Micro Power AM Receiver

Micro Power AM Receiver Circuit diagram This is basically a crystal radio with an audio amplifier which is fairly sensitive and receives several strong stations in the Los Angeles area with a minimal 15 foot antenna. Longer antennas will provide Continue reading

Simple AM Transmitter

Simple AM Transmitter Circuit diagram: Circuit Description There are not many AM transmitters that are easier to build than this one because the inductor is not tapped and has a single winding. There is no need to wind the inductor Continue reading

Magnetic-Radiation Remote-Control

Magnetic-Radiation Remote-Control Short-range 35KHz operation, single-channel unit Simple circuitry, no outer antennas required Transmitter circuit diagram: Transmitter parts: R1 68K 1/4W Resistor C1 4n7 630V Ceramic or Polyester Capacitor C2 60-80pF 63V Ceramic Trimmer C3 100µF 25V Electrolytic Capacitor Q1 Continue reading

Simple Short-Wave Transmitter

Simple Short-Wave Transmitter Circuit Description This low-cost short-wave transmitter is tunable from 10 to 15 MHz with the help of ½J gang condenser VC1, which determines the carrier frequency of the transmitter in conjunction with inductor L1. The frequency trimming Continue reading

Simple Op-Amp Radio

Simple Op-Amp Radio Circuit diagram This is basically a crystal radio with an audio amplifier which is fairly sensitive and receives several strong stations in the Los Angeles area with a minimal 15 foot antenna. Longer antennas will provide a Continue reading

Small Radio Transmitter

Small Radio Transmitter Circuit diagram Circuit Description Contains information about building a small radio transmitter, which has a PCB 1.75″ x 2.5″ (45mm x 68 mm) and has a range of about 30 yards or so. The documentation with the Continue reading