Solder Mask pattern question

[NorCalAudio]

I have a couple PCB's for a Pass pre-amp I bought several years ago off a fellow in Croatia along with a parts list. I sourced the components a while ago and I now have time to assemble the boards.

My question is: I have 4 zenner diodes to drop in. I know the polarity of the diodes, but on the circuit board there are no polarity markings like a + or -. For each diode there is a round through hole and a square through hole. Going off the round vs square through holes, is there a way to tell what the polarity should be on the board?

Thanks,
pat

 

[BrianL]

Generally the square pad is the cathode -- i.e., it matches the end of the diode with the stripe.

 

[NorCalAudio]

Thanks.