I recently finished the core modual and measured the voltages after the 7805 regulator and noticed I’m getting a regular voltage of 5.4v to 5.5 volts. I don’t believe this is the proper voltage, and am wondering if its a problem with the 7805 or if its safe to use as is. The AC adaptor is measuring 9.4 volts before the rectifier, appx 11v after the rectifier, and then the 5.5 regulated supply. Thank you for your answers.
William
hummm if you can try to change the 7805…5.5V is high, but I don’t think it can damage any device… The voltage will go down when it will power the PIC and the 6N138. 
I was having problems with my 7805 regulating at 5v.
I am using a cheap protoboard to make my prototype, and I notice that the 7805 was too far in the board. After a little adjustment it worked fine.
The 7805’s can vary between one another, and if you damage them, they can start to regulate at higher than 5v!
Is it possible for a 7805 to regulate at 5v but give minimal current? I am having problems testing mine, any suggestions?