UK coilers ? + stuff (fwd)

---------- Forwarded message ----------
Date: Fri, 31 Jul 1998 18:37:50 +0100
From: "chris.swinson" <chris.swinson-at-zetnet.co.uk>
To: tesla-at-pupman-dot-com
Subject: UK coilers ? + stuff

Hi all,

I've just joined the list to help and swap ideas with more experienced

First of all are there any people in the UK ?  I live in Uttoxeter (
Staffordshire , Near Burton on Trent ).  Any one live near me ? 

I haven't built a large coil, mine is only a 240 watter.  I can get up to
9" sparks off my coil.  Has anyone built a 240 watt coil and got bigger
sparks than that ? 

My first question.... My secondarys resistance is about 77R, Does anyone
know how much resistance I can actually get away with.  I'm just builing a
200R coil just to see what happens. 

Has anyone tried a DC transistor driver, My high voltage input it a small
8Kv -at- 30ma, thats 240 watts.  If I used 160 volts at about 2A that would
give about the same wattage.  But would this work as well as the high
voltage ?  I know that the cap and spark gap would not be needed as the
transistors would have to switch to about 600Khz anyway.  As far as I can
tell this would work better and the coil should run a lot smoother, Any
thoughts any one ? ? 

I also don't 100% understand when people say build coils with a 3:1 ratio,
can anyone enlighten me ?  The ratio for my coil as I see it is 1:260 so
where do you all get 3:1 from ? 

Accroding to my secondary inductance calculations my coil is about 39 mH,
But actaul measurement shows 7.4mH. Does anyone know is this reduction in
inducatance is good ?  As far as I see it , it is but as far as I can see
it may increase capacitance which is bad.  Oh, I varnished my coil so
thats why it's different.  I was thinking of doing 2 coils the same, but
laqureing one to compair results, But can anyone tell me whats what before
I send the time doing more coils ? 

Whats the output current of a coil ?  I know the capacitor may well give a
very small peek of up to 1000's of amps, But the current rating of the
wire in my secondary is about 140 ma, Does this mean I can only draw 140ma
or is there something else to it all. 

Has anyone tried a magnet as a discharge terminal.  I used a old speaker
magnet ( donut ) and I get evenly spaced sparks off it, about every inch
around the magnet.  This is rather interestinf to me, Anyone tried this
know why it does that ? 

Has anyone got any thoughts on using a valve as a spark gap, I used a
small ECC88 ( I think) there was 2 plate inside which were close enough
for the spark to jump, note that I only used the valuve not heaters or
anything else at all.  My coil ran very well indeed.  It was a lot
smoother and the performance was a lot better.  But it got a tad hot ans
exploded so I decided that I ought to find out more about it if I can. 
Anyone help ? 

Thats it, Thanks to all who have stayed tuned :-))

All the beST,