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Electronics => Projects, Designs, and Technical Stuff => Topic started by: atferrari on October 15, 2014, 03:34:06 pm

Title: Negative ions generator
Post by: atferrari on October 15, 2014, 03:34:06 pm
Negative ions generator

Asuming the circuit is correct, I cannot grasp how it works.

Could anyone explain it?

Thanks for any help.
Title: Re: Negative ions generator
Post by: T3sl4co1l on October 15, 2014, 03:50:49 pm
What about it?

What's circled, did you mean to comment on that?

Frequency is awfully slow, but maybe it's an iron core power transformer.  36 diodes seems optimistic (36kV from a power transformer, yeah sure), but it should do something.

Looks like Gernsback, maybe Electronics Now / Poptronics, back when that was a thing.  Don't know what issue.

Tim
Title: Re: Negative ions generator
Post by: atferrari on October 15, 2014, 05:11:29 pm
What about it?

What's circled, did you mean to comment on that?

Frequency is awfully slow, but maybe it's an iron core power transformer.  36 diodes seems optimistic (36kV from a power transformer, yeah sure), but it should do something.

Looks like Gernsback, maybe Electronics Now / Poptronics, back when that was a thing.  Don't know what issue.

Tim

I expected the circled terminal of the secondary to be returned to ground. But not sure how it works as it is, I asked for an explanation.
Title: Re: Negative ions generator
Post by: Andy Watson on October 15, 2014, 05:20:34 pm
The text says "automobile ignition coil".  The low voltage winding will be energised for a period determined by the 555. When it turns off, the energy in the coil/transformer will generate a high-voltage pulse on the output 10-15kV. In comparison, standing the transformer on the +12V, or 0V (ground) makes little difference.  The reason for standing it on the 12V line is that standard ignition coils are made that way - i.e. only three terminals - one of which is common to both the low and high voltage windings.
Title: Re: Negative ions generator
Post by: atferrari on October 15, 2014, 07:55:20 pm
The reason for standing it on the 12V line is that standard ignition coils are made that way - i.e. only three terminals - one of which is common to both the low and high voltage windings.

Aha. Now I understand. Gracias for that.  :-+
Title: Re: Negative ions generator
Post by: IanB on October 15, 2014, 08:06:41 pm
There normally would be a high value current limiting resistor between the high voltage generator and the output needle. Otherwise if you touch the output you are going to get a nasty belt.
Title: Re: Negative ions generator
Post by: Alex_arg on October 19, 2014, 09:44:31 pm
Hi ! did you build it ??
I built one Negative Ion generator a few years ago, (oscillator, ferrite transformer and a Cockcroft-walton voltage multiplier), it works, but
High Voltage diodes get too hot  , then i replace the osc and trafo by a small 7"CCFL inverter and its working since then.
I can't measure how much cleaner the air is, but it's very effective killing  the flux and tobacco smoke :-+ . ( :palm: forgive me Father i smoke)
I think using a car ignition coil for that purpose is at least exaggerated, and maybe dangerous, as other user says, it would be adviceable to
put a 1Meg resistor in series with the needle(s).

Alejandro.
 
Title: Re: Negative ions generator
Post by: atferrari on October 19, 2014, 09:53:07 pm
Hi ! did you build it ??
I built one Negative Ion generator a few years ago, (oscillator, ferrite transformer and a Cockcroft-walton voltage multiplier), it works, but
High Voltage diodes get too hot  , then i replace the osc and trafo by a small 7"CCFL inverter and its working since then.
I can't measure how much cleaner the air is, but it's very effective killing  the flux and tobacco smoke :-+ . ( :palm: forgive me Father i smoke)
I think using a car ignition coil for that purpose is at least exaggerated, and maybe dangerous, as other user says, it would be adviceable to
put a 1Meg resistor in series with the needle(s).

Alejandro.

Not yet.  Maybe in the next weeks I will find time. Espero... :P
Title: Re: Negative ions generator
Post by: Alex_arg on October 19, 2014, 10:11:21 pm
Jaa Argentino ?? Si queres te envio el circuito x mail. Saludos