02-18-2011, 05:01 PM
The transformer is the audio output transformer which matches the high impedence of the tube to the low impedence of the speaker and is required. I think it still may be OK, Here's how you check:
Measure the resistance of the primary (blue and red wires.) Should read aeround 100 ohms or so. If it is open, the news is not all that good. The other two terminals go to the speaker. The measured resistance will be 1 ohm or less. Finally, check to see if the red or blue wires shows any shorts to the speaker windings or the metal transformer casing. This would not be cool. The speaker (secondary) winding probably does have one side connected to the metal base, and that's OK.
Assuming all is well, you of course will have to splice long lengths of blue and red wire (strranded, please, and use heat shrink tubing.) The schematic will tell you where to hook them up. The blue one will go to the plate of the audio output tube, and the red one will go to the same B+ connection the old wire went to.
Keep us posted
Measure the resistance of the primary (blue and red wires.) Should read aeround 100 ohms or so. If it is open, the news is not all that good. The other two terminals go to the speaker. The measured resistance will be 1 ohm or less. Finally, check to see if the red or blue wires shows any shorts to the speaker windings or the metal transformer casing. This would not be cool. The speaker (secondary) winding probably does have one side connected to the metal base, and that's OK.
Assuming all is well, you of course will have to splice long lengths of blue and red wire (strranded, please, and use heat shrink tubing.) The schematic will tell you where to hook them up. The blue one will go to the plate of the audio output tube, and the red one will go to the same B+ connection the old wire went to.
Keep us posted
