Not made to be taken apart. Long rivets and star circlip. Unusually ,
constant but fairly low level of crackle over 80 percent of one track.
Presumably loss of
plating on conductor track so varying different metal Seebeck voltage or
chemical
corrosion perhaps .


--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/