From: 	Micheal Huff[SMTP:msnock-at-theonramp-dot-net]
Sent: 	Thursday, June 19, 1997 1:42 PM
To: 	Tesla List
Subject: 	Re: Chokes

Tesla List wrote:
> Subject:  Chokes
>   Date:   Tue, 17 Jun 1997 14:32:56 +0200 (SAT)
>   From:   Richard <esmit-at-ilink.nis.za>
>     To:   tesla-at-pupman-dot-com
> Hi, guys
> I have a transformer of 15000 VAC 30 mA and want to build a choke for my
> transformer. (I don't know much about chokes) Can anyone give me info on
> how
> to build it, the reason I'm asking you is that I can't unzip some of the
> files on ftp.funet.fi

Ferrite, toroid shaped cores are normally used but you can use the
ferrite stick from an AM radio.  Wind about 300-375T on the stick with a
wire with appropriate ampacity (no. 24 should work fine.).  Wind two
chokes.  Place each between the safety gap and the main gap(s).  Neons
are very sensitive to high currents since their secondaries are wound
with very thin wire.  Make sure the main spark gap and the safety gap
are in parallel with the transformer.  This will short out a lot of the
RF that is heading toward the transformer.  The coil must also be in
rough tune when it is powered up.  Start by finding a good tune with a
lower voltage and or current transformer or use a variac to slowly bring
the power up until you know it is in good tune.

Here's some nice ASCII art to show you where the chokes go.
          (------+---^^^^----+--> to rest of tank circuit
-------)||(      |           |
       )||(      0safety     0
       )||(      0gap        0 main gap(s)
-------)||(      |           |
         |(------+---^^^^----+---> to rest of tank circuit
         |          choke

The center of the safety gap should go to ground as well as the neon

> I really don't want to buy a new transformer if something goes wrong.

Who does? :]


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