Original poster: "Dr. Resonance" <resonance@xxxxxxxxxx>It should be noted that Terry's sample calculation is for a 4 inch OD (outside dia.) tube. If you are using standard PVC schedule 40 water pipe (like Home Depot stuff) then the calculation would be for 4.5 inch OD tubing with 1,000 turns and becomes:
sec wire length = (3.14159 x 4.5 x 1000 turns)/12 in/ft. = 1,178 feet of wire.
If you are using 24 AWG double-build 200 degree C. magnet wire then the 1,000 turns would work out to a lineal winding length of 22.5 inches. Allow 3/4 inch on top and 3/4 inch on bottom of your tube so tube length (total) before winding is 24 inches.
A .0188 uF 32 kV MMC cap design (16 pcs of 0.15 uF 2 kV MMC caps in series) with a copper tube spark gap (200 CFM fan on each end --- one pushing and one pulling air through a 6 inch dia. pvc tube) will produce 58 inch long sparks with a 12/60 NST. Very compact and good performance for a small portable coil. Be sure to use a strike rail around the primary coil.
Dr. Resonance ----- Original Message ----- From: "Tesla list" <tesla@xxxxxxxxxx> To: <tesla@xxxxxxxxxx> Sent: Sunday, June 11, 2006 12:55 PM Subject: Re: wire lengnth
Original poster: Vardan <vardan01@xxxxxxxxxxxxxxxxxxxxxxx> Hi,Today, the "length of the wire" has been found not to matter as far as streamer length or anything. There are a few who still think it is based on 1/4 wavelength or something, but I totally disagree with them as do most.You want a coil say 4 inches in diameter and maybe two plus feet long. About 900-1200 turns works fine.The length of the wire is: 3.14159 x secondary diameter x number of turnsSo a 4 inch secondary with 1000 turns uses 1050 feet of wire. Much wire data is here in the back:http://hot-streamer.com/temp/FormulasForTeslaCoils.pdf Also see John's notes here: http://hometown.aol.com/futuret/page5.html Cheers, Terry At 11:31 AM 6/11/2006, you wrote:How do you calculate the length of wire I use to make my secondary coil?What's the formula?Thanks gang