna" for pick up of RF from the real
>>>>> antenna. You may need tuned radials, or a radial for each favorite band.
>>>> Good tip and I believe I am on the same breaker for all the ham equipment.
>>>> Again, a basement shack and 5 or 6 feet of a single 3/4 inch wide braid
>>>> from the ground of each piece of equipment to the ground rod right on the
>>>> outside of the basement wall.
>>>>>
>>>>> You could always examine the quality of the grounding of the mike cable
>>>>> shield. Some older mike cords had just a multi-strand wire wrapped in
>>>>> one direction and not a hatch pattern wire shield. Some aluminum foil
>>>>> shields don't make a good low impedance connection by clamping.
>>>>> (Connections that can't be soldered are suspect).
>>>>
>>>> Should have mentioned this earlier, but back in the day before I used any
>>>> computer interface, I had the problem with both a TT 705(?) mic and a Heil
>>>> Pro headset. Probably unlikely that both were defective.
>>>>
>>>> 73,
>>>> Carter K8VT
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