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.
Because it uses TTL integrated circuits, this siren must be powered by 5 V or as indicated with D1 to...
The correct connection of speakers and tweeters in a speaker to obtain better sound quality,...
The CMOS PLL used on this circuit is not very common. The circuit can be used to take out contact...