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 [...]
Time Interval Relay Circuit for the clock circuit above This is a programmable clock timer circuit that uses individual LEDs to indicate hours and minutes. 12 LEDs can be arranged in a circle to represent the 12 hours of a clock face and an additional 12 LEDs can be arranged in an outer circle to [...]
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 [...]
88-108 MHz FM Beacon Broadcast Transmitter Circuit This circuit will transmit a continuous audio tone on the FM broadcast band (88-108 MHz) which could used for remote control or security purposes. Circuit draws about 30 mA from a 6-9 volt battery and can be received to about 100 yards. A 555 timer is used to [...]
20VAC 60 Watt Sunrise Lamp Circuit In this circuit, a 120VAC lamp is slowly illuminated over a approximate 20 minute period. The bridge rectifier supplies 120 DC to the MOSFET and 60 watt lamp. A 6.2K, 5 watt resistor and zener diode is used to drop the voltage to 12 volts DC for the circuit [...]
This is a similar circuit to the above and provides a 4 LED bar graph indicating the voltage of a common 3.6 volt Lithium – Ion recharable cell phone battery. The reference voltage is provided by a TL431 programmable voltage source which is set to 3.9 volts where the TL431 connects to the 1K resistor. [...]
This array charger ambit is advised for recharging NiCad batteries based on an AC-powered accepted antecedent method. It can crank out as abundant as 1 amp and can be adapted to go alike college by allotment altered accessories for Q1. Since this ambit uses AC band voltages and currents, amuse exercise acute attention during assembly, [...]
