usmanalifarooq
Newbie level 2
This is the Eti 549 metal detector circuit I'm referring to. I'd really appreciate it if someone could guide me and tell me what's exactly happening in the transmitter section. The first stage is a relaxation oscillator producing 800 Hz which is being fed into the next stage, which is a Colpitt's oscillator, which modulates the signal to 130 Hz...is that right? How exactly is that happening?