Re: grounding question

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: Mddeming@xxxxxxx 

In a message dated 10/7/06 11:58:45 P.M. Eastern Daylight Time, 
tesla@xxxxxxxxxx writes:
Original poster: John <guipenguin@xxxxxxxxx>

Thank you.

If I am going to have my coil running in a science room.... could I
use the metal sink pipe as RF ground?


Hi John,
The final answer to this is MAYBE, Much depends on the construction 
and layout of the building and if you are using the drain or supply 
line. Some water systems and waste systems use insulating flanges so 
the pipe you fasten to may or may not be grounded. Some systems run 
for significant distances through the building before going to 
ground. Think antenna with field linkage to nearby cables,or possibly 
with a long distance to ground, you could be putting a several 
hundred volt differential on the flush handle down the hall =:0 A DMM 
will tell you if the sink pipe(s) are grounded, but you will need to 
check the geometry to make sure the path of least resistance is from 
the coil to ground and not to anything else that may be 
"unofficially" grounded to the same pipes. (esp. phone lines in older 
buildings that are notorious for being connected to things they 
shouldn't) Someone holding an ungrounded flush handle while 
depositing acidic material into a grounded drain line (like a urinal) 
makes an interesting voltage detector. ;-)))

Matt D.