This circuit was obtained from HAM Radio magazine in an 80's issue. The FETs are types of the time and the frequency is determined by the crystal. The circuit operates at voltages from 3 to 9 V.
Like the previous circuit, this is used in the analog part of the telephone lines. The same...
This analog TV circuit generates bars in the NTSC standard. We found it in the July 1991 issue of...
This transmitter kicks in when the microphone picks up sound. This sound then modulates the signal...