Building an Air Sampler

The device consists of a timer-controlled fan used to create an air sampler in which constant airflow is produced over a sticky tape.

The project includes a box with 6 buttons and 2 PCBs with LCD display module with backlight. The PCB was upgraded to a LED-capable version so that it can support the LEDs and hold them in the right place, a few millimeters behind the display window. One small LED would show on the front console to indicate if the fan is running. The blue connector to the left of the LED displays indicates the other component that is still in use. This is intended to plug into the buttons embedded into the front panel.

A small board holds the PIC along with the power supply, LED, and fan power control electronics. A small piece of green plastic underneath the front panel window is attached to improve the things even better while painting parts of the board black. The metal plate that hides the PIC is an improvised heatsink for keeping the voltage regulators cool. A floppy cable externally connected will be used for programming the PIC without opening the box ever.

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