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dc-dc voltage step up HUGE!!!
- Thread starter Lascannon
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Rectify a car inverter, maybe. Should work okay provided you have an adequate power resistor.
ALSO... Something you should always mention in projects like these: why?
ALSO... Something you should always mention in projects like these: why?
Thanks for the instant reply cypar! I have considered that method, the only problem is that this method isnt quite as... ok this sound silly but its kind of clunky, so to speak. I have a wierd aversion to strings of inverters, rectifiers, and converters. Does anyone else have any ideas? Would it be possible to modify this so that is doesnt invert?
And as for why, I am building a hand held mass accelerator. According to Lenze law, a flat coil pulsed to induce a current in a disk of aluminum will creat opposing fields and launch the aluminum disk at high speeds.
Thanks,
Liam.
And as for why, I am building a hand held mass accelerator. According to Lenze law, a flat coil pulsed to induce a current in a disk of aluminum will creat opposing fields and launch the aluminum disk at high speeds.
Thanks,
Liam.
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Okay, in that case, Google "coil gun"
Been there. thanks for pointing me in the direction of the car inverter! It turns out that some types invert after steping the voltage up. All I have to do it to pop the cover off and get my leads in before it inverts. With extreme care, of course.
Thanks!
Liam.
Thanks!
Liam.
vk2fro
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I dont get it - why not rectify the output, use it to charge a capacitor and dump the energy of said capacitor into your pancake coil?
the only way to step 12V up to 200 ish volts is either with a cockroft walton multiplier or some kind of oscillator feeding a transformer which then gets recitified. The former does so at fairly low currents, so would take ages to produce any useable power. The latter doesnt, and should produce a useable amount of power in a short time.
my cap bank works on the same principle - its basically an inverter or charge pump that converts DC into AC, then uses a TV transformer core to step that up to 900 volts AC, which then charges the 12,000uf capacitor bank via a (fairly high current) set of HV recitification diodes. A sensor circuit shuts off the charger at 880v to prevent overcharging.
Your hand held mass launcher might be served well by the guts of a disposable camera, and a few additional camera capacitors.
the only way to step 12V up to 200 ish volts is either with a cockroft walton multiplier or some kind of oscillator feeding a transformer which then gets recitified. The former does so at fairly low currents, so would take ages to produce any useable power. The latter doesnt, and should produce a useable amount of power in a short time.
my cap bank works on the same principle - its basically an inverter or charge pump that converts DC into AC, then uses a TV transformer core to step that up to 900 volts AC, which then charges the 12,000uf capacitor bank via a (fairly high current) set of HV recitification diodes. A sensor circuit shuts off the charger at 880v to prevent overcharging.
Your hand held mass launcher might be served well by the guts of a disposable camera, and a few additional camera capacitors.
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I have no clue what you need this for or why 12volts in..
You can get high voltage circuits that charge the Flash
Cap in cheap throw away cameras... as stated above...
Jerry
You can get high voltage circuits that charge the Flash
Cap in cheap throw away cameras... as stated above...
Jerry
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LaZeRz
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You can also make tasers out of those circuits :shhh:
vk2fro
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More of a shocker if you use those circuits - no where near the voltage of say the average 50,000 volt tazer. Unloaded (no caps) the camera's output roughtly 600-700 volts, and for a short period before they fry themselves (transistor not up to the job).
If you shock someone with a "camera" tazer all your going to do is piss them off.
If you shock someone with a "camera" tazer all your going to do is piss them off.
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Ok, getting away from the tazer ideas... laserbee that is exactly my plan. The reason I need this? I dont. Sometimes I do things just for the satisfaction it grants me. Thats what we young folks do these days. I though this would be cool.
Anyway, I have a capacitor bank made from 8x 200v 1000uf capacitors that my grandfather had sitting around from some project or other of his. I also have 2 gell cell 12v batteries left over from an electric bicycle of my brothers (he upgraded to larger cells recently). So, with these to work with...
The whole point of this project is as follows:
A portable mass accelerator based on an elecromagnetic field.
Why do I want one? I dont realy. I just love building things, and I though maybe you guys would want to put your two copper tokens in.
Thanks,
Liam.
Also, can anyone recomend a non-magnetic projectile to use?
Anyway, I have a capacitor bank made from 8x 200v 1000uf capacitors that my grandfather had sitting around from some project or other of his. I also have 2 gell cell 12v batteries left over from an electric bicycle of my brothers (he upgraded to larger cells recently). So, with these to work with...
The whole point of this project is as follows:
A portable mass accelerator based on an elecromagnetic field.
Why do I want one? I dont realy. I just love building things, and I though maybe you guys would want to put your two copper tokens in.
Thanks,
Liam.
Also, can anyone recomend a non-magnetic projectile to use?
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Aluminum ball bearing
Link for some small ones: http://www.smallparts.com/small-par...B003F24JGG/ref=sr_1_13?sr=1-13&qid=1317002121
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Can you recomend a source for aluminum ball bearings 
?
Does anyone know the internal resistence of capacitors? I just need to know if it is more than or equal to 1 Ohm.
Laserbee: I was unable to find an AC to DC inverter that did not reduce the voltage ot 12v. Can you recomend anything?
Thanks guys,
Liam.
?Does anyone know the internal resistence of capacitors? I just need to know if it is more than or equal to 1 Ohm.
Laserbee: I was unable to find an AC to DC inverter that did not reduce the voltage ot 12v. Can you recomend anything?
Thanks guys,
Liam.
vk2fro
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Your bank stores about the same energy as a portable defibillator - I'd be very wary around the terminals and install a bleeder resistor
ESR in a cap varies - if they're photo caps, they will have a fairly low ESR. its usually measured in milliohms, and can be measured with a $30 gadget off ebay - ESR tester.
Would this circuit suit your needs? keeping in mind that a good part of it can be removed to reduce components and board size?
http://uzzors2k.4hv.org/index.php?page=capcharger2
ESR in a cap varies - if they're photo caps, they will have a fairly low ESR. its usually measured in milliohms, and can be measured with a $30 gadget off ebay - ESR tester.
Would this circuit suit your needs? keeping in mind that a good part of it can be removed to reduce components and board size?
http://uzzors2k.4hv.org/index.php?page=capcharger2
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vk2fro
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A bleeder resistor is placed across the terminals of a capacitor bank to drain the charge away over a period of time.
The resistor needs to be suitably rated to the task. In your bank, a 25-30K 5 or 10 watt resistor will do. Mine uses a 10K 200 watt resistor as I want to get the charge down as quickly as possible in the event of an abort situation (my bank is absolutley deadly and wont give you a second chance if you become the discharge target
)
oh, and the platters out of hard drives work well as projectiles - they are usually made of aluminium with a ferromagnetic coating to store the data on (wont affect your project) and go sky high on a big cap bank
The resistor needs to be suitably rated to the task. In your bank, a 25-30K 5 or 10 watt resistor will do. Mine uses a 10K 200 watt resistor as I want to get the charge down as quickly as possible in the event of an abort situation (my bank is absolutley deadly and wont give you a second chance if you become the discharge target
)oh, and the platters out of hard drives work well as projectiles - they are usually made of aluminium with a ferromagnetic coating to store the data on (wont affect your project) and go sky high on a big cap bank
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You are so totaly my guy for this project! Any ideas on how to get my 110vac back to dc?
And, this is just an idea, feel free to shoot it down, but if I were to plase another object against my Al disk, could I re-use the same disk and fire a less-expensive, more aerodynamic projectile? The disk I am planning on using right now (until I get a better one) is one of 10 led heatsink/mounting boards. Aproxomately an inch in diameter, solid aluminum. Will this work?
Thanks,
Liam.
And, this is just an idea, feel free to shoot it down, but if I were to plase another object against my Al disk, could I re-use the same disk and fire a less-expensive, more aerodynamic projectile? The disk I am planning on using right now (until I get a better one) is one of 10 led heatsink/mounting boards. Aproxomately an inch in diameter, solid aluminum. Will this work?
Thanks,
Liam.