Capacitor question

[AlexBellamy]

Hey guys, I have a question regarding this build: http://diystrat.blogspot.co.uk/2011/05/building-quick-brian-may-style-treble.html

Concerning c4, the electrolytic capacitor. I know which leg is the negative one, but I don't know which way round the capacitor should actually be? For instance, the capacitor is being soldered to holes d6 and e6 on the veroboard, but which hole should the negative leg be soldered to and which hole should the positive hole be soldered to?

I apologise for what is probably a very obvious question, but thanks very much for any help you can give me! The build is going well so far, so I feel like I may slowly be getting the hang of it 

[Mike Burgundy]

Electrolytics should always be correctly orientated, + to the more positive side, - to the more negative. Since its a negative ground circuit, and one end of the cap is connected to ground, it's reasonable to assume - to ground. Looking at the layout it's a bypass cap for the emitter resistor (maximising gain fr the transistor), so yes, d6=+, e6=-
hih

[PRR]

Somehow that image has gotten washed-out.

In this software, as in some others, the NEG side of the cap has a dark mark.

Not so dark in the image you linked. However if I hold it to the light just right (or use a fotochop contrast tool) the dark-mark can just be seen:



Fortunately, this interpretation agrees with Mike's logical analysis.