Recent content by rahulb

  1. R

    finding 4 pin connectors for own wires

    I need such connectors but without wires. Unfortunately, they are coming with wire attached
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    finding 4 pin connectors for own wires

    Hi Everyone, I am searching for 4 pin connectors both male and female to which I can add my own wires. There are jst connectors available but they already come with attached wires. Is there any such connector available. Power supply rating 12v 5 amp. thanks
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    Help me in calculating base resistance for transistor

    no, I chose 330 ohm for green and yellow, 390 ohm for red. 180 ohm was due to some wrong calculation earlier. sorry.
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    Help me in calculating base resistance for transistor

    I have calculated resistor values using 2.1 v as forward voltage for green and yellow leds and 2 v for red leds. Also, the current flowing to leds will be 10 mA. About the mosfet, I am thinking to use stp55nf06 mosfet as it is easily available for me. I hope this is a good choice for this...
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    Help me in calculating base resistance for transistor

    sorry for the mistake. I am using red, green and yellow 5mm leds. one color for each of the three outputs. I checked the forward voltage of green because I have the confusion about it. It comes around 2.1 to 2.2 volts. thanks
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    Help me in calculating base resistance for transistor

    actually I need to connect a lot of leds. thats why I am using transistor. 4 leds in series and 34 such series in parallel. So, if one series consumes 10 mA then 34 series will have almost 340 mA. The resistor 180 ohm I chose for 4 led in series. So, you are telling that base current should...
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    Help me in calculating base resistance for transistor

    please tell me if my resistor value of 2.2 k to the base is fine or I have to change it
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    Help me in calculating base resistance for transistor

    hi, what should be the value for bypass capacitor?
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    Help me in calculating base resistance for transistor

    no, actually the 4017 chip no. is HCF4017, I could found it in eagle so added that one.
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    Help me in calculating base resistance for transistor

    the supply bypass capacitor on pin 3 of timer 555?
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    Help me in calculating base resistance for transistor

    Hi, I am making a circuit for a led chaser. the leds should glow one by one. I am testing the circuit with one led for each transistor later I will add array of leds to each transistor. I want the base resistor value to make the transistor turn on. Leds will have resistors to limit current...
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    Confusion about led's forward voltage

    Hi, I have confusion about the forward voltage of leds. Do the colored diffused dome type of leds have same forward voltage as the clear dome type? e.g. Blue colored diffused dome type led will have same voltage as the clear dome type? colored diffused dome type Clear dome type thanks
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    Strange voltage variation in circuit

    Hi, I made a circuit which turns on according to sounds. actually it toggles. One loud sound, it turns on and in the next, it turns off. When I measure voltage across the electret. it is around 6 v. I am using 9 volt battery for power which is producing around 8.5 volts. Now the problem is...
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    Does the TDA2030 need negative potential?

    The problem with Class D amplifiers is, they come in surface mount package whereas I need a through hole package that I can solder with soldering iron. I don't have a blowing gun.
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    Does the TDA2030 need negative potential?

    I need atleast 5 W of power
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