Re: IT Works! Quo Vademus from here?

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

Original poster: "Terry Fritz" <twftesla-at-uswest-dot-net>

Hi Matt,

You might want to try a larger top terminal or adding a second one above the
first.  In many cases like yours, a larger top terminal will add to spark
length. 

I don't know what wrong with the PFC cap thing.  The PFC cap should be directly
across the NST's AC terminals.

Cheers,

        Terry


At 10:23 PM 1/28/2001 -0500, you wrote: 

>
> Hi Terry & All, 
>
>       Grandson and I fired up the new & improved coil today. It produces 18" 
> streamers to a 1-inch brass ball suspended above it from a grounded #10 wire.
>
> We are not running to full power indoors, as this is a basement workshop with
>
> overhead gas line. There are a couple of things that I am unsure of about 
> where we go next to make improvements. (Part of this a repeat from prior 
> posting) 
> 1) Ed posted a note about 2 weeks ago in which it sounded like he was saying 
> that putting a PFC cap across an NST is not good for it, is counterproductive
>
> to current limiting, and may cause more trouble than it is worth. Perhaps 
> this explains what is happening with our coil. Without PFC, the voltage and 
> current rise smoothly from 0-60V and 0-8.2Amp respectively. At about 62 V 
> input, the main gap starts to fire and the ammeter needle (Weston model 155 
> in oak case) does a "random-walk" over the range of 6 to 14 Amp. With the PFC
>
> correction in the circuit, the voltage and current rise smoothly from 0-60V 
> and 0-5.95A. At about 62 V input, the ammeter needle again does the 
> random-walk over the range of 6 to 14 Amp. Does this indicate a problem with 
> the PFC, NST, or is it just me not understanding the way it operates? 
>
>       The system is configured as follows: 
>
> 1)    Power Box: Inlet cable, 15Amp fuse, inlet switch, 15Amp EMI filter 
> (backwards), 20Amp/120V Variac, 0-130V AC voltmeter, 0-25 Amp ammeter, power 
> outlet switch, outlet cable. Power box components grounded to mains ground. 
>
> 2)    PFC Box (Tupperware): 6 parallel 660VAC caps, 89.6uF total, outlet 
> cable. 
>
> 3)    "Blitzwerfer": 15/60 NST w/safety gap. Each output leg of tranny has a 
> 200-ohm, 200W wire-wound resistor at ~300 uHy (open porcelain tube 1.675" X 
> 6.5") as a poor-man's RF choke.- Aspirated spark gap (ala 
> www.Altair-dot-org/projects/suckergap/) hooked to shop-vac. A 0.01822uF x 60Kv 
> rolled cap, 12T, 0.25"Cu flat spiral primary wound 0.75" c-c, 23" above 
> floor, diam 6.375in to 24.375in Tapped -at-7.1T ( 17.10 uH) Secondary: 4.28" x 
> 820T 23ga starting 25" above floor for 21.16in  (13.96 mH.) Toroid: 4.25x18  
>
> ( 13.75 c-c)  -at- 52" above floor. Secondary is grounded via 40" #6 battery 
> cable to 5/8"x48" copper-clad rod driven 42" through basement floor as is 
> 30in diam. strike rail mounted at 25in above floor. No other HV component is 
> grounded. Loaded secondary resonates -at- 285 kHz. 
>
> We have run this thru ETesla6.11 and gotten the pictures of Voutput and 
> Soutput using Excel surface graph to make a contour plot.Claculated F is 277 
> kHz. Unfortunately, I haven't a clue as to what they indicate we should do 
> next, or where problems, if any, exist. I would be happy to forward these off
>
> list to anyone who can tell us what they indicate in terms of improvement. 
>
> Matt D. & Matt D. 
>
>