[TCML] PFC Question (again)

[bartb]

Hi John,

Even a small 10kva pig is LTR at 0.3uF which is huge for most coils 
(primary inductance "and" power across the gap). Have you ever tried a 
.3uF cap in a coil in a garage? I think Kevin is running a couple pigs 
and a rotary (no doubt). This is nearing a 0.7uF cap size "if LTR" which 
is huge! It's possible that a few like Kevin "might" be running LTR, but 
I think for the majority of pig or PT users (the garage coiler), the cap 
size is either resonant or STR from a standpoint of cost and energy.

My comment is aimed toward the "majority" of pig and pt users. It is an 
assumption on my part, but it's not hard to look at economy or even 
energy at the gap to dictate the need. I don't have recent data to 
support it, but past data does. In this area, I doubt much has changed. 
The economy really sucks the last few years and I doubt much change has 
taken place to allow large capacitances or the cost of the gaps needed 
(or the AC supply current to allow this). Probably a few out there, but 
I really doubt it is the norm.

Take care,
Bart

FutureT at aol.com wrote:
> Bart, Deano,
>  
> PT powered systems run very nicely at 120 bps with resonant or  slightly
> LTR cap values.  They  give an excellent power factor.  I think Kevin
> Eldredge's Biggg Coil is  running resonant or LTR also, using dual pig power 
> and giving 24 foot sparks at 120 bps  sync.  No PFC is needed for such
> systems.  Usually running somewhat LTR gives smoother  running than 
> resonant as explained in Morecroft's book of 1924, "Principles of Radio  
> Communications", (yes, LTR concepts are not new).  
>  
> Cheers,
> John