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Need Help with 49-405 Electronics
#5

Hi Wink,
I'm Not quite sure what you are asking but the B+ returns to B- though the the tubes conducting. B+ is applied the plate of the tube as the cathode heats and emits electrons. The plate having a high dc potential (B+) the positive electrons are drawn to the plate. The grids just control the amount of electrons that get from the cathode to the plate. The more electrons that hit the plate the more conduction (current flow from B+to B-) The cathode is at B- more or less. (Usually though a low value resistor)

I think what you maybe asking is if I measure from chassis to B+ I'm not seeing the proper resistances. Because B- is not connect to the chassis is floating. B- is actually where the - side of the filter cap are connected. Use that for your - meter connection when measuring dc voltages.

Have a stupid question for you did connect that cap with the coil around it back up?? Doesn't have to have the coil.

Terry


Messages In This Thread
Need Help with 49-405 Electronics - by Winky Dink - 11-08-2015, 04:03 PM
RE: Need Help with 49-405 Electronics - by Radioroslyn - 11-12-2015, 07:52 PM
RE: 49-504 Trimmer Trouble - by Winky Dink - 11-19-2015, 04:18 AM



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