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  #16  
Old 11-04-2010, 01:51 AM
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RitchieMars RitchieMars is offline
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Really? Huh... let's see. Trying this with a 6SN7, lowering the filament voltage sort of bumps it up a tiny bit, and then it drifts back to about where it was. A 6BK5 does about the same, it shifts but lingers about in the same spot, maybe just a hair higher. I also tried a NOS 12BY7 which reads around 68, also a very small shift. But... my 12AX7 tests good at about 60 with the filament set according to the manual, but if I drop it as you suggest... it's bad at 20 on both grids. That's the 12AX7 in my Zenith that controls the A.G.C and serves as the vertical oscillator.
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Old 01-01-2011, 03:44 PM
zapro zapro is offline
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Wow what a nice find! That's real bargain at 5$ apiece!

Well the reason that TV's does not use Electrostatic deflection for ther CRT is that if you were to deflect a 110° CRT electrostaticly you would need 7000-8000 volts to move the beam the +/-55°. It is not practically to do this.

The reason scopes used Electrostatic deflection is because it is linear, and way faster than magnetic. The magnetic deflection has a large inductance, and moving the beam fast requires a LOT of power.

// Per.
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  #18  
Old 01-23-2011, 10:34 PM
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Tube Radio Tube Radio is offline
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Also the larger the CRT the longer it has to be in order for electrostatic deflection to be used practically,
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