The following image is the scheme diagram of six LED stereo VU display circuit which build using Dot/Bar Display Driver IC LM3915. This VU display should be connected before amplifier module circuit. You may connect this circuit at pre-amp output, tone control input/output or equaliser input/output. This circuit powered with 12V DC supply. About LM3915:… Read More »
Here is the USB sound card circuit based on PCM2706 which dedicated for USB audio. With USB controller module inside PCM2706, there is no more additional programming to the IC. The computer system will automatically detect this circuit when connected to the USB port. You will get stereo audio channel output from this circuit. Schematic… Read More »
This is an audio mixer circuit which designed along with VU meter circuit. The circuit is for one channel input, if you need, for example 5 channel mixer, then you need to build 5 similar circuits. The this audio mixer uses three potensiometers to adjust volume level, low frequency (bass) level and high frequency (treble)… Read More »
The following diagram is the circuit diagram of 20 band stereo graphic equaliser which will controlling the audio signal in specific frequency range. The power supply used for this circuit is symmetrical (dual polarity) type, 15V DC.
This simple 220V light dimmer circuit can be used to adjust the brightness of mains lights. It also can be used to adjust the speed of AC motors. It uses a triac, diac and has a radio-frequency interference (RFI) noise suppression circuit built into it as well. Schematic diagram: Components List: R1 = 10K R2… Read More »
This is a 220V LED flasher circuit which is intended as a reliable replacement to thermally-activated switches used for Christmas tree lamp-flashing. This a low cost circuit and easy to built since it only use little amount of electronic components.. Schematic diagram: Component Parts: R1_________ 100K R2,R5______ 1K R3,R6______ 470R R4_________ 12K C1_________ 1000uF 25V… Read More »
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.
This circuit is a powerful three stage, 9V FM transmitter (Tx) with a range of up to 1 kilometer in the open. It uses an RF transistor in its output stage and two BC547″s for the first two stages. Distance of trans-mission is critically dependent on the operating Conditions (in a building or out on… Read More »
This is the circuit diagram of UHF band TV antenna booster with 15dB gain power. This low cost antenna booster is simple and easy to build.It use single transistor BF180 to boost te UHF signal. Since this is an active circuit of UHF TV antenna booster, it will require a 12v power supply to operate.… Read More »