IR receiver oscillates if powered by rectified source. help?

folarinv said:

I constructed an infra-red receiver using IR-sensor from TV, schmitt trigger-4093, monostable-555, flip-flop:4013, transistor and relay. I'm using this receiver to switch on/off a lamp. The problem with the circuit is that if i power it with a rectified voltage source, the lamp will start going on/off by itself (oscillation) but if i power it from a 9V battery source, the circuit behaves properly.

How can I modify the circuit so that I can power it with a rectified voltage source as the 9V battery gets drained within minutes.

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Nigel Goodwin said:

folarinv said:

I constructed an infra-red receiver using IR-sensor from TV, schmitt trigger-4093, monostable-555, flip-flop:4013, transistor and relay. I'm using this receiver to switch on/off a lamp. The problem with the circuit is that if i power it with a rectified voltage source, the lamp will start going on/off by itself (oscillation) but if i power it from a 9V battery source, the circuit behaves properly.

How can I modify the circuit so that I can power it with a rectified voltage source as the 9V battery gets drained within minutes.

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If you mean a three pin IR receiver IC?, these need seperate supply decoupling, feed the IC power through a resistor with a decoupling capacitor - check my IR PIC tutorials for details of suitable values.

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folarinv said:

Nigel Goodwin said:

Nigel, I'm not clear with your suggestions when u said i should decouple the power supply to the 3-pin IR receiver. Secondly, your PIC tutorial site talks about programming. I couldn't find much help there

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Look at the hardware pages for my tutorials, the one for the IR tutorial shows how to connect IR receivers - the exact page is . It uses a 47 ohm resistor and a 47uF capacitor, these decoupling components are VITAL!.

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I used a 9V regulated power supply taken from an hobbyist kit but it did not stop the oscillation.

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Nigel Goodwin said:

folarinv said:

Nigel Goodwin said:

Nigel, I'm not clear with your suggestions when u said i should decouple the power supply to the 3-pin IR receiver. Secondly, your PIC tutorial site talks about programming. I couldn't find much help there

Click to expand...

Look at the hardware pages for my tutorials, the one for the IR tutorial shows how to connect IR receivers - the exact page is resistor and a 47uF capacitor, these decoupling components are VITAL!.

Click to expand...

Thanks Nigel.

The circuit seems to be stable now. I've been testing it for over 48hrs and
it has not make any unsolicited switching.I used a 470resistor and 47uf capacitor for a 9V power supply. I just hope it remain stable forever.

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folarinv said:

The circuit seems to be stable now. I've been testing it for over 48hrs and
it has not make any unsolicited switching.I used a 470resistor and 47uf capacitor for a 9V power supply. I just hope it remain stable forever.

Click to expand...