Hi All,
I have a question about using a PIC 12c509 to produce a steady tone. 
I wired up a simple circuit that uses a normally open switch on input GPIO0 and as long as the switch is pressed the PIC would produce a square wave out GPIO2. I connected a piezoelectric transducer to that pin and everything worked fine. (I was proud of myself) I then replaced the piezoelectric transducer with a 10Kohm to 10Kohm impedance matching audio transformer and connected this to the input of a PA system through a 1/4 inch jack. The response was "Nothing came out of the PA". Where is the problem? Is the 10K too high? Is the 5v square wave not enough amplitude? Any help would be great.

Troy Powledge
TCo. Systems
tpow@eramp.net