I'm sure this is a simple question, but I'm going to ask anyway.

I stared at this thing for 20 minutes last night and can't get my head around how it works.

How does the 3v dc get stepped up to the 300+v required for a strobe light? I know the transformer does the stepping, but how does that one transistor work and how does it allow the transformer to work?

 

hi Andy,
This is a valve version, but it explains the principle of a transformer 'blocking oscillator'.

http://www.vias.org/eltransformers/l...ers_11_01.html

__________________
Eric
"Good enough is Perfect"

PIC tutorials:
Gramo's: www.digital-diy.net/
Bill's: www.blueroomelectronics.com/

 

The power transistor is an oscillator. Part of the secondary winding of T1 applies positive feedback to the base of the transistor to keep it oscillating. Then the transformer steps up the AC voltage, the rectifier converts it to DC and the 470nF capacitor filters it.
When the voltage is high enough then the neon bulb conducts current which turns on the SCR that applies the high voltage to the trigger transformer T2 to create a few thousand volts to start the strrobe light.

__________________
Uncle $crooge

 

Thanks guys.

It helps knowing what its called I googled 'blocking oscillator' and found quite a bit on them. I just won a scope on ebay, should be here next week. I think that circuit is the first thing I will build to look at with it.