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Is it possible to build a simple electronic sparker similar to those found in grills? I want to have two wires that create a quick spark between them when a button is pressed.

I'd like it to run off of a AA or 9V battery.

Are these simple to build? I would think it is a capacitor / step-up transformer but I'm not sure. I guess I would somehow have to deal with converting DC to AC as well. I have a power supply for a scanner flourescent bulb. Could I possibly rig that to create a spark. It runs off of a 9V battery.

They are a piezo element that generates a high voltage through mechanical action. Pushing the button "thumps" the piezo. You can buy them as replacement parts at most hardware stores. I bought one at Home Depot. Look for "ignitors" in the BBQ grill department.

-JPKNHTP

I was looking through the internet, and found the following website:

http://www.geocities.com/CapeCanaveral/ ... 2/fbt1.htm

It talks about using simple circuitry and a flyback transformer to generate very large sparks between two wires.

I've got everything I need except the flyback. I know they come in monitors and I've got a broken monitor in my garage (it turns on but has a really dull picture, I asked about it in the computers section a while back) which I would tear apart. However, I don't know where the really high voltage stuff is in a monitor. Could anyone tell me what is still HV after a few weeks (maybe 3 or 4, not really sure) of being unplugged?

Otherwise, the website mentions briefly about winding your own coil, but they forgot to say how many turns on the secondary. How many is required for a flyback transformer?

I capacitor in the HV section will store a charge for several weeks. One safety tip when working on a monitor is to short a flat blade screwdriver shaft to ground and slip the edge of the blade under the rubber cup that surrounds the HV wire where it attaches to the tube. If the cap is charged you will hear a loud "pop" when HV shorts to ground. (read up on this before trying it).

If you want to find a flyback for cheap look for a junker TV set at a thrift store

Answers to many questions:

The electronic grill ignitors are available for purchase. They replace the button on the grill and run off a battery. Here is one that runs off a single AAA battery:

http://www.accentshopping.com/store/bbq ... /GGEIB.asp

Retail is much cheaper. I've seen these at "Wally World", Menards, Meijer, and a host of others including Home Depot. These are in the grill repair parts and are usually just a blister pack or bag on a pin. Why Home Depot won't sell you one is a mystery. Maybe you should have a talk with the district manager as to why something for sale in their store was not for sale to you. (In Illinois they cannot sell spray paint to kids. In fact they ID me and I'm in my late 30s!)

The windings issue is straight forward if you understand transformers. You must know about turns ratio. Voltage steps up or down by the turns ratio. For instance if you have a 10:1 turns ratio and put 120 volts AC on the "10" side you get 12 volts AC on the "1" side. In this case they state the PRIMARY is 10 turns Center Tapped. Your source is 12 volts. To get to 12,000 volts you need at least 1,000 turns on the secondary. I'd go 2,000 or as many as 4,000 turns.

To expand on Jimandy's high voltage comments:

Flat blade screw driver is correct. The longer the better. PLASTIC or Rubber handle. DO NOT use wooden handle. Connect a wire between the metal ring around the front of the CRT (usually you will see a ground wire connected to one of the mounting screws). This ground wire is where you want to connect the wire. Connect the other end of the wire to the screw driver shaft. A good way to do this is to use a clip lead.

Next, if you are right handed, put your left hand in your back pocket. Vise versa if you are left handed. (I'm not joking. Do this for real.) Slide the tip of the screw driver under the suction cup on the top of the CRT. I don't think I've ever seen anything but a red wire coming out of the suction cup. Listen for the POP. It might be a simple snap that you can barely hear. Other times it may make you jump. Whatever you do, don't take your hand out of the back pocket.

Use the tip of the screw driver to unhook the metal clip under the suction cup. This is a spring device with hooks and takes some work. Remember, the hand you are NOT using should still be in your back pocket. Once the suction cup is off, wait a minute or two and stick the screw driver back in the hole. You might have to repeat this several times. As far as how long with a CRT hold a charge? How about years. You are dealing with 25KV to 35KV DC on a color CRT.

Once you have discharged the CRT, follow the wire with the suction cup to where it begins. You will find it goes into a plastic box. This is the flyback transformer. It will have a number of solder connections on the bottom. Right next to it will be a large heat sink with a big transistor or multipin heatsinked IC. This is the HOT or Horizontal Output Transistor. I'd pull the heatsink, transistor, and flyback. If it is a multipin IC, you might not want to waste your time.

As far as working with the flyback, good luck. You can Ohm out the pins to find which ones are connected and find a suitable set of windings to use as your primary. I'd follow the ground wire I spoke of for the CRT back down to the main board of the monitor. Follow its connection back to the flyback. Note which pin this is as this is the GROUND of the flyback. If Edd is around, he might be able to enlighten you with information about the particular flyback, if you post its number.

"In fact they ID me and I'm in my late 30s!" Looking at the photo of yourself you used for an avator here I'm not surprised

The rest is good advice!

Mike, the one hand in pocket is really good advice.

Cheers,

-JPKNHTP

Thanks for all the replies.

First, I'm not questioning the advice, but out of curiosity, why does putting your opposite hand in your back pocket matter?

Second, JPKNHTP, I don't know if you got my last message, but would it be possible to work one of those flybacks into our trade? I don't know how much the ignition coils go for, but if they are cheap one of them as well? Let me know when you have a chance.

-JPKNHTP

Mike- I'm looking for a "sparker" also! It's an alternative to the piezo on a potato gun. Questions- What is the duty cycle of your application- i.e., how often do you need the spark, once every few seconds, once every few minutes? Also, do you have size limits on how big of a package you can have? Is your spark occuring in air, or some other atmosphere?

jwax, thats so funny!! I'm building the exact same thing!!! A friend of mine has one and it's got to be one of the most amazing things I've seen.

My friends potato gun has the old kind from a grill where you push and it sparks once it makes the click. It's fully mechanical, no electronic.

Here's what I'm thinking right now: Using an igntion coil, wheather i get one or wind my own (looks pretty simple), a spark plug, a momentary push button, and a 9V battery.

If I really wanted to get fancy I would build a 555 circuit to make it continuously spark, but i don't think I need that much.

I really need it to spark once, maybe twice or third if it doesn't ignite the first time. Then there's at least a minute or two before I shoot it again.

We use the ignitor from a coleman latern on our 'tater cannons down here.
They are the twist type that use a zippo lighter flint, just drill a 1/4" hole slip it in and put the nut on..
For fuel we use the cheapest hair spray we can find...

Just a bit of advice. From my understanding potato guns are illegal in most places throughout Illinois, where Mike and I live. Just like most fireworks and other fun things.

That being said please don't duct tape the thing together! Be sure you use primer and cement. Most plumbing applications are low pressure. The cement process cures in about half an hour to an hour. This is fine for plumbing a sink or similar application. Since potato guns put the joints under pressure let the joints cure overnight. If you are a reader of MAKE magazine you may have read an article they had about this interesting toy. The Maker that wrote the article used clear tubing to make his gun. It made a very interesting light show at night.

The next question is just out of curiosity: What do you use as fuel? One source of fuel is cheap generic hair spray (the name Aqua Net comes to mind). Another is starting fluild (nasty stuff). DO NOT use gasoline.

As JPKNHTP stated (and I should have explained) the one hand in your pocket will not allow current to flow across your heart and body core. I've not been nipped by a monitor flyback or CRT yet. I have by automotive and small engine ignitions and it can cause spasms, uncontrolled hand and arm contractions, and numbness. Banged knuckles and some of George Karlin's seven dirty words are the usual results.

So why the hand in the back pocket? The heart has what is called a SINUS RHYTHM when working properly. The heart muscles receive a pulse which causes the heat to contract in a particular order. Introducing a current which upsets this proper rhythm can damage the heart or cause it to go into an improper state where the heart does not contract as it should. I believe the term is called fibrillation; a condition where the muscles fire in a random fashion. Now lets take a situation where your right hand is discharging the CRT and your left hand is free to do as it pleases. Should your left hand decide to "help" in the situation and be on ground (which is very easy to do in a monitor or on a work bench) and your right hand makes contact with the CRT high voltage, the path is directly across your heart. By placing your left hand in your back pocket you "REMEMBER" to not let it grab anything else in the monitor or near by. This helps prevent current traveling past/through your heart.

You may think I jest but I do not. I put my left hand in my back pocket or through my belt. It may seem silly but I'd rather spend ten seconds looking silly rather than a lifetime regretting a stupid mistake. The back pocket thing is also a good idea when working on an energized chassis and taking live measurements inside a monitor or other high voltage application. But most of this goes out the window when working with high power RF, but that is a subject for another thread.

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.…Is it possible to build a simple electronic sparker similar to those found in grills? I want to have two wires that create a
quick spark between them when a button is pressed…..

If you were after the continual spray of sparks, this circuit is hard to outperform using a $1 salvage car ignition coil from a ‘tirty ate Hupmobile,etc; by using it as its driven spark source.



Realize…… that this may be more than you need…but it can be scaled downwards by merely scaling down the drive level as well as / or the supply voltage.
Here is the how-to-info:
http://home.golden.net/~kpwillia/drcirc.htm

If you merely need a single hot spark of any voltage level as created just above, its simply a matter of the initial charging up of a capacitor and then discharging it into that car ignition coil primary with a conventional momentary contact pushbutton switch to get yourself a single spark burst.

UPDATE:
This is the point where I had checked back to review some previous data and saw some additions had revealed the end function of the sparks requirement. Therefore, I had to go back and delete some info on impacted Piezo generation. In this case you might merely use the last paragraphs info where you experiment with a series string of multiple 9V batteries in charging up a cap when a SPDT switch is in the “offâ€