Re: 1st experiments with new coil

Subject:        Re: 1st experiments with new coil
       Date:    Tue, 22 Apr 1997 06:31:33 -0700
       From:    Bert Hickman <bert.hickman-at-aquila-dot-com>
Organization:   Stoneridge Engineering
         To:    Tesla List <tesla-at-pupman-dot-com>

Tesla List wrote:
> Subject:   1st experiments with new coil
>   Date:    Mon, 21 Apr 97 06:58:51 UT
>   From:   "William Noble" <William_B_Noble-at-msn-dot-com>
>     To:   "Tesla List" <tesla-at-poodle.pupman-dot-com>
> I decided to see how well the new coil pieces I had made worked.  Here
> is the
> coil description

> I hooked it all up in the normal manner, with the primary grounded to a
> piece                                             ^^^^^^^     
> of electrical counduit that runs underground for 40 feet, used all gap
> segments.  Tried the following configurations:

Congratulations on "first light" William! I assume you meant you
grounded the base of the secondary and not the priimary! The TC Primary
should always be "floating" except for the neon secondary center-tap. A
grounded strike ring above the primary is OK. 

> 1. no capacitor on top of the secondary, just the piece of wire sticking
> up -
> best performance at turn 7, next best at 13.  top turns of secondary
> glowed,
> got about 1/2 to 3/4 inch brush discharge from end of wire, with many
> small
> discharges from the piece of wire sticking up.  With the bottom of the
> secondary about 4 inches above the primary I got no discharge, with the
> bottom
> of the primary just below the secondary I got the small brush described
> above.
>  All other tests were run with the bottom of the primary just below the
> secondary - there was never arcover between primary and secondary.
> 2. plastic toilet float wrapped in foil on top of secondary - best
> performance
> at turn 8, got 3 to 4 inch "lightning bolt" type blue discharges from
> the
> threaded end of the float (where the foil was quite rough), could draw a
> 4 to
> 5 inch arc to a grounded wire (didn't measure this carefully)
> 3. made a torroid from 4 inch aluminum dryer ducting - didn't quite have
> enough to close the torroid but decided to try it anyway.  No free air
> discharge - best arc drawn from turn 6.

This doesn't sound quite right. Adding the toroid should have resulted
in the secondary frequency going down, and the primary tune
correspondingly should have required ADDING to the number of turns (as
happenned in case 2 above). 

> all of the above runs were short runs (15 sec to a minute) because the
> gap
> would heat up and the sparks would get shorter if I ran very long.
> Now, I know that I need more primary capacitance - that will come when I
> have
> time, and the gap got way too hot, so I'll need to redo it with larger
> copper
> pipe and then finish up with some kind of air mover to get a decent
> quench,
> and I'll need a real torroid some time.  So, the question to you-all is,
> is
> the performance of this partially done coil consistant with what you
> would
> expect????  

Basically - since the gap is poorly quenching, you're not seeing the
true potential of the system. Also, the system was definately not in
tune when you used the partial toroid. Finally, using a larger tank cap
will also boost your output performance by increasing your "bang" size.

I'm actually pretty happy that it did anything at all - This
> is a
> 10,000% improvement over my previous efforts (all thanks to reading this
> list
> for a few months).  My inclination is to play with some oil capacitors
> (7.5 kv
> units) that I have a pile of and see what happens, then when that is not
> satisfactory break down and make some like everyone else does.

If these are the older sealed mylar types... DON'T!! These have a very
nasty tendency to overheat and have been known to explosively self
destruct with little or no warning, showering anyone in the area with
metal debris, hot oil, and capacitor guts! These are like little bombs
in Tesla Coil use! Use them for DC filter caps or power factor
correction only. Go the LDPE route for performance (and safety)!

> Comments????
> (and, thanks for the help to date - this is much cooler than total
> failure)

Safe coilin' to you, William!

-- Bert --