10-03-2016, 09:26 PM
Ah HAH! A Precise 111 tester.
Those are an excellent instrument. In my opinion, they can do everything a Hickok 539 can do. AND it uses a 5KHz signal to develop Gm, vice the 60Hz signal used by nearly every other tube tester manufacturer except Weston.
If you have the opportunity, try using a solid state replacement tube for your 5U4 tube in the Precise. Without the 3A filament drain on your transformer, the instrument is able to measure high current tubes with less "sag," as it uses the "Hickok circuit."
Those are an excellent instrument. In my opinion, they can do everything a Hickok 539 can do. AND it uses a 5KHz signal to develop Gm, vice the 60Hz signal used by nearly every other tube tester manufacturer except Weston.
If you have the opportunity, try using a solid state replacement tube for your 5U4 tube in the Precise. Without the 3A filament drain on your transformer, the instrument is able to measure high current tubes with less "sag," as it uses the "Hickok circuit."