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Need Help with LEDs

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ANTlabs

New Member
I have only been doing electronics for a year now and am new to this site. I need some help with a circuit I am putting in my Halloween costume this year.Please help me fill in some blanks for me. I need a circuit in which there are four push buttons, one leading to each of the fowloing: one button activates a white LED, a second one activates a circuit that makes 15 green LEDs fade in and out, another push button activates 4 red LEDs that also fade in and out, the final button activates a sound recording. Can someon please deveop a circuit and give me the schematic? I also have these questions:


1. will green and red LEDs shine through a thin black cloth?

2. How do you make a small voice recorder?

3. How much in-put voltage will the circuit need?

4. Is there anything the circuit is missing?

5. How much is this going to cost me!?!?


Any suggestions are welcome.
 
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audioguru

Well-Known Member
Most Helpful Member
I also have these questions:

1. will green and red LEDs shine through a thin black cloth?
I don't know. try it and see.

2. How do you make a small voice recorder?
Buy one in the sale the day after Halloween.

3. How much in-put voltage will the circuit need?

4. Is there anything the circuit is missing?

5. How much is this going to cost me!?!?
Look and see.
 
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ANTlabs

New Member
I can't get a recorder the day after halloween because I need it for halloween.

Also I said I was very new to electronics and don't know how much power any circuit takes unless the schematic specifies it and I dont even know how to build the circuit. Let alone how much parts cost.
 

audioguru

Well-Known Member
Most Helpful Member
The day after last Halloween I saw for sale exactly what you want for $2.00 each.
A Chinese company made millions of them.

You can design and make one if you want.
 

audioguru

Well-Known Member
Most Helpful Member
I have never designed nor looked at a cheap Chinese Halloween toy.
 

audioguru

Well-Known Member
Most Helpful Member
Unless they are extremely dim, lEDs use power.
Unless you have a huge and heavy car battery, a little battery does not have much power so it will not last long driving 15 LEDs.
 

audioguru

Well-Known Member
Most Helpful Member
Half an hour is such a long time that you will not see the LEDs fade and brighten.
 

colin55

Well-Known Member
This circuit will fade the LED and gradually illuminate it:
9025-FadingLED.gif
 

ke5frf

New Member
That would be a Schmitt Trigger... helps with hysterisis.
Looks like the output is inverted, judging by the notation at pin 2.
The symbol inside means "hysterisis".
 
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audioguru

Well-Known Member
Most Helpful Member
The triangle with the positive supply pin not shown and the hysteresis symbol inside is 1/6th of a hex Schmitt-trigger Cmos logic inverter IC called the 74C14. It makes a square-wave oscillator as shown with only one single feedback resistor and one timing capacitor.
 
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