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Originally Posted by Geist
...I have been trying to work my way thru each wire and each section one at a time.. I have at present as stated above 230 Volts and that is without the focus coil and the Resistor dividers and the Centering pots..
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???Are you saying the focus coil and resistors R185a, R186a, R186b are not in-circuit? If so, then there is no path to ground for the center tap of the power xfmr. The CT has to have a path to ground before the 5U4 can supply the correct B+ voltage. Or is the focus coil simply unplugged, leaving R182, R183, and the focus control still in-circuit?
Again, what is the resistance between the power xfmr CT and ground?
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...With the second Rectifier plugged in the Voltage dropped to 200 Volts on pin 8.. And the Bulb lit up.. I took out the Bulb and left the rest the same, it now reads 270 Volts at pin 8.. Which is close to the 300 volts specified, for that pin..
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Probably the filament load of the second 5U4 lugged the primary down, lighting the Bulb and dropping the secondary voltages.
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So now my Question, Should I leave out the Bulb or for safety sake keep it in for the present while I am testing ???
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For now, leave the Bulb in, stay with a single 5U4 until you find out the resistance between the power xfmr CT and ground.
Once you verify the CT has the proper path to ground, stick both 5U4s in and get rid of the Bulb, and bring the primary up slowly toward full line voltage while monitoring the B+ at pin 8 (being sure not to exceed voltage rating of the new filters).