[TenTec] OT: Lightening Protection for Openwire/Window Line

[Richards]

Interesting answers...

I am wary of any solution that leaves transmission lines loose and 
ungrounded.  I have seen how lightning can arc from a disconnected cable 
across a desk and zap a radio. It my friend's SWL installation, but I 
doubt lightning cared what sort of radio it is toasting.

Thus, I am skeptical bout just opening a knife switch on the wall and 
not grounding the wires in some way.  I am even a little worried about 
Joel's balanced arrestor acting alone on an unterminated (open) knife 
switch.  I would ALSO ground the two wires on a buss bar.   (See Wireman 
857 and 858 - which I use.)

	I really like Stuart's notion of a double throw
	knife switch that grounds both sides when off
	the air.
	
Coax enters my shack via 8 inch bulk head connectors.  I use a properly 
rated and grounded arrestor outside, and all disconnected lines are 
routed to a buss bar with extremely short RG-213 patch cables (using the 
same push on connectors Joel mentioned.)  My theory is I can disconnect 
all my antennas and ground them directly, and separately, from the 
radios. The support masts are also grounded - and all grounds are bonded 
together - using four (4),  8-ft ground rods located about 4 to 6 feet 
from each other, they are all about 6 feet from the shack coax entry point.

My remote coax switch is grounded to this set of grounds, as well.  I 
switch the system to the dummy load when I close the station.  I 
disconnect the radios and patch the inside bulk head connector to the 
grounded buss bar - so any energy that gets past the outside arrestor 
(connected to the four ground stakes) is routed to the grounded buss bar 
and directed back outside, again to the four stakes.  My only concern is 
that I may have created a ground loop that causes me problems, but so 
far, no problems.

As per above, I would never leave a disconnected wire or cable loose and 
ungrounded (disconnected)-- all unused lines are routed directly to the 
grounded buss bar with a very short, heavy patch cable.   I use screw on 
connectors for HF antennas, and push on connectors for the SWL and VHF 
scanner antennas as I think the screw type provide better (tighter) and 
more positive electrical connection.  (K4TAX taught me about snugging up 
connections early on...)

Just My take, anyway.

-------------------- K8JHR  --------------------

On 7/30/2013 9:39 AM, Joel Hallas wrote:
> While knife switches have been popular over the years, the big ones with
> wide spacing are hard to find. My approach is to have a balanced arrestor at
> the entrance panel and then I have 3/4 inch spaced banana plug and jack
> between the arrestor and the line to the tuner. When I'm not on the air with
> that antenna, it is pulled out and feet away from anything.
>
> The only balanced transmit level arrestors I'm aware of in recent years have
> been from ICE and mine is one of their earlier series. Their arrestor line
> is handled by array solutions and they now have a new design
> http://www.iceradioproducts.com/. It is also possible to use a pair of coax
> type arrestors, but determine the voltage at that point on each band due to
> SWR and make sure that you select arrestors that won't flashover with the
> RF.
>
> I use a similar approach for coax fed antennas. I have arrestors on the
> grounded panel and then use PL-259 push on adapters on the radio side. One
> yank and they're all well removed.
>
>  _______________________________________________