Reply To: Stark 12-22

[Ralph Spracklin]

Sterling. What was throwing me was the long 1/2 moon shaped contact strip was missing on the first pic you posted. I suppose it had fallen off. I did not realize that and thought the wafers were different! You say you never tried using the tester, and you were just going by what the repair Tech told you. Why did you not try it using the the Tube Tester with your Variac, using information given on pages 8 and 9 of the Manual. Maybe, just maybe there is no problem at all.
However you would need a tube to test that had a known short, in order to confirm if indeed it was working or not. Let me know if it still is or is not working after you have tested a tube with a known short. For the purpose of testing for shorts,you can always test any tube for shorts using a Continuity Tester.
To use this method, you check each pin against all other pins, checking for shorts/continuity. If when doing this test, if a short shows, you will already know the said tube is faulty. You must also remember that some tubes will have internal connections within the tube, with the other elements, which can seem like a shorted element. For instance sometimes, on some tubes the Cathode can be connected to one or two of the grids. Also I have seen some tubes where the Third Grid and the Plate are internally connected. This you should confirm, prior to testing with your meter. Always check your tube Data Manusl for any anomalys such as this. Also remember that the filament pins will also show as a short, using this method. Of course, in this case it is only telling you that the filament is working properly. On some tubes such as the 35W4, the filament will consist of three pins, so it is buyer beware! When using this method, use you meter with aligator clips on the pins. Tap each tube to see if the short is intermittant. This method is slow, but works well. However when using this method it is wise to do the test above, prior to testing the tube for other test tunctions on your tube tester. Of course, there could also be other problems with your Tube Tester, but let us know how it all works out.

Ralph