RE: flyback circuits for plasma globe

To: tesla-at-poodle.pupman-dot-com
Subject: RE: flyback circuits for plasma globe
From: Tesla List <tesla-at-stic-dot-net>
Date: Thu, 24 Apr 1997 18:19:04 -0500
Approved: tesla-at-stic-dot-net

Subject:   RE: flyback circuits for plasma globe
  Date:   Thu, 24 Apr 97 05:29:48 UT
  From:   "William Noble" <William_B_Noble-at-msn-dot-com>
    To:   "Tesla List" <tesla-at-pupman-dot-com>

Why don't you make it easy on yourself and for the first experiments
just get 
an old B&W tv set or an old computer monitor or terminal and pull the HV
lead 
off the CRT??  you will have a nice (but not sinusoidal) AC waveform
with lots 
of harmonic content for virtually no cost.  I have an old terminal I've
been 
trying to sell for $5 - I'm sure that TVs with broken CRTs and monitors
with 
broken CRTs cost even less.  A pair of 3055s (or virtually any other
high 
current transistor) can drive a flyback, and you can either let them
self 
oscillate, or you can drive them with a 555 and have some control over
the 
frequency and duty cycle.  The typical 3055 circuit which uses two low
side 
switches on a center tapped Xformer will generate a harmonic rich mostly 
square wave - I have used this circuit on electronic ignitions for cars
quite 
a bit - mostly using 400HZ aircraft transformers to bring the 6VDC car
supply 
up to 450VDC to charge the energy storage cap.  Works fine.

[Bill]  snip  
Ok, you've convinced me.
If I use those circuits that use a flyback for the HV, would they
work, I've seen the design with 2 2n3055 transistors that drive
the flyback, this design has been posted somewhere on the list before.
This circuit could give the HV I need , but what about the waveform,
this would give AC but in pulses, not sine wave.
----------------------------
Kenneth Aaron 
E-mail : kennetha-at-geocities-dot-com
http://www.geocities-dot-com/SunsetStrip/8736/
----------------------------