Turn-key PCB assembly services in prototype quantities or low-volume to mid-volume production runs

Tiny annoying buzzer

Do you get disturbed by unnatural sound? Take a look, there might be annoying buzzer hidden near by. If you are lucky not to have one, then be nasty and do this crazy prank to your friends. Chris have put a small buzzer which generates short sound bursts every few minutes. The pulses are short and scattered in time so it would be hard to track the source. Its small size allows to dig it deep in room mess. Buzzer is based on PIC10F202 microcontroller, coin cell battery, switch and speaker from small headphone. The PCB is practically same size as battery. No matter how tempting is to place this thing everywhere around, be responsible and creative. Continue reading

Play your favorite tune with a microcontroller

The tune of a song is made of various musical notes. Each note is played for a certain duration and there is a certain time gap between two successive notes. If the notes (frequencies) and the timing information are known, a microcontroller can be programmed to play the tune. This projects describes how to play the “Happy Birthday” tune with a PIC microcontroller. There are only two components used: a PIC12F683 microcontroller and a piezo buzzer. The microcontroller runs with a 4 MHz internal clock. Due to its high impedance the piezo buzzer can be driven directly from a PIC I/O pin. The author also provides the demo program written in MikroC which can be easily modified to play any other tunes. You can find the frequencies of various musical notes here. Continue reading