Sencore Mighty Mite....Why are all tubes testing the same??? - Videokarma.org TV - Video

Magnavox300 · #1 10-21-2012, 01:20 PM

This is my 2nd tube tester I have purchased in the past month, and this one doesn't seem to be working either.
Does anyone know why every tube I test in this measures the same exact emission? The needle always falls in the same exact spot between ? and good.
I did notice a small capacitor, 50uf/50v, inside;
would changing that help?

Magnavox300 · #2 10-21-2012, 08:07 PM

Also, I tested about 12 tubes with this.
A couple I knew were bad, or thought so anyway.
All my projects have been on hold due to these testers not working properly....
Any advise would be greatly appreciated!

Magnavox300

*zenithfan1* · #3 10-22-2012, 09:16 AM

Changing that cap might help, my tester had a few caps go bad and it works much better after changing them. If anything, it can't hurt it any to change it.

N2IXK · #4 10-22-2012, 09:24 AM

Is there any setting you can make (line adjust maybe?) that will move the needle on the meter past the point in question? I'm wondering if the meter movement is mechanically obstructed at that point by a bit of dirt or something...

Magnavox300 · #5 10-22-2012, 01:04 PM

Quote:

Originally Posted by N2IXK

Is there any setting you can make (line adjust maybe?) that will move the needle on the meter past the point in question? I'm wondering if the meter movement is mechanically obstructed at that point by a bit of dirt or something...

That's what I was thinking, I am going to take the meter out and check it....
Thanks!

electroking · #6 10-24-2012, 02:09 PM

Before you take the meter out, try testing 'no tube at all'. If you still get the same
reading, it means you were not testing the tubes, bet getting a reading due to
some malfunction. Otherwise, the idea of a jammed meter becomes more
likely. Good luck!

dieseljeep · #7 10-24-2012, 08:48 PM

Quote:

Originally Posted by Magnavox300

That's what I was thinking, I am going to take the meter out and check it....
Thanks!

If the meter comes to an abrupt stop, then there would be mechanical binding. Don't know that it would happen to two of the same instruments.
The Mighty-Mite checker is one of the better small emission checkers out there, but it is still only an emission checker.
IIRC, they tie all the elements together and check the tube as a rectifier.
They were good for weeding out the real weak or dead tubes. Also for leakages or shorts.