To polarize or not to polarize?

[Chris mudd]

Hello all,
Iam building the rub a dub reverb deluxe. I purchased a bunch of 1uf caps that are small yellow bulbs with one leg longer than the other. Now I am worried they are polarized.  

Are they polarized and can they be used in this circuit? There is no indication for polarized in the layout.

Can't help thinking the short leg is telling me something!

Thanks!


Chris

[Bolsyo]

It's a tantalum cap, and it's polarized: http://www.learningaboutelectronics.com/Articles/Tantalum-capacitor-polarity-markings

[nocentelli]

Chris mudd wrote

Are they polarized and can they be used in this circuit? There is no indication for polarized in the layout.

The schematic in the pdf for this PCB shows the 1uF caps as polarised and indicates their orientation:
https://1776effects.com/products/rub-a-dub-deluxe-pcb-only

[Chris mudd]

Thanks for the help!
Is there anything in this layout to indicate which way to orient the caps?

http://tagboardeffects.blogspot.com/2014/07/rub-dub-reverb-deluxe.html?m=1

[Silver Blues]

Tantalum caps are notorious for being very intolerant to reverse polarity; as a general rule, if you aren't sure which way they are supposed to be oriented, or if there's no indication of polarity, don't use them. If you do know the proper orientation then you're good!

Comparing the layout to the schematic, it appears that both capacitors should have their positive terminals oriented to the left.

[lasermonkey]

My first experience of Tantalum caps being incorrectly orientated was in my first job, as an electronics tech apprentice. Sometimes they'd go pop, blasting the top of the cap into space, otherwise they'd catch fire. It could be quite entertaining!
Definitely don't use them unless your're absolutely sure which way round they're supposed to go.