Williams Power Supply (Robotron, Joust etc.) cap @ C13...which way is positive

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Williams Power Supply (Robotron, Joust etc.) cap @ C13...which way is positive

Recapping a Williams power supply...I've gotten to cap @ C13...I can't tell from the original cap which way was positive or negative and the bottomside of the board doesn't show polarity for that spot. Tried to find a quick schematic but I'm not having any luck...does the positive side face the outside of the board or towards the inside for this location?? Thanks in advance!
 
Recapping a Williams power supply...I've gotten to cap @ C13...I can't tell from the original cap which way was positive or negative and the bottomside of the board doesn't show polarity for that spot. Tried to find a quick schematic but I'm not having any luck...does the positive side face the outside of the board or towards the inside for this location?? Thanks in advance!
It could be a non-polarized cap. Meaning it can be connected either way in the circuit. I'm not saying it is, but I have run across a few caps like this that don't show the orientation of the cap.
 
It could be a non-polarized cap. Meaning it can be connected either way in the circuit. I'm not saying it is, but I have run across a few caps like this that don't show the orientation of the cap.

I'm pretty sure it's polarized. One side has a black line going down it from the original cap but it doesn't show positive or neg. The other original caps show plus signs going down the side with a black line down the size but this one cap just shows a black line...weird.
 
It is polarized. I don't have one handy, but looking at the schematic, the + side of the capacitor goes to pin1 of the 7906 voltage regulator Q5 and pin 1 of bridge rectifier BR3. The negative side goes to pin 2 of Q5 and pin 3 of BR3.

As I recall, the capacitor holes are not marked, but if you trace back to BR3 the outputs are marked with polarity.

If that isn't enough for you to figure it out, let me know and I'll pull one out of the box and verify it for you when I get home from work tonight.

ken
 
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