I would appreciate it if someone would explain the circuit to me. What is going on, why not just send the voltage through to the NiMh battery? I assume it is to keep from over charging it the battery.
I am looking for a transistor that has the markings So550 or S0550. It is >in a telephone charging circuit consisting of only five parts. The other >parts are a 2n3906 transistor, two resisters and a capacitor. The circuit >is to charge a NiMh battery. > > I am no engineer, but I think I have it figured out There is 12 VDC past > the 2n3906 going into the So550, but nothing coming out, so I am assuming > the So550 is the problem. I have checked cross references and found > nothing. > > I have attached a crude drawing of the circuit the first transistor is the > 2n3906 and the second is the So5505. I have about 12 volts DC on both > connections going into the So550, but nothing coming out. > > Does anyone have any suggestions on where I could find the part or a > substitute? > > Thanks, Bill > >