tube works?

[changes]

i checked the the filaments of a tube with a DMM ,pin4 and pin5 (there's no tap) and it beeps...(they connect to each other)
is this ok?

[Mike Burgundy]

wel, yes, but that's no indication if the tube works. If it were open (infinite resistance) it WOULD indicate however that the tube will not work.
The filament is comparable to the one in a lightbulb - it conducts a reasonable amount of current, but has a (smallish, in this case) resistance so it gets hot.  A lightbulb filament gets hot enough to emit a lot of light, a tube filament gets hot enough to warm up the cathode enough to start letting go of electrons.
If a conductor gets hot, its resistance goes up, so a cold filament will always have less resistance than it should have in operation.
There's loads more to this, but yes, pin 4,5 and 9 should connect to each other through a small resistance. On a 12AX7, that is. No center tap? Different tube huh? If youre sure those are the filament pins you should be ok.
hih