Re: Any suggestions for more spark length

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

Original poster: "Gerry Reynolds" <gerryreynolds-at-earthlink-dot-net> 

Hi Chris,


Where is Cp at with respect to the Cres of the supply??  For a static gap,
you might want to set Cp = 1.6 * Cres.  Also, do you have a fan for your
spark gap?

2 series MOTs and 2 series MOV???  How does the MOV voltage compare to the
peak voltage out of the MOTs???  Doubler??  Is this a DC coil?  I think Im
confused.


Gerry R.


 > Original poster: "Mudford, Chris" <chris.mudford-at-agresearch.co.nz>
 >
 >
 > Hi all
 >
 > I need some hints as to where my power is going?
 >
 > Coil specs are:
 >
 > Power supply:  2 series mot with doubler having 1.05 uF in each HV leg, 2
 > series MOV diodes with by pass caps between legs and 110 ohms in each
 > output leg.  There is a safety gap to ground (CT of two transformers) from
 > both HV outputs.
 >
 > Spark gap: 5 pipe linear satic gap (2 pipes on bottom, 3 on top, separate
 > the top further from bottom to adjust gaps)  Total gap ~4 mm.  Parallel to
 > supply.
 >
 > Capacitor: 10 seriesed WIMA FKP1 (0.068 uF, 1600 DC, 650 AC) with 7
 > parallel strings.  33 MOHM bleeder across each cap.  Connects to inner
turn
 > of primary and spark gap.
 >
 > Primary:  14 turns of 4.8 mm refrigeration tubing spaced at 4.8 mm as flat
 > spiral.  35 mm space between secondary and primary inner turn.
 >
 > Secondary:  90 mm diameter wound at 540 mm length for 6:1 ratio for 1630
 > turns (0.28 mm wire, 0.32 mm including enamel).  Bottom turn of secondary
 > ~30 mm above primary.Toroid ~90 mm above last turn of secondary (to centre
 > of minor toroid diameter).
 >
 > Toroid:  Spun aluminium 50 x 180.
 >          Silver tape toroid 80 x 600.
 >
 > RF ground:  Short length of steel into ground which I clip to
 >
 > With the small toroid it is producing ~14".  I quickly built the bigger
 > toroid hoping to get rid of the multiple streamers with the smaller
 > one.  But, was still getting 3-4 streamers into air at ~18".
 >
 > Things I think are poor.  SPARK GAP, TOROID, COUPLING, RF GROUND, POWER
 > FACTOR.
 >
 > With a supply like this how does one approach power factor.  The mains
 > supply lead is getting warm.
 >
 > Hope all you guru's can have a think about this and give me some ideas.
 >
 > Cheers, Chris (NZ).
 >
 >