Radio circuit diagrams electronics projects for radio transmitter, radio receiver circuit, rf amplifiers, rf boosters and some other related RF circuits like: fm antenna booster, microwave transmitter and wireless modules.
The TDA7021T is a integrated radio receiver circuit for portable radio ( stereo or mono ) and is fully compatible for applications using the low-voltage micro tuning system (MTS).
This car tracking device circuit can be used to locate car in a parking or other objects and is made up of two parts. The first part of this car tracking device circuit is an RF oscillator based on Lm555 timer and the second part is a sensitive receiver .
To find the object using this car tracking device circuit is use a visual indications with 5 LEDs which indicate the signal strength.
This lighting detector circuit it's in fact an receiver tuned to 300 kHz designed to detect the crackle of approaching lightning. A bright lamp flashes in synchrony with the lightning bolts indicating the proximity and intensity of the storm.
The flasher is biased to not flash until a burst of RF energy, amplified by the 2N3904, is applied to the base of the 2N4403. The receiver standby current is about 350 microampers.
To increase sensitivity of this storm detector you must use a longer antenna.