Maintain idling car battery in fully charged condition

It is essential to maintain car battery in full charging condition lying idle for long periods. It often so happens that while the car is attempted for a start it fails to do so. Usually battery capacity falls in unused cars for some small gadgets like remote etc still drawing little power besides bit self discharge of the inherent features of lead acid batteries traditionally fixed in cars. Submitted below a very few low cost DIY tickle charger, as commercial ones are quite expensive. Option1&2 as explained below= Rs 400/-(excluding the power bank ). Option 3= Rs 300/- If your car is parked outdoors with some little chance of sunlight ( even shaded)  falling on the car, then the best option is to use any available  solar cell phone  power bank of around 10,000mAH  along with procured a dc to…

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Voltage Stabilizer for very low ac input

This circuit describes AC voltage stabilizer ,/ automatic voltage regulator function  with its input voltage range from AC 120 to 260V, at output voltage of AC 220 ( 1 ± 10%) V, Output power for this can be 300-1000W depending upon the transformer used. Working:- AC voltage regulator circuit forms the power circuit with transformer and the voltage detection control circuit , as shown in Figure above . Voltage sensing circuit consists of four operational amplifiers formed out of an integrated circuit IC (Nl-N4),operating in comparator mode. Resistor, R7, capacitors C4, a potentiometer P, relay Kl-K4, are other sections of the circuit. . R7, RP, VD5, VD6 with C4 are for input voltage sensing circuit. Power supply for the circuit consists of series capacitor Cl, C2, resistor Rl, a bridge rectifier diode VDl-VD4, a  filter capacitor C3,a zennor regulator diode…

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DIY Voltage Stabilizer for ac utility

It is often seen that our mains utility power supply fluctuates to a large extent from the specified range. Presented below a DIY “do it yourself” voltage stabilizer for 230 utility with readymade electronics cards. All that one has to do is to get the transformer made as per the data are given in the table and then get a suitable enclosure to house all the items to give it a finished look. Input AC Voltage range of 140V to 280V AC. Regulated output voltage to ensure voltage in range 200 -245 VAC.Voltage correction within 10-20 mSec. Relay operation near zero crossings of current to ensure reliability and fault-free operation. Intelligent Output Time Delay for protection of load connected. Mains under voltage and over voltage cut off to protect the connected load. ( U/V – <175V , O/V > 250V)…

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