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.

5V x 10 A regulafot (CB9960E)
This configuration appears elsewhere on this site. We found it in a Motorola manual from the 70s....
Integrated Circuit MC1648 Transmitter (CB19456E)
The integrated circuit used in this small transmitter is not very common today. The coil has its...
2 to 4-minute timer (CB20365E)
We found this timer circuit in an American documentation from the 1980s. The circuit uses the 6 V...