This small FM spy transmitter uses three transistors with an RF amplification stage. We found it in an Australian publication from 1991.
This circuit was published in a 1981 magazine, but it can be easily assembled, as all components are...
The purpose of this circuit is to increase the power and range of a small walkie talkie. The...
This fourth-order circuit was found on an 80's Radio Electronics. The power supply must be...