Small FM Radio Circuit
by D Mohankumar in Radio |
Perhaps this is one of the simplest and smallest FM radio receiver that can receive the FM stations available locally. Its simple design makes it ideal for a pocket sized FM receiver. The output of the receiver drives a head phone. The circuit works off a small 4.5 volt battery or two 3.6 volt Lithium button cells. The fm...
27MHz CB Receiver Circuit
by Received by Email in Radio |
This is a simple 27MHz FM-CB receiver circuit built with TCA440 for listening CB ( citizen’s band ) transmissions with FM (frequency modulation). The selection is made with ceramic filters. This 27 MHz receiver works with an intermediary frequency of 455 kHz. The input filter is 27 MF type, so we obtain an acceptable attenuation of the mirroring frequency....
PC FM Radio Circuit
by P. Marian in Radio |
This is a fm radio receiver circuit which can be used with PC. PC radio REGULATIONS A) With the P1 we regulate the intensity of sound. B) With the P2 we regulate the frequency of reception. C) Optionally: If you want to check the frequency with your PC it will be supposed you make the following energies: – You...
LM386 Audio Amplifier Circuit
by Received by Email in Audio |
The integrated chip LM386 is a low power audio frequency amplifier requiring a low level power supply (most often batteries). It comes in an 8-pin mini-DIP package. The IC is designed to deliver a voltage amplification of 20 without external add-on parts. But this voltage gain can be raised up to 200 (Vu = 200) by adding external parts....
by P. Marian in Datasheets |
LM386 is a power amplifier designed for use in low voltage consumer applications. The gain is internally set to 20 to keep external part count low, but the addition of an external resistor and capacitor between pins 1 and 8 will increase the gain to any value from 20 to 200. The inputs are ground referenced while the output...
by P. Marian in DIY |
In this intercom schematic, the 8 ohm speakers is used as microphone and listening speaker. The 10K potentiometer controls volume and the total gain can be set with de 5k R. Use a double switch with 2 positions so when one is used to talk and the other one to listen. The switch will be in the house. Intercom...
Electronic Siren with Multitone
by P. Marian in Audio |
This multitone electronic siren is useful for burglar alarms, reverse horns, etc. It produces five different audio tones and is much more earcatching than a single-tone siren. The circuit is built around popular CMOS oscillator-cum-divider IC 4060 and small audio amplifier LM386. IC 4060 is used as the multitone generator. A 100μH inductor is used at the input of...
IR Infrared Detector Circuit
by P. Marian in DIY | Measure |
This infrared detector can be used to detect the presence of modulated infrared signals in its vicinity from any electronic source, for instance, an IR handheld remote controller. It can also be used for testing infrared burglar alarm systems. This is not an infrared motion detector! The IR detector circuit in principle, converts the IR signal pulse trains into...
LM386 Amplifier Circuit
by P. Marian in Audio |
myCarAmplifiers.com published a new article with LM386 amp circuits designs. There are 4 LM386 audio amplifier circuit designs, with gains of 20, 50, 200 dB and a bass boost circuit. LM386 is a versatile, small power amplifier designed for use in low voltage consumer applications. The gain is internally set to 20 to keep external part count low, but...