Two-channel peak indicator (CB21975E)

This peak indicator for stereo amplifiers uses a CA3130. The 80's circuit does not need a symmetrical power supply.

Headlight Alarm (CB26300E)
Found in the Radio Experimenter Handbook in a 1986 edition, this circuit warns when the car's high...
bq7790x Battery Protectors ICs (COM059E)
August 2016 - It can be obtained from Mouser Electronics the battery protectors series bq7790x of...
SCR Alarm (CB13379E)
This circuit was obtained in a technical documentation on SCRs of 1976. The circuit can be...