[Prev][Next][Index][Thread]

Spark Gaps




----------
From:  Malcolm Watts [SMTP:MALCOLM-at-directorate.wnp.ac.nz]
Sent:  Wednesday, April 15, 1998 11:21 PM
To:  Tesla List
Subject:  Re: Spark Gaps

Hi John,

> From:  John H. Couture [SMTP:couturejh-at-worldnet.att-dot-net]
> Sent:  Wednesday, April 15, 1998 12:54 AM
> To:  Tesla List
> Subject:  Re: Spark Gaps
> 
> 
>  At 03:50 AM 4/13/98 -0500, you wrote:
> >
> >----------
> >From:  richard hull [SMTP:rhull-at-richmond.infi-dot-net]
> >Sent:  Sunday, April 12, 1998 5:05 AM
> >To:  Tesla List
> >Subject:  Re: Spark Gaps
> >
> >At 08:33 PM 4/11/98 -0500, you wrote:
> >>
> >>----------
> >>From:  Bert Hickman [SMTP:bert.hickman-at-aquila-dot-com]
> >>Sent:  Friday, April 10, 1998 10:25 PM
> >>To:  Tesla List
> >>Subject:  Re: Spark Gaps
> >
> >>Thratron or transistor switches were used by Richard Hull and Malcolm
> >>Watts respectively to switch off primary current at earlier current
> >>"zeros" (of the coil's fundamental operating frequency) during a number
> >>of very interesting quenching experiments last year. Malcolm's attempts
> >>to turn off a low-power transistor-switched primary circuit at points
> >>other than primary current zeros did result in the expected high voltage
> >>spikes stemming from rapid di/dt, but it's not clear that the an arc's
> >>characteristics will permit this to actually occur under any reasonable
> >>circumstance in higher power air-gap systems.
> 
> ------------------------------------------------
> 
>   Did these tests quench dampened waves or pulsed waves?
> 
>   John Couture

Not exactly sure what you mean. You can turn a transistor off any 
time you like. I tried turning off at first primary energy notch,
first primary quarter cycle (thank heavens for parasitic zeners in 
the FETs), etc. It behaved just like a gap except it was a gap I 
could effect ideal quench/dwell times with. The test setup was a 
standard disruptive two coil system with k set to about 0.1

Malcolm