Re: Chokes vs Safety Gaps

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

Original poster: "gtyler" <gtyler-at-drummond-dot-org.za> 

The NST sedondary has distributed series inductance and also distributed
parallel capacitance, it will act like a transmission line to high freq.
spikes, so you could get the whole spike voltage across a few turns at
the end of the winding. A series inductor should be segmented to reduce
parallel capacitance but you also really need some capacitance across
the NST secondary and also a seristor in series with the choke to kill
the Q so the series resonance is not a problem. I say all this not from
Tesla experience but from general hv electronic design experience, so
there might be more to it, but that's where I would start. The fact that
the secondary has a high inductance is actually apart from the point.

George

----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Tuesday, February 10, 2004 3:19 AM
Subject: Re: Chokes vs Safety Gaps


 > Original poster: "Dr. Resonance" <resonance-at-jvlnet-dot-com>
 >
 >
 > I may be off topic a bit but I still defend a small RF choke before
the RF
 > signal goes into the NST.  Sure the NST has a high inductance and will
 > supress, but it's like letting the fox into the henhouse and then
trying to
 > deal with him.
 >
 > A small RF choke in conjuction with some resistors chokes off the high
 > frequency signals before they get into your xmfr high inductance
 > winding ---- if you let it get into your NST then it causes tracking
and
 > will damage the delicate HV winding while the inductance is trying to
 > supress the HF signal.  The idea is to grab the bad spikes --- before
 > entering your xmfr --- not trying to deal with them once they are
inside the
 > NST and serious tracking and capacitive coupling is occuring.
 >
 > Once they are in the xmfr, as you suggest, sure they are supressed,
but
 > while being suppressed by the large inductance they have to traveling
 > through the windings first, and, unfortunately this can lead to
damage.