testing tubes...


is this possible to test tubes with only multimeter(VAO-meter)? i also know that completely blown tube will show very low grid-cathode resistance or grid-grid, but what about the tube that passes bias current through the grid(i.e DC?)
where i can get the pin diagram(s) of any particular valve(s)?
blowing tube or the one that is about to blow can cause different problems in the amplifier and needs to be checked/replaced prior to blowing.
128x128marakanetz
Just get a decent tube tester - money well spent. the time trying to do it with a multimeter is not worth it, not to mention you cannot do transconductance readings. About the best you could do would be filament tests.

-Ed
There is a plethora of RCA or Telefunken handbooks on Ebay , where you'll find all the pin diagrams and for the rest I suggest, you follow Ed's advice. Get a good old Hickock or Western Electric tube tester, there are lots of them on Ebay as well. The better ones are expensive though, because much sought after. Cheers,