Radio electronic circuits

This circuit may be tuned to operate over the range 87-108MHz with a range of 20 or 30 metres. ... [read]

A compact 2 transistor transmitter for use at VHF frequencies... [read]

This is the schematic for an FM transmitter with 3 to 3.5 W output power that can be used between 90 and 110 MHz. Although the stability isn't so bad, a PLL... [read]

The input can be from a longwire or a loop antenna. The unit covers MW and Sw to 30MHz. ... [read]

This circuit provides an FM modulated signal with an output power of around 500mW... [read]

Very strong FM transmitter. You maybe need license to run this.... [read]

It uses one, six foot square, six turn loop, and is aperiodic in nature, covering the frequency range 50KHz - 5000KHz... [read]

This circuit is a 73 MHz Hallogene Lamp Radio-Controlled. The purpose of it is to control the power state of a hallogene lamp by a remote control.... [read]

Contrary to what some radio experimenters think, a bipolar regenerative design can be made to work efficiently... [read]

This SMD FM transmitter has an operating frequency of about 80 to 115MHz. Under reasonable circumstances you will be able to receive its signal at a distance... [read]

AM FM Simultaneous Transmitter Using Digital IC ... [read]

This is a compact three transistor, regenerative receiver with fixed feedback. It is similar in principle to the ZN414 radio IC which is now replaced by the... [read]

The circuit is in two halfs, an audio amplifier and an RF oscillator.... [read]

CB receiver... [read]

Frequency of emission at AM: ~27MHz... [read]

This is a wide band signal strength meter circuit which responds to small changes in RF energy, designed to be used for the VHF spectrum and will respond to... [read]

FM transmitter with OpAmp circuits... [read]

Frequency of reception: 88~108MHz... [read]

This small transmitter uses a hartley type oscillator. Normally the capacitor in the tank circuit would connect at the base of the transistor, but at VHF the... [read]

This small FM transmitter circuit by David Sayles... [read]

A small FM voice transmitter for Band 2 VHF ... [read]

A amplifier of force RF for the FM, is always essential for the amateur that wants it strengthens some small transmitter, that likely already it has manufactured... [read]

This is a medium range transmitter circuit diagram. This is also improved by changing the values of the resistor.... [read]

This circuit is designed to amplify the input from a telescopic whip antenna... [read]

Simple radio with operational amplifier circuit diagram.... [read]

The circuit for a powerful AM transmitter. The range of the transmitter is expected to be one to two kilometers.... [read]

This Field Strength Meter is simple and also quite sensitive. It uses an ordinary digital voltmeter to measure RF signal strength up to a few hundred MHz... [read]

The circuit is (of course) only mono, and accepts an audio input from either a microphone or other source. The input impedance is 1Mohm. The input sensitivity... [read]

This circuit can be used to "sweep" an area or room and will indicate if a surveillance device is operative... [read]

A Short Wave Receiver based on the MK484 (formerly ZN414) that includes the tropical bands and 49 metre bands... [read]

The ATL-3 Loop Antenna. The Medium Wave Circle can be found on http://www.mwc.org... [read]

Force of expense: max 45W... [read]

A VHF band TV transmitter using negative sound modulation and PAL video modulation. This is suitable for countries using TV systems B and G.... [read]

This circuit is designed to work at UHF frequencies in the range 450-800MHz. It has a gain of around 10dB and is suitable for boosting weak TV signals.... [read]

An AM portable radio receiver made from the ZN414 IC. The ZN414 ic has now been replaced by the MK484 which is identical in performance and pinout. ... [read]