I am not sure what is happening here.
I built the same old circuit, this time using a TL072 op amp. It worked perfectly.
Then, I received some plastic DC barrels (these ones to be precise).
I built the identical circuit, so that I can utilize my plastic DC barrels in this one. I followed my usual wiring , however, the circuit did not work. When I began measuring my voltages with a meter, I noticed that my voltage is not + 9 volts, but - 9 Volts.
I am pretty sure that the fact that the DC barrel is plastic, and it no longer presents the problem of trying to get it through the enclosure without it shorting, it likely has an impact on the way the volts are fed in to my circuit.
Presently, I have two wires streaming from the positive terminal of the DC barrel. One of these goes to the circuit board as the voltage supply, and the other goes to the top middle lug of the stomp box switch.
I then have two black wires running from the negative lug of the DC barrel. One of them goes to negative rail on the circuit board and the other goes to the negative lead of the LED that is supposed to light up each time the stompbox switch is on to activate the distortion effect.
Because I am using the plastic DC barrel, is this just a matter of switching the leads on the positive lug of the DC barrel to the negative lug of the DC barrel, and vice versa? Or is there more to it?
Note: The DC barrel has a positive leg, a negative lug and a ground lug. I initially was using the positive lug and the ground lug, but then I used the positive lug and the negative lug (rather than the ground), cause I thought this would fix things. I was wrong.
Your advice would be greatly appreciated