Re: first tesla coil
Don't feel bad Chester --- you're just making the same mistake most novice
coil builders do: they put on a fixed primary with a limited number of
turns and can't find the resonat point. The reason, in many cases, is the
resonant point may lie just outside the number of turns they have on their
primary. If this resonat tap point lies outside the number of turns you
have on the primary you can spend months of tinkering and trying to find a
resonat point --- and you won't. As you have discovered your coil
performance will be anemic.
Remove your copper tubing primary. Slit eight small pieces of cardboard on
edge (to form a temporary primary holder) and wind a 24 turn primary using
ordinary 12 AWG house wiring. Scrape a small tap on each turn but stagger
the tap location 1 inch as each turn comes around. Now you have a 24 turn
primary and you can find your correct resonance point on the primary. After
you tune it this way, then discard the 12 AWG wire and insert the proper
number of turns using copper tubing.
This should solve your problem. Happy coiling.
From: Tesla List <tesla-at-pupman-dot-com>
To: tesla-at-pupman-dot-com <tesla-at-pupman-dot-com>
Date: Thursday, September 23, 1999 5:11 AM
Subject: first tesla coil
>Original Poster: Katie Lowrey <lowrey-at-interpac-dot-net>
>Hi this is Chester Lowrey I just built my first tesla coil and here are the
>powersupply: 12kv 30ma NST
>cap: 2x 5" by 5" plate cap with 60 insulating layers each ten sheets of
>MIL polyethylene immersed in mineral oil. uf ??
>sparkgap: 8 coper pipe gaps
>primary: 7 turns 1/4 copper pipe 18" diameter flat pancake
>secondary: 6" by 24" PVC pipe wound with 24gau copper wire
>all conections made with 10gau insulated wire.
>from this description what do you think about it's performance? all i can
>currently get is 5 inch sparks at the most. my thoughts are that the
>transformer isn't big enough.
>but would it work better if i use a smaller primary and secondary?
>transformers are preatty hard to obtain when you live in hawaii and are
>15yrs. i just built the cap this weekend and was expecting better results
>than with my 7 bottles but spark gained 1' at the most
> well i would greatly apreaciate any help/comments PS. sowrey about
>the spelling hope you dont mind