Going to bring plane into a hanger in two weeks to paint wings. Have not looked at problem yet. I'm guessing flash tube. A bad ground would be cheaper and a blessing.
Anyone have a down and dirty method to check the flash tube?
E CHARACTERISTICS OF A XENON FLASH TUBE
• A xenon flash tube can be very photo-sensitive. One will flash
normally when exposed to an external light source, but may
become hard to fire when subject to darkness.
• They will become hard firing with age, or when exposed to very
high temperature. A hard firing tube will sometimes operate with
the engine running but will fail when operated on a low battery.
• They can develop a leak through eggshelling of the glass, or a
leak can develop around the seal of the wire to the glass. This is
caused by hot and cold cycling of normal operation of the system.
• They can go into self-ionization (continuously glow a light blue),
thus rendering the entire system non-operational until replaced.
This most likely occurs when the input voltage is highest. This
can be checked by turning the system off. When turning the
system back on, it generally will operate normally for a few
flashes before going back into self-ionization.
Any of the aforementioned conditions are reason for replacement
of the flash tube.
• To check a questionable flash tube, install it in a system and
apply 10 volts to a 14 volt system, or 22 volts to a 28 volt system.
If the flash tube will operate at the reduced level, it has a great
deal of service life in it.
A flash tube becomes harder to fire as it ages.
http://www.whelen.com/install/145/14578.pdf
