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What the numbers 1 and 2 mean next to Crystal oscillator in hardware schematics? I tried to search online and went through about 20 lists with component symbols, but non had the numbers nor description about them.

He's a picture.

Crystal oscillator with numbers 1 and 2

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Note that depending on the crystal footprint, you will see crystals with 2, 3 or even 4 pins on the schematic. The other pins may or not be connected to anything, and are generally just supports for the crystal case. – Connor Wolf Feb 2 '14 at 5:58
up vote 6 down vote accepted

Since crystals usually do not have a polarity, they're just there since the CAD tool requires pin numbers for generating the PCB or writing netlists for simulators.

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Thanks, I was thinking that too, but as i'm a newbie just wanted to check for sure. Big thanks. – user2570174 Feb 2 '14 at 3:36

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