This circuit was found in the December 1992 Radio Electronis magazine. R2 is an NTC, there is a MOV protector or NTC thermistor. The current depends on the thermistor used.
This conventional astable uses two NPN transistor and was found in a publication of the year 1968. The...
This simple effect circuit for musical instruments and stereos was found in a 1987 publication. Powered by...
This circuit is a suggestion from a Radio Electronics from October 1964. We found it in the patent...