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NEON- Sintering and burning



<<Ed also mentioned burning the coating during bombing.  I know that I've
done this on occassion and am curious if anyone could speak to this.  At
what temp. does this happen.  I know that when I've made the error and done
this, it's a result of bringing the glass temp. up too fast and then having
to heat the electrodes after the glass has reached temp.  So, the glass
ends up getting hotter than it should.  What's the upper temp. limit for
damaging the phosphor in precoated tubes, does it vary by manufacturer,
phosphor, etc.  I'd say from my experience I've seen it happen around a
tight window within 250-275C, yes/no/higher/lower?

Thanks,

Tom U.>>>

Reply from dirk.
The glas temp is not so important in this matter. 
When you heat up the glas, you are in fact heating up the gass, 
and therefore the glas will always be slower and behind the gas temp.
When the gas is over 800 C the grain can be deformate, and again the cheap
and instable halophosphates are coming first. For the primaries from the
three wave band activated with rare earth the temp can rise over 1000 C before
they can deformate. 
Don't think that one cannot reach that high degree as it is easy done.
Be awre of the fact that when the tube is 250 C the gas temp is already
550 C and this line is not linear.
Hope that the above makes some things more clear, is signing with his
Best regards 
from dirk a. boonstra