Re: LTR, STR ?

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: "David Rieben" <drieben@xxxxxxxxxxxxxxx>

Robert,

LTR- Larger Than Resonant
STR- Smaller Than Resonant

Resonance refers to the capacitance size of the primary capacitor as 
is resonates with the natural impedance of the power transfor-
mer, which is determined by the transformer's output voltage divided
by its rated amperage. Capacitive resonanace with the transfor-
mer's output voltage is not a good thing, as the res. voltage can rise
to several times what the transformer's output voltage is, which can 
destroy the transformer and/or the capacitor. This is the rea-
son most NST powered coils are built with LTR caps nowadays.
The larger than resonant cap limits the voltage gain in the primary
circuit and this tends to give the most "spark for the bang" with NST 
systems, especially with a synchronous rotary spark gap
(SRSG).

Many pig coilers opt for an STR primary cap and fire it with a
higher break rate through an asynchronous rotary spark gap (ARSG)
This is mainly due to the fact that an LTR cap would have to have an 
impractiaclly large capacitance/voltage rating combina-
tion ($$$$) to be viable for a high powered system. However,
a few pig coilers have ventured into LTR caps with synchronous
rotary spark gaps and have reported similar outputs as with
an STR cap with an ARSG.

Hope this helps.

David Rieben


----- Original Message ----- From: "Tesla list" <tesla@xxxxxxxxxx>
To: <tesla@xxxxxxxxxx>
Sent: Thursday, March 16, 2006 5:44 AM
Subject: LTR, STR ?


> Original poster: "R. Amaya" <dimon20042004@xxxxxxxxx>
> Hi all,
> Can someone please explain to me what STR and LTR means? Is there a 
> benefit to having one over the other?
> Any comments would be appreciated.
>  Robert