This oscillator version is from an RCA documentation from the 1970s. Transistors support modern equivalents and the power can be supplied in a voltage range of 5 to 12 V. For Q2 we suggest the BD136.
This alarm circuit was found in a 1982 publication. It uses components that can still be found...
The circuit of this power supply was obtained in an American publication of 1982. We changed some...
This circuit was found in Texas Instruments documentation from the 1980s. The circuit has a Q less...