Fan Relay Board etched and populated….

  After using the toner transfer method to apply the circuit to the bare pcb, I began the etching process.  Using the same batch of etching solution from before, I noticed the process was quite a bit slower.  I left the board in the etchant for at least 30 minutes.  I was a little worried at first, but relived when the copper finally started to disappear.  
Once I began to place the components I had noticed that the transfer was printed upside down…luckily the circuit is simple and works both ways with the relay being the only thing that had to be soldered on the opposite side. 
Also replacing the NPN transistor with a PNP type, allowed the transistor to switch a grounded supply.  I don’t know why this problem eluded me before; I should of realized that a PNP transistor should be used in this situation. This probably would have fixed the initial problem, but adding the relay gives me a little more control over what is going on. 
Once everything was soldered, I connected the boards and placed them into a small black case used for storing static sensitive devices….which were free from Microchip.
Now I just need to hook it up to the car one more time for a test run and the controller should be finished.

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