"Roy Hammond" wrote in message
...
Recently I purchased a new fluxgate compass (trademarked Williams F1 made
in
China) very neat, and cheap (£9.99). It works fine and calibrates well,
but
when the LCD blue glow backlight button is pressed, it lights-up for the
requisite 60 seconds or so, BUT the compass reading goes all over the
place - quite unusable! I guess that was why the compasses were selling so
cheaply in the store. Only for use in daylight!
The backlight is electrolumninescent and obviously is generating a
spurious
magnetic field. Has anybody any experience or ideas on how this problem
can
be overcome?
-Roy-
(Surrey, England)


check the battery or supply voltage when the light is on