On Feb 15, 12:43*pm, bpnjensen wrote:
On Feb 15, 9:08*am, Bob Dobbs wrote:

dave wrote:

http://www.mfjenterprises.com/pictures/MFJ-270.jpg

Looks like the gas discharge type I have.
Somewhere I heard someone say that they go shorted when hit,
like a MOV, but that seems counterintuitive and it seems more likely
that they would just go permanently open by out gassing.
What's your opinion on this?

My DX-Ultra has a proprietary gas discharge arc-plug in its core.
Alpha Delta says that after several years of significant static, it
can get weak and the antenna won't function as well. *Just to be anal,
I put in a new one about 6 years ago, and it's worked about the same
before and after and ever since.

On the subject of front end protection. Some very good (old-time)
designs contained a simple neon light (120vac) across the antenna
terminals . Such modestly priced extra protection never hurts . Gas
discharge tube type is much better,though .