04-08-2014, 11:54 PM
Prior to applying power, I replaced all electrolytics, paper caps (tubular and Bakelite blocks), and any questionable resistors; checked every coil including the speaker for continuity and appropriate resistance; and tested all tubes for transconductance and emissions.
I believe I have wired everything correctly, but (you may find this hard to believe) I have actually made mistakes in the past. I can read a schematic pretty well, but when I get befuddled I resort to sketches.
[Image: https://lh5.googleusercontent.com/-r8rVl...520645.JPG]
The BC resistor and condensers 58, 59 were particularly troubling because the condensers has been replaced with a couple of cardboard electrolytics under the chassis, so the physical wiring was changed from the original. I also wasn't sure which end of the resistor was +, -, B, or C. I rebuilt new cans for 58 & 59, and rebuilt the 3-condenser can.
This is a before/after comparison. All replacement components are reproductions.
[Image: https://lh6.googleusercontent.com/-ihp5d...520645.jpg]
The power resistor has three terminals. On this picture, numbering the terminals from left to right as 1, 2, and 3; can you give me a designation for each terminal? I think I connected the middle one as C-. As for C58 and C59: I think the negatives are connected to the BC resistor and the positives to opposite ends of the field coil. The Philco schematic doesn't indicate (+) and (-) on the electrolytics.
I have to pull the chassis again, then start verifying my connections and check that I don't have any reversed polarities on the electrolytics.
Thanks for the help. It'll take me a few days to check out everything you've mentioned.
I believe I have wired everything correctly, but (you may find this hard to believe) I have actually made mistakes in the past. I can read a schematic pretty well, but when I get befuddled I resort to sketches.
[Image: https://lh5.googleusercontent.com/-r8rVl...520645.JPG]
The BC resistor and condensers 58, 59 were particularly troubling because the condensers has been replaced with a couple of cardboard electrolytics under the chassis, so the physical wiring was changed from the original. I also wasn't sure which end of the resistor was +, -, B, or C. I rebuilt new cans for 58 & 59, and rebuilt the 3-condenser can.
This is a before/after comparison. All replacement components are reproductions.
[Image: https://lh6.googleusercontent.com/-ihp5d...520645.jpg]
The power resistor has three terminals. On this picture, numbering the terminals from left to right as 1, 2, and 3; can you give me a designation for each terminal? I think I connected the middle one as C-. As for C58 and C59: I think the negatives are connected to the BC resistor and the positives to opposite ends of the field coil. The Philco schematic doesn't indicate (+) and (-) on the electrolytics.
I have to pull the chassis again, then start verifying my connections and check that I don't have any reversed polarities on the electrolytics.
Thanks for the help. It'll take me a few days to check out everything you've mentioned.
