Switch-mode driven 1.5V bulb, Portable unit – 3V battery supply This device was designed on request; to control the light intensity of four filament lamps (i.e. a ring illuminator) powered by two AA or AAA batteries, for close-up pictures with a digital camera. Obviously it can be used in other ways, at anyone’s will.IC1 generates [...]
Digital Clock and Temperature This is a digital clock and temperature display which is alernate display between time and temperature. Feature – Display time 24-hour format. 00:00 – 23:00 – Use DS1307 RTC with 3V betterry back-up. – 1 channel temperature sensor(DS1820) – measures temperatures from -55 to + 125 degree Celsius. – Temperature accuracy [...]
The circuit below illustrates two pairs of LEDs that operate out of phase so as one pair slowly illuminate, the other pair will fade. Circuit description: This circuit is used to slowly illuminate and fade a pair of red LEDs (light emitting diodes). The fading LEDs could be installed as ‘eyes’ in a small pumpkin [...]
This circuit consists of two identical intercom units. Each unit contains a power supply, microphone preamplifier, audio amplifier and a Push To Talk (PTT) relay circuit. Only 2 wires are required to connect the units together. Due to the low output impedance of the mic preamp, screened cable is not necessary and ordinary 2 core [...]
Suitable for operating, Lamps, Fan, Radio etc.., Small n easy unit Here is the circuit diagram of Remote Operated Home Appliances or Remote controlled Home appliances. Connect this circuit to any of your home appliances (lamp, fan, radio, etc) to make the appliance turn on/off from a TV, VCD, VCR, Air Conditioner or DVD remote [...]
Recently, I had to design a circuit real quick that transmitted 4 parallel TTL data bits over 350m of twisted pair cable. I needed to feed in four parallel data bits at one end, and get 4 parallel data bits out the other end, completely transparent to the transmitting and receiving circuits. I decided to [...]
This circuit is an oxygen sensor for car. The oxygen sensor simulator as built on a protoboard. Note the cigarette lighter plug used for power source. The adjustment knob is at the left, and the switch is on the right. The red indicator LED is in the middle. Only use red, because the voltage drop [...]
