Re: Switch-mode supply for bug zapper (fwd)

[<sroys@xxxxxxxxxxxxxxxxx>]

---------- Forwarded message ----------
Date: Thu, 23 Sep 2004 07:50:43 +0930
From: Matthew Smith <matt@xxxxxxxxxx>
To: High Voltage list <hvlist@xxxxxxxxxx>
Subject: Re: Switch-mode supply for bug zapper (fwd)

Gomez Addams wrote:
<blockquote>
You could probably just drive an old flyback transformer with a simple
transistor
circuit (circuits abound on the web for this) and skip winding your own
transformer.

You can also use the rectifier from a TV set for the output.  Half
wave, but who
cares about efficiency for this thing?  the power required is pretty
small.
</blockquote>

I had thought along those lines, but what I'm looking at is an offline device - 
the circuit being fed by 330V DC.  (240V, bridge rectified.)

TV stuff, if I recall, works with a B+ of 100V or so.  If I thought that the 
insulation on TV flybacks could take a 330V input, I wouldn't be wasting them on 
cookin' flies...

I suppose I could increase the number of primary turns.  Most of my flybacks 
were made by Thomson for - I believe - radar applications, and have exposed 
primaries ready for hacking.

-- 
Matthew Smith
Kadina Business Consultancy
South Australia