newshound wrote:
wrote in message ...
On 9 Apr,
wrote:
Of course, that completely ignores the false negative potential for
them, and that is the real problem with them.
you should always test the tester before /and/ after use, which will
minimise
false negatives. If you understand how they work, /and/ their limitations
you
can't go far wrong. This applies to all test proceedures.
--
B Thumbs
Change lycos to yahoo to reply
Well said. Did anyone actually answer the original question? The neon tube
is in series with a big resistor, about 1 Megohm if I recall correctly, so
that only a fraction of a milliamp goes through you; this does you no harm
but is quite enough to light up the neon.
I used to use one about 30 years ago until I received a belt of it, duly
consigned to the bin.
Nowadays I use a pen sized non contact tester for a quick check (always
check it first with a known live)If it gives so much as a single beep
out comes the meter.
Bazza