The following diagram is the schematic diagram of Ni-CAD battery charger circuit which featured with current and voltage limiting to keep the battery lifetime. The lamp L1 will be light brightly and the LED will be out when the battery is low and battery charging in progress, but the LED is very bright and the… Read More »
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 »
Below circuit is an echo chamber circuit which can be used for smoothing your voice from the microphone. This circuit may used for any kind of audio signal (microphone, radio, mp3 player, etc). The echo chamber circuit is great for human voice (karaoke), i doesn’t needed for music sound. This circuit is quite complex with… Read More »
This is the sound generator which will simulate British police car siren. The circuit is built using 2 pieces of timer IC 555 to generate sound frequency. How the circuit work:
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 »
Here is the circuit diagram of active DC voltage doubler which used to increase the DC voltage. This circuit drives relays of 24 and 18VDC from a 12V power supply. Use this circuit can be work with almost any PNP or NPN power transistor, of course the transistor with specific characteristic similar to the transistor… Read More »
This is the circuit diagram of emergency light included the alarm circuit to show you that there is no power source in your building due to shutted down or short circuit. When the electric in your home/company has been shutted down for maintenance and or shutted down due to short circuit, you may need this… Read More »
This is the circuit diagram of dancing LEDs which consists of 10 units LEDs. The 10 dancing LEDs circuit works like a audio level meter. The LEDs will be dance sequence with the sound level that entering the microphone. Components list: R1_____________10K 1/4W Resistor R2,R3__________47K 1/4W Resistors R4______________1K 1/4W Resistor R5,R6,R7______100K 1/4W Resistors R8____________820R 1/4W… Read More »
The following diagram is the basic design diagram of inverter circuit. The circuit will convert 12V DC to 120V AC. This basic inverter circuit can handle up to 1000Watts supply depends the T1, T2 and transformer used. Please see the note. Basic Inverter Components list: Part Total Qty. Description Substitutions C1, C2 2 68 uf,… Read More »