Pulsejet construction

[Mark]

These are some I use when I can get away with it.
Mark

[Mark]

Hey, how about forking over $100.00 US dollars for this device? Ah, nothing like the love for your fellow man. And with 100% feedback, you can't go wrong. But for me, I would want a really hot spark for that much money, and not some static electricity equivalent. You might just as well buy some carpeting and scuff your feet.
Mark
http://cgi.aol.ebay.com/ws/eBayISAPI.dl ... eName=WDVW

[Mark]

For $100.00, you could have 100,000 volts.
Mark
http://cgi.aol.ebay.com/ws/eBayISAPI.dl ... otohosting

[Mark]

Or for $49.95 you can own 900,000 volts. Might be fun to accidently shock yourself too.
Mark
http://cgi.aol.ebay.com/ws/eBayISAPI.dl ... 26526&rd=1
http://cgi.aol.ebay.com/ws/eBayISAPI.dl ... 19100&rd=1

[Mark]

Interestingly, my 500,000 volt stun gun crackled loudly, yet it wouldn't light tissue paper, and the same for the whopper 100,000 volt unit with dial and polarity toggle switch. It crackles like heck too and makes a ~3 inch spark between those adjustable pointy brass rods. but nay, neither will light tissue paper! A buzz coil will and so will my tiny high voltage device that is from Emco. Both can be battery powered which is nice. I have a neon sign tranformer, it is too "hot" and would melt the spark plug electrode, it doesn't crackle as much as it buzzes with a furry glow surrounding the spark. It's too serious. Then I have a car coil/transistor unit. That will light paper too without that annoying overkill.
Mark

[larry cottrill]

Interestingly, my 500,000 volt stun gun crackled loudly, yet it wouldn't light tissue paper, and the same for the whopper 100,000 volt unit with dial and polarity toggle switch. It crackles like heck too and makes a ~3 inch spark between those adjustable pointy brass rods. but nay, neither will light tissue paper! A buzz coil will and so will my tiny high voltage device that is from Emco. Both can be battery powered which is nice. I have a neon sign tranformer, it is too "hot" and would melt the spark plug electrode, it doesn't crackle as much as it buzzes with a furry glow surrounding the spark. It's too serious. Then I have a car coil/transistor unit. That will light paper too without that annoying overkill.
Mark

Mark -

That is all a function of the available current, rather than voltage [which basically determines how big a gap it will jump].

Beware neon transformers - there is enough current handling capability there that they can be instantly lethal! That "fuzzy" high-temp arc is good for things like Jacob's ladders.

The Model T coil can light paper, fluff cotton, etc. and it can occasionally pick you up out of your chair via involuntary muscular contraction, but I've never heard of it killing somebody. It's relatively cheap and easy to get high voltage if you don't need much current.

L Cottrill

[Mark]

I run my buzz coil for long periods at a time and it just keeps going and going. I bought another one cased in black plastic just in case it gives out, but the wooden box one has lasted me years and years now. They sell them out of California from a Antique Ford company. I think they are meant to run on 1 or 2 amps at 6 volts, but I am using a small plug in power supply that was for a wall phone, it's rated 12 volts and 800 ma. I tried a lot of little transformers I had, most didn't have enough power to even drive it weakly, all will run my little EMCO device, the series E101 if you refer to the chart, it is said to deliver .2mA at 10,000 volts. I like to run my EMCO device on the lowest current and voltage because after a few minutes one side of the 3 ounce device gets hot if I drive it full power or use a tiny 9 volt battery for too long. But low power is still hot enough. You can see the EMCO device is meant to safely draw less than 300mA at 0-15 VDC. I have a bevy of tiny wall transformers that fit that bill and this keeps it from getting hot but still lights paper.
Has anyone measured what a buzz coil puts out drawing 1 or 2 amps and 6 volts?
Mark
http://www.emcohighvoltage.com/ Sorry you have to use the search and type in E101 and take the first hit to see the chart.

[pezman]

That EMCO thingy is pretty cool. Where did you buy it? The E101 might be ideal for a corona ignition and I'd like to get an F101 or F121 to test an idea that I was kicking around.

Thanks for the EMCO link!

[Mark]

Well, I got in touch with a representative from EMCO. I wanted to buy some of these but they only sell to corporations. I told Mrs. Crabtree I bought a new one on ebay and that I was just wondering how much they sell them for. She wouldn't even divulge a price.
I remember some fellow on the old forum recommended them, he ran his on a car BATTERY CHARGER. I think he blew his out eventually. That is way more than what they are suppose to run on amp wise. They are really cute devices though, occasionally you can see an equivalent device out of Belgium on eBay. And there are some other companies that make similar devices in the US.
If you wanted to make piezo or gas grill type sparks, maybe one of these ultra tiny devices would be neat for compactness.
http://www.emcohighvoltage.com/Qseries.PDF
Some copiers or other machines that use high voltage might have these things in them, perhaps you could salvage one from some discarded machinery. They hold a charge after you shut them off, I've learned not to touch the leads until I short them out. It's only a tingle but not pleasant.
Mark

[Mark]

Here's a tiny little device, I wonder if 7KV and .6mA would really kill you? I don't know too much about electricity, but it seems on the low side. I guess if you had a bad heart ... My smallish neon sign transformer's output is 5.5KV and 20mA.
What's negative DC, I know almost zip about zap.
Mark
http://cgi.aol.ebay.com/ws/eBayISAPI.dl ... otohosting

[Al Belli]

Hi Mark,

The high voltage output is negative polarity with respect to ground.

Al Belli

[Mike Everman]

I am very partial to the AC spark units from about any kitchen range. Readily available, and if your out on the range, so to speak, you can run them off a cheap inverter in your car. It always works. Barely hurts when you leave it on and grab it, which you will. ;-)

[Mark]

Well, those units were the cheapest spark I came across, I bought 3 for $3.00 each I think. Tic, tic, tic, they are a modicum stronger than the outdoor gas grill tickers and aslo stronger than the piezo clicker. Still, they look kind of unmanly, and as you say, it barely hurts if you touch it. I'm starting to feel like a Consumer Reports author on the subject. "Of the weak and thin spark class of ignitors, the indoor gas oven ticker scored highest."
Mark

[Mike Everman]

"Four out of five homemakers agree, when starting a jet engine, a balance of economy, spark hot-ness and hand zinging good times is desired in a sparker.."

[pezman]

I took the trnsformer out of my Walmart bug zapper ($15) and it works fine as an ignition coil. I can generate a nice spark with a 9v, 300ma transfomer and an even nicer one with a 30v transformer - so a 12 volt car battery or gel-cell should work fine in the field.

Basically, I'm trying to build something that generates "back-fires" on purpose, so I think that an active ignition will be part of the deal.