Found in an Elektor from the 90s, this circuit converts signals from the 280 kHz band to 516 kHz, making it possible to tune them in common AM radios. The components used are from that time.
The National Semiconductor LM675 operational amplifier can provide up to 3 A of output current. In the...
We found this circuit in a 1969 Mullard documentation. The same configuration appears elsewhere in...
Found in a PE Hobbyst Handbook of 1991, this circuit was originally proposed to time photographic...