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Today I replaced the caps that were not mica, ceramic, or electrolytic. The Sams photos show bumble-bee (black beauties?) where my set had mainly Sprague orange-drops and brown-drops plus a couple of other tubular caps. I think the cleaner looking orange-drops were recent replacements as most of the orange-drops had a dirty film on them. Most of the orange and brown drops had leakage of around 1-15 uA at their rated voltage and some measured outside their uF tolerance, .0068 C46 was .0087, .15 C6 was .206, .056 C129 was .0647, and a couple caused my Sencore LC75 to not read properly even when out of circuit. I replaced them all with in tolerance valued capacitors, not wanting to trust 50 year old caps.
I started the first of the three multi-cap electrolytic can capacitors and found that the section labeling (square, triangle...) on my capacitor can does not match the Sams, but the chassis was wired as the Sams shows. So my capacitor values do not match those shown on the schematic or the parts list. I don't think this is a Sams mistake, for the following reason. The Sams schematic shows C3C as a 4 uF 150V cap with a blank label marking. The Sams shows that section wired as the cathode bypass cap of the V7 AGC tube with 35V across it. My set does have the V7 AGC tube wired to the blank labeled section, but in my can that section is a 40uF 25V cap. Which puts a 25V capacitor where Sams shows 35V. Here is what the Sams schematic and parts lists as the sections and what my can has:
Section Sams My set
A (square) 50uF 450V 20uF 450V
B (triangle) 40 uF 25V 4 uF 150V
C (blank) 4 uF 150V 40 uF 25V
D (1/2 round) 20 uF 450V 50 uF 450V
Ok, what am I missing here? Is it just a Sams error? But if so, then why does my set have a 40 uF 25V section connected to the V7 AGC cathode which Sams shows at 35V, unless that Sams measurement is wrong....
Also, Sams shows the 50 uF on the screen of the audio output tube, but the 20 uF on the power input to the vertical output transformer. Wouldn't it make more sense if the vertical output transformer power had the 50 uF and the audio output had the 20 uF? Should I just wire it as original?
Dave
Dave
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