Re: Class D Tesla amp.

To: tesla-at-poodle.pupman-dot-com
Subject: Re: Class D Tesla amp.
From: Tesla List <tesla-at-stic-dot-net>
Date: Mon, 05 May 1997 01:29:01 -0500
Approved: tesla-at-stic-dot-net

Subject:   Re: Class D Tesla amp.
  Date:    04 May 97 19:56:08 EDT
  From:    Alan Sharp <100624.504-at-compuserve-dot-com>
    To:   "INTERNET:tesla-at-pupman-dot-com" <tesla-at-pupman-dot-com>

Greetings all,

Richard Smith wrote:
>then I have longed to build a solid state device that would achive
>compareable performance with out all the hassle of spark gaps designs. 

>So far in the archives I have not come across any thing that has to do
>with a good RF power amp for driving a Coil.  Has there been a thread? <

There is in the archive (misc section) a 500W + design by Rob Frost
which is probably what you are looking for. 

Also Duane Bylund's book "Modern Tesla Coil theory" has a 1000w
design based around npn power transistors. 

It can be done but it is not without hassle. You can get 12" sparks with
500W and the devices are very efficent. But you can't get the high peak
powers
of a spark gap coil.
These designs are built around PWM chips ie 3524, 3825 driving half
bridges into an output transformer, connected to the bottom of a
magnifier coil.

Others on the list have built Bylund's design or are working on their
own ideas.

I get 14" arcs from my (horrible) push pull design.

A 10kW monster has been built by Mark Barton which gave 3' discharges
while it lasted - it blew!

Its fun but its not easy.

Alan Sharp (UK)