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  1. H

    Infrared Activated Switch

    Hi audioguru, The thing is, it was somewhat difficult to get my hands on a phototransistor, yet enough, get a photodiode. But ill try. I was looking through the datasheet of the NE567 and showed my how to calculate the center freqency. But it doesn't mention what unit to use for the...
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    Infrared Activated Switch

    Never mind about the detection bandwith as you already answered it before. Silly me, i forgot all about it. Thanks ;D
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    Infrared Activated Switch

    Hi audioguru, Say i add the 100K resistor to the op-amp, and i reduce the freqency to say 200Hz (or what ever the photo transistor can detect - SFH300), and i get a 741 op-amp, will it work then? Regarding the AGC, i dont need that. I actually dont want it. And since ill be setting the center...
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    Infrared Activated Switch

    Hi audioguru, Im having alot of trouble from the IR receiver module. Dont bother to ask why. After my first one got fried (which was perfect), ive been having alot of trouble. I couldnt get the exact same one and thus am having trouble with the new ones (As i mentioned before). So what i have...
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    key chain laser power supply

    Im just saying what i read. BTW, the laser beam doesn't stay focused in long range. the beam becomes wider and wider as distance increases. Even if your in the sky, light will reach you. Especially if its focused like the laser. And the beam fills the cockpit window (i think) with red light. Not...
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    LED questions

    IR emitter = IR LED The reason TV remotes have great range is because the signal (form the remote) is sent in bursts (i.e. 10 bursts a second) meaning you can allow more current to pass through the LED --> strong signal. You see, LED's are rated i.e. 30mA max at continous current. If you...
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    50.000V Powersuply

    Whats your project about? Maybe you mis spelt or calculated the values.
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    Transistor Biasing Problem

    Wa'Alaikum Alsalam, Did you draw the schematic (circuit) yourself or did you get it from somewhere? From what im seeing, the arrangement doesn't look 100% correct. I see that you're using a PNP transistor, which means you need negative supply (or 0 as you'll read at the end) at the base...
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    50.000V Powersuply

    Hmm, your right!!! I guess I'll have to teach my physics teachers whos "teacher". Cheers mate ;)
  10. H

    key chain laser power supply

    Hey, I made a project similar to yours but the problem is that i got told of from my parants for using a laser beam. Old folks, what to do! So i switched to Infrared which is much more complicated (as you can see from the "Infrared Activated Switch" topic). It worked like a charm. But i hade...
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    Homemade Capacitor

    Cool Stuff Dude!!! BTW, can i use normal alaminium foil (kitchen foil)? ;D
  12. H

    50.000V Powersuply

    That means your mains can supply a max of 32 x 220 = 7040W which is a lot smaller than what you need. Remember: Power Out (50,000W) = Power In 50,000 < 7040 (which is not true) --> you'll probably blow up your mains supply. Fuses cannot be arranged in a parallel setup. Im not really sure...
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    Infrared Activated Switch

    Hi audioguru, I found out the problem for the 555 timer overheating. I was looking at the datasheet (of the 555) and it said R1 and R2 should be between 1K and 1M. Before i was using, R1 and R2 which added up to 147 Ohm which is way too small. So i changed the components to still give 56KHz...
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    50.000V Powersuply

    I agree, 50KW (50,000W) is alot of power. Remember "Power (W) = Current (I) x (times) Voltage (V)" In your case: P = 1 x 50,000 = 50,000W In addition, its way too high to be supplied from an ordinary home power supply. What do you need that much power for? BTW, safety doesn't play a role...
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    NE567 Spice Model

    Hi all, After long period of searching, I couldn't find the spice model for the NE567 (by Philips, now obsolete yet I got it). Can anyone please direct me to where I can find it, or post the model for the NE567 Tone Decoder? I looked in the datasheet but no luck. I need it for Multisim 7...
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    Infrared Activated Switch

    Hi audioguru, How can rectifying and filtering a transformer’s o/p increase its voltage? I don’t find it logical. By the way, I have a NE567 Tone-Decoder IC and am wondering on how to use it to replace those IR receivers that gave me such a headache. Can I use it to receive IR light, using a...
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    Infrared Activated Switch

    Hi audioguru, Problems after Problems!!!! Grrrrrrrrrrrrrrrrrrrrrrrrrrrrrr. During the testing procedures, I used a 9v battery to power the 555 timers. Everything was OK. Now, I used a 220V-12V transformer to power the 555 timers. Problem. The IC quickly overheats. I checked for wiring errors...
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    Infrared Activated Switch

    Hi audiofuru, AGC?  ??? ;D
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    Infrared Activated Switch

    Hi audioguru, That picture you attached which shows the effects for DATA. Im just sending plain IR light at 56KHz. See image attached. BTW, range isn't that important. Probably 1-4 meters is what i'll need. What you say? ;D
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    Infrared Activated Switch

    Hi audioguru, I haven’t been getting to build the project because of some problems. First, my soldering iron is kind of busted and I couldn't get one. Well, not yet. Secondly, my sister is here, from another city, so we're spending some quality time. BTW, I was testing the IR receiver module...
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