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41-287 No voltage from secondary of transformer
#1

Hello, After wiring in a electrolitic capacitor the wrong way I fried the strip resistor (labled 61 on schematic) so I corrected the mistake with another new ecap and replaced all three of the resistors with 100w ceramics.
the damage also included the 84 rectifier tube which I also replaced. Now all I get is filament voltage out of the recitifer curciut. The transformer is not burnt nor is it leaking. The resistors I refered to replaced the 146, 31 and 15 ohms labeled 61 with part # 33-3393 . I hope this is enough information for you. Thanks in advance for any help. JEP
#2

Hello and welcome.

What kind of voltage do you get when you measure from plate to plate of the 84 rectifier tube? (Tip: Measure this as AC volts, not DC volts.)

If you are not getting anything here, chances are the power transformer is dead even though it did not smoke or leak wax.

Be careful! That AC voltage will be around 525 volts if the transformer is working!

Also, how did you replace the Candohm resistor? With individual resistors? Did you remove the old Candohm (multi-section resistor) from the circuit entirely?

--
Ron Ramirez
Ferdinand IN
#3

Hello Ron, Thanks for the fast response. To answer your question, I measure 532 vac across the plates of the 84 rectifier tube. The schematic shows 265 vdc across the 12uf ecap. Having replaced it with 22uf I show 360vdc and across the 16uf ecap the schematic indicates 180vdc. With the replacement 22uf ecap item 27A shows neg 56. Also you asked about the Candohm resistor, yes, I removed the entire piece and replaced it with separate 5 w ceramics of 15, 33 and 150 ohms. I also noticed an error when I changed the 12uf ecap - I had the negetive side to ground rather than the center tap of the transformer. So, no sound no smoke just filament and indicator lights. JEP




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