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Old 02-26-2015, 01:34 PM
old_coot88 old_coot88 is offline
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Join Date: Sep 2009
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Quote:
Originally Posted by whatadish View Post
...I am at somewhat of a loss to explain the lack of my -45v at pin 5 of the 6dq6. Can someone tell me where that comes from.
For simplicity, think of the cathode and grid of the 6DQ6 as a simple diode rectifier. That's what the drive signal "sees". The "diode" can conduct in one direction only, cathode-to-anode. An excess of electrons, which equals a negative charge, appears on the grid. So voltage on the grid ('anode') is negative relative to the cathode.

In early radios, the same principle was called 'grid leak' detection.
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