This is Dan Armstrong Green Ringer guitar effect for your electric guitar. The guitar effect is sold at high price at the market. Now, you can build your own low cost guitar effect… 🙂
The transistor marked ” * ” has no markings other than three stripes: green, blue and white from top to bottom. It is probably a log gain NPN used as a dual diode with the anodes connected together at the base of the final transistor.
The continuity test on the device shows no conductivity except that the topmost pin conducts when it is positive of the pins in the middle and other side; otherwise, no conduction. This? is I would expect if it were an NPN with the same pinout (base, collector, emittor) as the other transistors.
This circuit operated with 9V supply. Use battery or regulated power supply for better result.