Re: newbie questions

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

Original poster: "harry by way of Terry Fritz <teslalist-at-qwest-dot-net>" <harry-at-prcn-dot-org>


----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: July 22, 2003 10:05 PM
Subject: Re: newbie questions


 > Original poster: "Crow Leader by way of Terry Fritz <teslalist-at-qwest-dot-net>"
<tesla-at-lists.symmetric-dot-net>
 >
 > ----- Original Message -----
 > From: "Tesla list" <tesla-at-pupman-dot-com>
 > To: <tesla-at-pupman-dot-com>
 > Sent: Tuesday, July 22, 2003 11:45 PM
 > Subject: newbie questions
 >
 >
 >  > Original poster: "harry by way of Terry Fritz <teslalist-at-qwest-dot-net>"
 > <harry-at-prcn-dot-org>
 >  >
 >  > Hi
 >  >
 >  > My name is Lance Williams , I am 36 yrs. old and I live in British
 > Columbia
 >  > Canada , I have a basic understanding of electricity and electronics,I
 > have
 >  > been lurking on the list since Xmas, in that time i have built a coil
with
 >  > the following specs:
 >  >
 >  > -3" dryer duct toroid 16" dia. oa.  a bit small but the kids prefer it
 > over
 >  > the 4"(lots more sparks :)
 >  > -14 turns 1/4" copper tube primary spaced 3/8" apart 45deg. inverted
 >  > conical 8" id. 19" od.
 >  > -4.25" pvc secondary form 30" long with 25" winding of 24Ga magnet
wire.
 >  > -powered with 2  12/30 nst's (soon to be 4 :)
 >  > -static gap 1"copper tube 6" long 11pcs. for 10 gaps at .02" each and 2
 > MOV
 >  > fans for quenching.
 >  > -2 homemade rolled poly caps .022 uf ea. in series  and an ESR of 19
and
 > 18.
 >  > -#4Ga welding cable for a ground wire to a 10' copper clad ground rod.
 >  >
 >  > With this setup i am achieving 26" continuous spark w/o breakout point
and
 >  > 32" w/ breakout points.
 >  >
 >  >
 >  > Now for the questions:
 >  >
 >  > -Can the ESR of the caps be lowered by wrapping it tighter and would
 > there
 >  > be any improvement in performance of the coil ?
 >
 > Welcome to the joy of coiling. You mention your caps have an ESR of 19 and
 > 18. What units are these, and how did you measure it? If by wrapping the
 > caps tighter, you compress the dielectric and get a shorter distance
between
 > the electrodes, you will increase the capacitance. I can't guess how this
 > will affect the ESR in your case though. Do your caps warm up at all (or
 > just the leads to them, or internal connections)?
 >
 >
 > KEN
 >

Hello Ken

The caps were measured by a friend of mine who has a TV repair business I
did not see what scale the meter was on when he measured them, the first
attempt had an ESR of 25 and 30 but I had used zap straps to hold them
together  and they failed shortly after being emersed in Xfr oil apparently
the oil causes the poly to swell and it blew out the zap straps the ESR went
to 145 and 190 respectively I then re-rolled them and used rings I cut from
pvc drain pipe to hold them together.The caps show no evidence of warming in
anyway in fact I have run the coil almost steady for over 30 mins. with no
warming of any components. When I finish the next coil I will tidy this one
up and see if one of the local schools would be interested in it.