Will this schematic work?

[wmmullaney]

Thanks for any help.

 

[ronsimpson]

It won't work for me because it is too small to see!

 

[whiz115]

nanotechnology?

 

[wmmullaney]

Haha, sorry

Just go here:

http://www.cappels.org/dproj/simplest_LED_flasher/Simplest_LED_Flasher_Circuit.html

 

[whiz115]

Wow...

this simple thing i think it is called "circuit with open base transistor"
yeah i think you can trust this guy that it works...

first time i see such implimentation...

 

[wmmullaney]

Thanks, will do.

 

[whiz115]

no...we thank you for this useful link!
although simple circuit it hides interesting theory!

 

[Nigel Goodwin]

no...we thank you for this useful link!
although simple circuit it hides interesting theory!

It's an EXTREMELY old technique - try googling for "neon relaxation oscillator".

 

[wmmullaney]

Your welcome, Whiz115!

 

[whiz115]

wmmullaney not all transistors (even 2n2222) can work on that circuit...
have you managed to find any suitable?

 

[Edd]

So does this operate on the same principle as the joule thief (ableit a much slower flash rate)?

 

[Speakerguy]

No, totally different... Joule thief uses a transformer whose coils constantly fight each other making the ckt oscillate, this uses the property of negative resistance that transistors can have.

 

[Nigel Goodwin]

So does this operate on the same principle as the joule thief (ableit a much slower flash rate)?

Red my post above and use google!.

 

[Edd]

Thanks speakerguy79.
EDIT: Thanks again, it all makes sense now.

 

[Speakerguy]

The behavior of breakdown in a neon lamp is an example of negative resistance, which is how the transistor is behaving in this ckt.

 

[wmmullaney]

Thanks, I havn't built it yet, I need the capacitor. Will a PNP transistor work here?

 

[Roff]

We discussed this circuit once before in this thread.

 

[wmmullaney]

No, Roff, this is NOT the same circuit, mine is open-base.

Thanks anyway.

 

[JimB]

All together now...

Yes wmmullaney, it IS the same circuit!

Try scrolling down a couple of posts and look at what Hero999 has posted.

JimB

 

[wmmullaney]

OK, well mine seemes to operate on a differant principle.