Re: Ground box

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Terry Fritz" <twftesla-at-uswest-dot-net>

Hi Malcolm,

I am using the outer braid of the heavy coax (it is braided) for things
like motor case ground, NST ground, safety gap ground.  I would be using
the center conductor (heavy stranded wire) for the "RF" ground for the
secondary base.  Thus, the low frequency stuff like AC faults and such
would go through the outside braid while the RF currents go through the
center conductor.  I was thinking the radiated RFI from the long secondary
base ground would be somewhat shielded buy the outer braid.  It was just
one of those thoughts that "looked" good so no guarantee that it is any
good...  Perhaps, the RF strike rails and safety gaps should go to the
center conductor too?

Cheers,

	Terry


At 11:44 AM 4/6/2001 +1200, you wrote:
>Hi Terry,
>           If the outer is braided, it will be probably the worst 
>ground conductor you can get.
>
>Cheers,
>Malcolm
>
>On 5 Apr 01, at 15:59, Tesla list wrote:
>
>> Original poster: "Terry Fritz" <twftesla-at-uswest-dot-net>
>> 
>> Hi All,
>> 
>> I have been using the following ground system:
>> 
>> http://hot-streamer-dot-com/TeslaCoils/Misc/GroundBox/Diagram.jpg
>> 
>> It is basically a length (40 feet) of RG-8U coaxial cable.  One side
>> has both the inner conductor and shield connected together to a cold
>> water pipe.
>> 
>> http://hot-streamer-dot-com/TeslaCoils/Misc/GroundBox/PipeConnection.jpg
>> 
>> The other end has the shield connected to a metal box and the inner
>> conductor connected to a terminal.
>> 
>> http://hot-streamer-dot-com/TeslaCoils/Misc/GroundBox/InsideBox.jpg
>> 
>> http://hot-streamer-dot-com/TeslaCoils/Misc/GroundBox/TerminalBox.jpg
>> 
>> The idea is that safety and general grounds can be connected to the
>> box/cable shield while the noisy secondary ground connection can
>> connect to the terminal.  Thus, the base ground lead currents will be
>> somewhat shielded buy the outer conductor.  The other general
>> grounding is through the shield.  I measure 0.2 ohms between the
>> ground box and the AC line ground at my control box.
>> 
>> I know this subject came up last month and I was wondering if this is
>> seems like a good idea or not.
>> 
>> Comment/thoughts/suggestions...
>> 
>> Cheers,
>> 
>>  Terry
>> 
>> 
>> 
>
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