"Arska" writes:

I have a flashtube (Novatron 2000/2001/2060, 500J 800V), but I don't know
the polarity .

Would you help me, is there any polarity of this tube, if there is which one
is cathode ??

I have two pictures of it :
http://www.kolumbus.fi/ari.n/valokuvat/flashtube01.jpg
http://www.kolumbus.fi/ari.n/valokuvat/flashtube02.jpg

I can't see any differences between the electrodes, can you?

* Any red markings or "+" markings indicate the anode.

* With no markings but electrodes of unequal size, the larger one is the
cathode.

* If both ends look identical but the trigger electrode is closer to one
electrode, or more coupled to one electrode, then that electrode is the
cathode.

* If the tube looks symmetric except for having a getter at only one end,
it is probably preferable to make the getter end the cathode, especially
if any getter material exists on the electrode itself. Any vaporized
getter metal forms positive ions easily, and will be attracted to the
cathode. Metal vapor released around the anode is more likely to condense
all over the tube and discolor it.

* If both ends of the flashtube look alike except for one electrode being
shinier and with rounded edges, then the shiny electrode with rounded
edges is the anode, and the steel-gray (tungsten) sharply cylindrical
one is the cathode.

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