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Simple 555 dc pulse generator.

I found a circuit in my electronics book for makeing a dc pulse generator based on an NE555. The circuit includes a pot for adjusting the frequency. I am going to use this simple generator for driving an ignition coil which power a Tesla coil. im wondering if I could build this circuit and then after the generator, before the coil, place a voltage divider where on of the resistors is a pot for adjusting the voltage, and then another pot in series with this output the make a square wave generator with adjustable voltage, frequency, and current.

Reply to
ngdbud
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Yes a pot. setup as a voltage divider will allow you to adjust the output voltage, however I think you will find you need more drive for your ignition coil. That means your 555 will end up driving the base of a power transistor or a FET. If you keep looking you will find a 555 circuit with independently adjustable on and off times, it has two diodes in the trigger/ discharge circuit. This will allow you to experiment for the best on time.

Mike K.

Reply to
amdxjunk

Thanks. I hadn't realy considered the power levels a 555 can handle, I had only thought about them breifly. I have a couple of 2N3055's already mouned on heatsinks I can use. Do you know how many watts a typical igniton coil can switch? I am hoping for an output of 5-10 kv at at least 1 ma.

Reply to
ngdbud

10 to 20 watts? Considering the inefficiencies, that should be good for 10 to 20kV, which won't make much of a spark! 
--
 Thanks,
    - Win
Reply to
Winfield Hill

My reference was to the available output power, under actual operating conditions (not DC). Also, it was a total WAG. :>) I don't believe it's a good starting point for a Tesla coil.

--
 Thanks,
    - Win
Reply to
Winfield Hill

Hi NG, I'm not not one to second guess Win, (except on politics ;-) However I found this site that suggests the coil will draw about 5 amps at 6 to 8 volts. The low voltage is described in the article. About 100 watts at 12 Volts.

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Mike K.

Reply to
amdxjunk

Win, I agree it's probably not the best starting point, however he is a 14 yr old newbie that is smart enough to get some experience on a 12 v pulsed system before he hooks onto a 12kv 30ma. continuous current system. Mike K.

Reply to
amdxjunk

Thank you, newbies about the nicest thing I've heard in this group ;)

Reply to
ngdbud

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