These units can be useful as a short-range, single-channel remote-control. When the pushbutton in the transmitter circuit is briefly activat...

The circuit for a powerful AM transmitter using ceramic resonator/filter of 3.587 MHz is presented here. Resonators/filters of other freq...

Here is a circuit of a remote control unit which makes use of the radio frequency signals to control various electrical appliances. This r...

An low power FM Transmitter using an op-amp as the audio preamp and a single transistor as the RF amplifier. L1 is 0.112uH (this tunes to th...

Using the circuit of 40-metre band direct-conversion receiver descr- ibed here, one can listen to amateur radio QSO signals in CW as well ...