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Registered Member #902
Joined: Sun Jul 15 2007, 08:17PM
Location: North Texas
Posts: 1040
most of the ones for under $100 are mostly ferrite cored pulse transformers, not actual tesla coils and have a low pulse rate, but the solid state works off of a flyback and gets continuous sparks, I have the designs for all of them (except micro mite, which I have no clue about) if you have any questions about them... I would suggest building one though, and there is much information on this site, and the items of info. unlimited are a little but priced for what they are (being assembled by hand)... they are easy to build, but the pulse transformers in most of them come only through their company.
Registered Member #690
Joined: Tue May 08 2007, 03:47AM
Location: New Jersey, USA
Posts: 616
Anything you buy from that site can be built for way cheaper than they sell it for, but therein lies the problem: not everyone is up to a task like that. A spark gap tesla coil is not complex to build however, and if you want to make one of decent size for under $100, be prepared to do some scrounging.
Registered Member #187
Joined: Thu Feb 16 2006, 02:54PM
Location: Central Ohio
Posts: 140
Also, there have been many cautions posted here about that site, some of them pretty hefty. My personal experiences with them have ALL been negative. Suffice it to say, don't expect any support from them if there is a problem with your purchase, or if it seems what you received does not match their "sensational" descriptions.
Banned on 3/17/2009. Registered Member #487
Joined: Sun Jul 09 2006, 01:22AM
Location:
Posts: 617
Yeah and also their documentation is HORRIBLE. I bought a kit once some 7 years ago and was unable to put it together because of their shitty instructions.
Registered Member #902
Joined: Sun Jul 15 2007, 08:17PM
Location: North Texas
Posts: 1040
I had a cap that failed replaced easily from them... twice, still don't know if it was bad or if it was me (likely me, and apparently the Mythbusters had no trouble getting support when they messed up building the kit [their anti-gravity special, and them putting it in means they did not read the description of the device which uses thrust]) all their other kits seem to be fine that I have gotten from them, as are the plans... but maybe some of the ones that I have not tried are, but I do admit... their descriptions could be a little better.
Registered Member #1225
Joined: Sat Jan 12 2008, 01:24AM
Location: Beaumont, Texas, USA
Posts: 2253
Well, if you would like to make a spark gap tesla coil, see my new thread: It is quite easy way to get 5 inch sparks, and even streamers. It took me maybe a day to make it(i already had the parts laying around) and it was quite reliable.
Registered Member #162
Joined: Mon Feb 13 2006, 10:25AM
Location: United Kingdom
Posts: 3140
I too think that a spark gap Tesla coil (SGTC) is best for starting. The problem is a suitable source of high voltage to charge the primary capacitor. The most common is to use a neon sign transformer (NST) You must be sure that it's the old-fashioned kind that's just a transformer, - no electronics. Quite spectacular results can be achieved with a NST. Cheaper and not quite so powerful ia an oil-burner ignition transformer (OBIT), again not the electronic types. Discharges of up to 1 ft. should be achievable. One or more Microwave oven transformer (MOT) can be used for quite high power .. BUT I strongly advise against the use of MOT until you have a lot of high voltage experience NST and OBIT are by themselves unlikely to cause a fatal electrocution (by design) A TC using NST or OBIT could be lethal - though still unlikely. Just one MOT could kill you ! They scare the cr@p out of me!
If you can't get an NST or OBIT then any source of high voltage that is capable of charging the primary capacitor to a voltage high enough to 'fire' a spark gap. I made a pretty impressive SGTC using a 7kV 200 uA dc high voltage generator from a laser printer. Spark length is approximately proportional to the charging voltage and the primary capacitance value Using an NST or OBIT there are a hundred or more discharges per second (typically) Using a low power high voltage supply will give similar length sparks, but maybe up to a couple of seconds between 'bangs'. OR you could make a small SGTC with relatively low primary capacitance (1000pF or even less) for many small sparks per second, fun and instructive but not so spectacular. Most folk go on to build bigger and better TCs but eventually it's just a power game, more power = bigger/fatter/longer/louder.....
Registered Member #952
Joined: Mon Aug 13 2007, 11:07AM
Location: Finland
Posts: 388
Or you could make a flyback driver or an ignition coil driver. Those are very popular amongs beginners and give you a good introduction to HV. NST of course is the quickest way.
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