View Single Post
  #17  
Old 11-10-2008, 11:49 AM
Reece's Avatar
Reece Reece is offline
VideoKarma Member
 
Join Date: Jul 2004
Location: Cleona, PA
Posts: 2,178
The WD-11 tube is very delicate. Filament voltage is only 1.1 volts, less than a single flashlight battery, or dry cell back in the day (filament was lit through a rheostat on the radio to compensate for battery running down.) The attached shows the basing diagram and tube characteristics. I wouldn't use an ohmmeter on it directly because you don't know what voltage it might impress on the filament. Safest way would be to put a resistor of a few hundred ohms in series with the ohmmeter and check the filament that way. Any reading at all would mean you had continuity. At the same time you could check between the other elements to make sure none of them was shorted to another.

If you can clean the set up and then draw the circuit diagram, we could advise how to try it out. Should be pretty simple. Battery requirements should be 1.5 volt D cell for the filament, and three 9-volt batteries snapped together to yield 27 volts for plate.

Reece

http://www.nj7p.org/Tube4.php?tube=wd11
__________________
Reece

Perfection is hard to reach with a screwdriver.

Last edited by Reece; 11-10-2008 at 11:57 AM. Reason: Link added.
Reply With Quote