capacitor polarity

[sinclairuser]

hi all i found a video that might be useful to our projects, it relates to the polarity of capacitors specifically types that are not normally considered to have a polarity.
normally polystyrene or polypropylene type caps are not considered polarity dependent, even though they are, one lead will connect to the outer end of the material the cap is made from this should go to the ground side of the circuit, this gives maximum shielding to noise and hum.
most every day circuits this will not matter, but amps and receivers and sensors can benefit from checking the caps.

the video explains this concept and even gives a test circuit you can build, though any scope will show the low amplitude side of the cap under test.
i use this approach now and i figured anything that can help reduce noise in our detector circuits must be a plus.
https://www.youtube.com/watch?v=BnR_DLd1PDI

[Polymer]

Great Info. I love little tidbits that widen my perspective. Thank You!

[Skippy]

Another odd capacitor characteristic for you: they can couple with each other, as they are unshielded. If you have them too close, for example nicely lined up next to each other, signals from one can pass to the others, eg. Left and Right channels in audio gear. Detectors are a likely place to have this problem, as they are high gain, high enough frequency, have small signal levels, and are noise-sensitive.
Cures involve mounting them further apart, mount them at 90 degrees to each other, mount them on opposite sides of the PCB, fit a screen between them, eg brass / tinned-steel sheet, copper-clad PCB material.

[Davor]

Or just keep everything low impedance and forget about it. It is also beneficial for noise issues.