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Info

Buzzer v2.5 with Amplifier

Buzzer v2.8 PCB: Top

PCBs are out for manufacture

Eagle CAD: v2.8 Schematics

Eagle CAD: v2.8 Bill of Materials (BoM)

Arduino Sketch:  HappyBirthdaySong.ino

Description v2.8:

Magnetic audio transducer, a.k.a. buzzer speaker.

Redesigned with an adjustable 700mW amplifier that can handle a broader audio range than a standard piezo.

Features v2.8:

 - Board size reduction makes it breadboard friendly

 - 3.3v or 5v operation

 - Most parts are SMT and spaced adequately for easier soldering

 - Redesigned so pin headers could be used to attach it to a backpanel PCB