Hobby Electronics
Knowledge improvement test on IC 555
This test on IC 555 will give you good idea about its basic working. First to improve your knowledge, you are suggested to read following posts… All about IC 555 How IC 555 can be used as MMV? IC 555 as Astable multivibrator Tricky situations in IC 555 Frequently Asked Questions about IC 555 Online [...]
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Indoor and cool white light source for your car
When you purchase a new car or even an old one, the indoor light is generally a simple incandescent lamp giving off pale yellow light. In this light, you cannot read anything inside the car, nor there is enough pleasant atmosphere inside the car, when such light is lit.
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The tricky situation in the working of IC 555, a practical absurdity of IC 555
Many a times I wonder that how the IC 555 works differently. Is it its manufacturing fault? Or the internal circuit problem? Or the basic designing problem, itself?
The question is, what exactly the point, am I driving at?
Well, if you are an electronics hobbyist, you will agree the facts which I am now presenting here.
Suppose we build one circuit of astable multivibrator using IC 555. The values of R1, R2 and the timing capacitor C are as such that the output frequency of the circuit is roughly around, say 1kHz.
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Internal structure of permanent magnet moving coil meter (PMMC)
The basic constructional diagram of the meter is given here. In this meter, a permanent magnet is used known as horseshoe magnet. Between the two poles of this magnet, a coil is suspended. This coil is wound on paper cylinder and its two terminals are taken out for external connection.
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How to use a speaker as a microphone? Speaker can be used as a microphone.
If you observe the constructional details of a speaker you will see that it contains one coil suspended between two permanent magnets. The terminals of the coil are connected to high power audio output of an amplifier, so that current flows through this coil and an alternating magnetic field is produced around it.
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How does an LPG gas geyser work?
Be aware of false working This is the water flow sensor, which contains one SRC DEV inductive sensor fitted on a brass tube, as shown in this photo. When the hot water tap is open, water flows through this tube, it moves one magnet inside the tube below this sensor. Due to motion of this [...]
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Simple methods for transistor testing
Refer article to test the transistor and diode to find their terminals. We can also identify the terminals as follows… In a bipolar transistor, each “PN” junction is essentially a diode. Consequently, you can use a multimeter to test each pair of pins of the device (with the third pin left floating in each test) [...]
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Monostable multivibrator using IC555: a novel circuit idea
Though it is a one shot multivibrator it may absorb some external noise from outside or nearby source, and may produce false triggering. This drawback is a COMMON DRAWBACK in IC555. Generally the hobbyist tries to connect one 0.01uF capacitor to control voltage pin-5 of the IC w.r.t. ground. But this does not give full protection against noise and may trigger the IC giving false alarm.
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How to do nulling of input offset voltage in Operational Amplifier?
The input offset voltage of operational amplifiers (op amps) arises from unavoidable mismatches in the differential input stage of the op-amp circuit caused by mismatched transistor pairs, collector currents, current-gain betas(b), collector or emitter resistors, etc.
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Useful tips and tricks for electronics hobbyists
How to get flicker-free fluorescent starting of fluorescent tube lights? Actually the fluorescent tubelights are now rarely used. But by chance, if you do have a one like this, then it is better for you to read this topic. Here there is an extremely simple but very effective modification which will eliminate the flickering when [...]
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