Neon tubes

Regarding Pip Laurenson's question about the construction and
properties of neon tubes, it may be worth posting the enquiry on the
sci.engr.lighting newsgroup, where there is considerable relevant
expertise.  While gas discharge tubes have a virtually unlimited
life when unused (other than by breakage of the glass or corrosion
of the external contacts), the glass slowly blackens with use due to
bombardment by the gas plasma, thus impairing their performance.

Dr. Nigel Seeley
The National Trust
36, Queen Anne's Gate
London, SW1H 9AS
+44 171 447 6521
Fax: +44 171 447 6540

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                  Conservation DistList Instance 9:62
                 Distributed: Thursday, March 14, 1996
                        Message Id: cdl-9-62-016
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