This peak indicator for stereo amplifiers uses a CA3130. The 80's circuit does not need a symmetrical power supply.
This circuit was obtained in a Hands-On Electronics from the 90's. The circuit turns on one LED at...
This circuit makes use of an integrated LM2907. The circuit is from an old documentation being...
This circuit simulates a unijunction transistor with two bipolar transistors. We found it in the...