Prototype 1 - GaryLazerFinz/ECE-411-Capstone-Practicum GitHub Wiki

The first iteration of the project. We used recommended setups for the parts we had alreafy.The sensor may be a simple voltage divider that the ADC pin of the PICAXE will read. We haven't found a sensor so i will use an a potentiometer in its place. Here it is represented by the 1k resistor.

The motor was driven with a TIP 125 PNP transistor and a 2N2222 NPN. I used 1k ohm and 100 ohm resistors to limit the current. Later the 100 ohm resistor was bypassed to make it actually work. The 2N2222 might not even be necessary with 5 volts. This setup also requires the PICAXE pin to be off to turn the fan on. A diode disipates the residual EMF from the motor, protecting the PICAXE chip.

The chip will probably be permanently mounted to the pcb. The ability to easily reprogram the chip will be extremely useful.

The final ugly prototype.

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