Mystery flickering neons

[James Sweet]

Could be the neon gas is slowly vented to the outside and conversely
possibly some outside contamination gets into the envelope through the
seal in the glass/electrode interface, humidity comes to mind. The
electrodes may also vaporize a very tiny bit into the gas or become
pitted when the neon is hit by powerline voltage spikes. I recall neon
lamps sometimes being used as clamps around high voltage sensitive
circuits. And as Bob said the trace radiological striker has a shortish
half-life.

IIRC the electrodes are also coated with a substance that helps them emit
electrons, this wears out over time.

 

[Dave Moore]

"Sam Goldwasser" <sam@saul.cis.upenn.edu> wrote in message
news:6wn0bma2yf.fsf@saul.cis.upenn.edu...

Not quite sure what you question is but:

1. Neons when new don't flicker.

Well, yes they do,, but not noticeably ( negligible effect),
so for all practical purposes, yes, to the human eye, they
don't flicker

 

[Dave Moore]

Plasma Physics is not dead by any means.
it is in fact state of the art science these days.


"Bruce" <Montypythom@hotmail.com> wrote in message
news:3f9e4bca$0$21655$afc38c87@news.optusnet.com.au...

I think its wonderfull so many know about a technology that died around
the
first episodes of Star Trek
makes great reading !!

"Nigel Cook" <diverse2@tcp.co.antispam.uk> wrote in message
news:BoidnfghOJMw8QCiRVn-tA@tcp.co.uk...
I am aware that driving neons with DC not AC produces
a flicker effect (mock candle flame effect).
Just recently repaired an old Quad
valve/tube radio that uses flickering neon type devices
to indicate tuned in point.
For ages i've noticed the neon on my bench power supply
flickers according to what else is in use electrically.
A room lamp if on then neon goes out but as its on a dimmer
and i turn it down to 30% or so or less ,then the neon
comes on. Happens with ordinary filament lamps on
the lighting circuit - the ps is off the power ring main.
Just curious - any ideas ?

e-mail (removing .....) diverse2@tcp.co.u.....k
electronic hints and repair briefs , schematics/manuals list on
http://homepages.tcp.co.uk/~diverse

Nigel,Diverse Devices,Southampton,England

 

[Roy J. Tellason]

James Sweet wrote:

Could be the neon gas is slowly vented to the outside and conversely
possibly some outside contamination gets into the envelope through the
seal in the glass/electrode interface, humidity comes to mind. The
electrodes may also vaporize a very tiny bit into the gas or become
pitted when the neon is hit by powerline voltage spikes. I recall neon
lamps sometimes being used as clamps around high voltage sensitive
circuits. And as Bob said the trace radiological striker has a shortish
half-life.

IIRC the electrodes are also coated with a substance that helps them emit
electrons, this wears out over time.

Oho! A "cold cathode", is it?

I always wondered why those never caught on...