Re: Strike object and "Terry Filter"

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Terry Fritz" <teslalist-at-qwest-dot-net>

Hi Jeremy,


At 10:33 PM 6/2/2003 -0400, you wrote:
>Group,
>         Just had a couple of quick questions.  The first question 
> is:  when constructing a strike object, should it be tied to  RF ground, 
> or should it be connected to a separate ground rod in earth?

Either RF type ground is good.  Just not the AC ground.  A separate RF 
ground just for the strike rod would be really nice, but not really needed.

>My second question is regarding the "Terry filter".  What are the purpose 
>of the MOV's in the circuit?  Is it just a safe guard in case a capacitor 
>shorts out?  Will leaving them out make much of difference 
>functionally?  Just thought I would check before making a Digi-key 
>purchase!  Thanks everyone in advance!

"Theoretically", the MOVs do not do anything.  The safety gaps "should" do 
all the work.  Until someone set the safety gaps wrong or a streamer hits 
the circuit or...    The MOVs are really just a last rock solid defense 
against the NST burning out.  MOVs are sort of costly and they do 
occasionally fail too.  But they do provide a secondary wall of defense 
against NST damage.  My NSTs are pretty valuable to me so I will do 
anything to protect them.  If one has a pile of NSTs, then maybe it is not 
such an issue.  But with a properly wired "Terry filter", NST failures are 
practically unheard of.

Cheers,

         Terry




>Jeremy Gassmann
>Cincinnati, Oh
>http://jeremyee.tripod-dot-com
>