RF or even switching transistors like the 2N2222 can be used in this circuit. The capacitors are ceramic and the frequency is determined by the crystal.
The voltage gain of this DC amplifier is 100 times, given by the relationship between R2 and R1....
Here is a very useful circuit suggested by ICOTRON (Siemens) capable of eliminating the...
This circuit, suggested by Texas Instruments, is based on the integrated TL497A, designed for...