Metal detector receiver (CB22457E)

Found at Popular Electronics this receiver is used with a transmitter for quadrature-coil signals.

Power Stage for CMOS Circuits (CB12727E)
In the figure we give a suggestion of a high-power stage to excite a speaker with the 2N3055. The...
Wireless Waa Waa Pedal (CB6879E)
This guitar pedal was found in a 2004 documentation. The signal is transmitted to an FM receiver...
1 kHz Low Pass Filter LM3900 (CB14188E)
The circuit shown below is from the National Semiconductor's 1994 Linear Applications Handbook. The...