Lightning Arrestor for Ladder Line

[David, K3TUE]

I wish to add some lightneing arrestor technology (<<a href=http://www.alphadeltacom.com/tt3g50.html>http://www.alphadeltacom.com/tt3g50.html</a>>, <<a href=http://www.rflinx.com/products/lightning-arrestors/>http://www.rflinx.com/products/lightning-arrestors/</a>>) to my antenna system in addition to a short-to-ground knife switch.  But I will be feeding with ladder line, and these are made for coax.

I was reading on the web about someone who uses non-resistor spark plugs to accomplish this (<<a href=http://www.athensarc.org/ladder.htm>http://www.athensarc.org/ladder.htm</a>>).  While I am unsure of the real security offered by such an idea, it got me to thinking that perhaps I could just run each leg of the ladder line through the center feeder of a coaxial lightning arrestor.

Can anyone out there assure me for or warn me against such an idea?

[k7yoo]

My thought is why let a charge build up in the first place?
I use a choke from each leg of the ladder line to ground--NO static buildup.
The particular chokes I am using now look very much like Valiant plate chokes. In the past I have used National R-175 chokes.
Skip

[David, K3TUE]

My thought is why let a charge build up in the first place?
I use a choke from each leg of the ladder line to ground--NO static buildup.

This is interesting, as I was thinking today, I can't imagine a lightening arrestor actually saving your home/equipment in the event of a direct strike.  So it seems that "Lightening Arrestors" protect you from charges induced into your antenna system due to near/not-so-near strike induction and static charge built up from wind and the like.

I can see how the choke would bleed a charge to ground and not pass rf ac to ground (being an inductor).

Is it really that simple?

[WA2IXP]

Dave, I think the coax arrestors might arc under normal use even at low power if swr was high and voltage peak was near that point in line. Rf chokes good idea if your tuner doesn't have a dc path to ground  for static. Knife switch and a prayer might offer minimal protection from direct strike but I doubt it. Jay-

[WA1GFZ]

My antenna tuner is at DC ground but it will flash over during a storm with a close strike. Take 3 ceramic standoffs and make the center one ground. Take 3 hunks of copper and set up spark gaps so they don't flash over during normal operation.
This is shown in many old handbooks.

[W1IA]

My thought is why let a charge build up in the first place?
I use a choke from each leg of the ladder line to ground--NO static buildup.
The particular chokes I am using now look very much like Valiant plate chokes. In the past I have used National R-175 chokes.
Skip

Why that fancy? I used a couple of 2 meg resistors to ground to bleed static from my loop ant.
Brent

[Steve W8TOW]

Go to:
http://www.arraysolutions.com/Products/ice/3.html

I use the lightning protection for ladder line made by ICE.
It uses a choke on each leg to bleed off the static and there are gas discharge
units in it too. (Plus some big caps)
Their product is pretty impressive, Once upon a time, suing their product on a
20m monobander at 80', I took a direct hit. The coax "N" connectors at the antenna were
damaged, but the rigs (by my neglect) had been left connected to the antenna.
The rigs were fine.
Tho I now disconnect my antenna's when not at home!
73 steve

[Todd, KA1KAQ]

I've heard that their stuff is good, Steve. Never realyl thought that much of anything was desgined to actually protect from a direct hit, more to prevent it from happening by draining off the charge before it can build up to potential.

The spark plug thing should work, although setting the correct gap could be fun. I remember seeing in the back of some transmitter manuals (Collins comes to mind) a design for a 'horn gap' using copper tubing bent to a certain shape and arranged with a similar gap. Looked cool as hell, but not something you'd throw together in 15 minutes.

Anytime your equipment survives a strike, you are very lucky in my opinion. Years ago I had a hybrid rig that suddenly went numb after a nearby (1/4 mile or so) strike. The tubes were all fine, but some ot the sand-state components were fried. And it wasn't hooked to the antenna, though it still had a coax jumper attached. Apparently that was enough.

Drain the charge before it can ever build up an attractive little step leader, that's the best plan. And unhook/ground stuff when not in use, or course.

[Steve W8TOW]

Righto, drain the charge...
I think, I might be wrong, but the idea ICE has by using the
choke to ground on each leg of the Feeders is to do just that...
In their coaxial version of the product, they use a swinging choke.
I'd be surprised if they do anything different in this product...
gl es 73 steve