This 6-transistor commercial radio with 6 V supply was found in a Japanese publication from the 1960s. The circuit is a commercial superheterodyne with 150mW to 200mW of battery powered output.
This circuit uses two Raytheon RC4558 operational amplifiers that are similar to the 741. The...
This small stereo amplifier for headphones was found in a documentation on integrated circuits from...
This is a MOSFET version of a grid dip meter for frequencies between 1.8 MHz and 150 MHz,...