Category Archives: Radio

FETs based Micro-Spy

This is Micro-Spy circuit which designed using FET components.. Circuit Notes:

This is probably become the simplest radio frequency RF transmitter that you will find anywhere. It has a total of five parts and can be constructed into a very small space. It is great for science fair projects or other science related projects where short range transmission is useful. It operates on 1.5 to 3… Read More »

Very Simple Radio Control (R/C)

Above diagram is a very easy and efficient receiver for actuating garage doors, starter motors, alarms, warning systems and many some other possibilities. The SCR, which has a extremely low trigger current of 30 uA is typical — it demands an input electricity of just 30 uW to activate the relay. A high Q tuned… Read More »

FM Receiver Antenna Amplifier

This is the active FM receiver antenna amplifier, used to boost the FM signal catch by the antenna, you may call circuit “FM antenna booster”. By working with only a small handfull of parts you can assembled this kind of reliable FM amplifier circuit. It runs with only 1 UHF/VHF type transistor, MFE201. This amplifier… Read More »

Mini MW Transmitter

The following is a circuit of a simple AM transmitter. This circuit is available in kit form and can work well since the kit available on market. This circuit uses a combination of transistors SA101 and SA103, as the modulation signal amplifier.

250mW RF Power Amplifier

This is an 250mW RF power amplifier circuit project. This circuit is designed to amplify the output of about 7mW wide band FM transmitters to a final level of about 250mW. General purpose 12V DC power supply can be used to operate this RF amplifier circuit. Schematic Diagram: Components List: R1 ____________________ 10R R2 ____________________… Read More »

One Transistor FM Receiver

This is a very simple FM receiver which build based on one transistor only. No chip or another active component. The output is connected to earphones, you need an amplifier circuit if you want to listen the radio with a loudspeaker.

FM Receiver with TDA7021T

This is the circuit diagram of mini FM receiver that build based on single FM IC TDA7012T. Components List: R1 = 8kΩ2 R2 = 10kΩ R3 = 390Ω C1,C3 = 10nF C2,C6,C9,C16 = 100nF C4 = 33pF C5 = 25pF trimmer (Murata type TZB4Z250AB10R00) C7,C10 = 1nF5 C8 = 820pF C11 = 1nF C12 =… Read More »

One Chip AM Radio Receiver

Here is the AM Radio receiver circuit diagram based on old single IC MK484. Components List: R9, R10_________ 6R8 R6_____________ 100R R3_____________ 1K R1_____________ 4K7 R7_____________ 5K6 R4_____________ 10K R2_____________ 100K R5_____________ 150K R8_____________ 820K Pot_____________ 10K log pot Coil & ferrite bar set C7______________ 470p ceramic C, C4, C5, C6_____ 470nF monoblock C2______________ 100nF… Read More »