Measurement Techniques

To: "'Tesla List'" <tesla-at-pupman-dot-com>
Subject: Measurement Techniques
From: Tesla List <tesla-at-stic-dot-net>
Date: Tue, 18 Aug 1998 23:56:47 -0500
Approved: tesla-at-stic-dot-net


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From:  Malcolm Watts [SMTP:MALCOLM-at-directorate.wnp.ac.nz]
Sent:  Tuesday, August 18, 1998 5:42 PM
To:  Tesla List
Subject:  Re: Measurement Techniques

Hi Tony,

> From:  Tony Lekas [SMTP:tony-at-lekas-dot-org]
> Sent:  Sunday, August 16, 1998 1:46 PM
> To:  tesla-at-pupman-dot-com
> Subject:  Measurement Techniques
> 
> I am getting close to final assembly of my first coil and I am looking
> for information on measuring various characteristics.  I have a DMM.  I
> can borrow an I-Scope, a current probe, and a signal generator, but I do
> not have access to a high voltage probe.
> 
> The coil will be powered by 3-4 15 Kv 30 ma NSTs.  The secondary is
> 8.4"x40".  The cap is a .0228 ufd pulse discharge cap.
> 
> I have seen bits of information on this in other posts, but I am looking
> for more complete ideas on measurments.  There are many things I would
> like to measure but the following is an initial list in decreasing order
> of importance:
> 
> -Secondary coil resonant frequency
>     I plan to do this with the equipment I have
> 
> -Primary current waveform
>     I need this to monitor gap quenching.  I am using NSTs and don't
> have any part of the primary grounded.  How can I measure this without
> damaging the O-Scope?

Monitor the e-field using a scope aerial probe (if you don't have 
something as sophisticated as Terry Fritz's probes). For the primary 
alone, you will see the oscillations cease (at a pretty low 
amplitude). For the coupled system, the lack of a beat envelope 
signals effective primary quench. 

Malcolm
<snip>