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 amplifier for hearing aid was found in a 1968 documentation using an integrated of the time....
We obtained this circuit from a 1993 documentation. The circuit has 9 current ranges that are...
In the figure we have the transmitter of a data transmission system with optical fiber suggested by...