This circuit can be used with 3 receivers and is intended for low frequencies (medium wave range). We found it in the September 1995 Electronics Now magazine.
Using NTCs or LDRs as sensors, the frequency of this circuit depends on the temperature or the...
This circuit was found in a Popular Electronics from 1991. The transistor could be the BC548. The...
This circuit was found in a 1994 publication. It can receive signals from the 3 to 20 MHz band,...