This transmitter emits a modulated signal at a frequency given by the first transistor in the phase shift oscillator. The circuit is from an Australian publication from 1991.
Found in a 90s Popular Electronics, this circuit is interspersed between the filter and the...
This circuit is from an 80's documentation. The integrated circuit is from the time and the...
This circuit was found in a 80s American documentation. The zener diodes determine the points of...