This intermediate frequency amplifier step using 2 junction FETs has a gain of 20 dB. The pass band is 4 MHz. FETs are for general use, with several types that serve in this circuit as BF245.
Using power transistors of the time, this source was published in Radio Electronics magazine in...
The network formed by resistors and capacitors determines the frequency of this sinusoidal...
The sensor in this circuit is an LDR and the potentiometer serves to control the sensitivity...