[time-nuts] Thoughts on lightning protection measures....

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A very efficient solution would be to get the signal/power conducting 
cables out of the lightning path - that means a GPS receiver near the 
antenna, with a local power supply (photo cell panels / buffer 
accumulator) and signal transmission over optical fiber. Quite feasible, 
as a GPS Rx has low power requirements.
If the delay from receiver to the disciplined oscillator is critical, or 
too high, a compensation scheme comes to mind - 2 identical optical 
paths in a loop, with the sent pps signal phase adjusted so that the 
received GPS pps is centered between the sent and the looped one.

Regarding the TBs, even if they are the only ones directly connected to 
the antenna, the cable is already punching through the house Faraday 
cage, and chances are quite high that the lightning discharge won't stop 
at them.


On 4/12/2012 5:03 PM, Azelio Boriani wrote:
> I have 2 TBolts but now I'm thinking to buy others to save them from the
> sacrifice...
>
> On Thu, Apr 12, 2012 at 3:58 PM, Jim Lux<jimlux at earthlink.net>  wrote:
>
>> On 4/12/12 6:22 AM, Michael Baker wrote:
>>
>>> Time-nutters--
>>>
>>> Around here (N. Central Flori-DUH) it is not uncommon for
>>> near-by lightning strikes to damage underground cables and
>>> wiring. This is why buried wiring to things like driveway
>>> gate-openers are often placed in conduit rather than done
>>> with direct-burial wiring so that if lightning damages the
>>> wiring a new cable can be pulled through the conduit without
>>> having to re-dig the burial trench.
>>>
>>> Some years ago I had occasion to hold some long discussions
>>> with Martin Uman, one of the worlds most distinguished and
>>> eminent lightning researchers. He commented that even with
>>> the most extraordinary and costly efforts to install protection
>>> measures, that-- sooner or later-- there was a good chance that
>>> lightning would find a way to damage things.
>>>
>>>
>>
>> Dr. Uman (and his colleague Dr. Rakov) probably know about lightning and
>> effects than any other humans alive.   He's making an excellent point: at
>> some point, the cost to replace the gear (or the cost of being "off the
>> air") is smaller than the cost of the protection scheme.
>>
>> Sometimes, you're better off having a sacrificial element, and a spare in
>> the closet for speedy repair.
>>
>>
>>   His lightning research laboratory was located here in
>>> N.Central Florida because it is in the heart of the most
>>> dense strike area in N. America.
>>>
>>
>>
>>
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