Help on color organ please

Discussion in 'The Projects Forum' started by Blacky11, Jun 7, 2010.

  1. Blacky11

    Thread Starter New Member

    May 27, 2010
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    0
    Hi, some of you might remember me asking this question about a week or so ago. I took a little break off this project since I had some things I had to do. I looked up a different color organ since the one I had at the beginning was for lamps and not LEDs. The schematics im using now is this one:
    http://www.electronicpeasant.com/projects/ledlamps/ledcolor.html
    On this schematic I built the microphone part, the batter part, and ONLY the low 50k pot up to the first LED. I did this just to test one of the frequencies first but i cant get it to light up with music that has a lot of heave bass. I played around with the 200k to set the sensibility but nothing. Played around with the 50k pot and nothing again. Is this schematics incorrect or am I doing something wrong?
    Also I noticed that all 3 sets of LEDs are built different in the sense that they have different resisters and different capacitors, why is this?

    Thanks,
    E
     
  2. hobbyist

    Distinguished Member

    Aug 10, 2008
    764
    56
    How does that work when the 2sa1175's (PNP) are hooked up backwards.

    The emitter should be on the positive rail and the collector to the base resistors of the LED drivers.
     
  3. Blacky11

    Thread Starter New Member

    May 27, 2010
    9
    0
    aaaaa, yea I forgot to mention on this post like i did on the last one. I dont know much about circuits. So you saying that doesnt mean anything haha. How would i go about fixing this to work? I know the difference between the emitter, the collector, and the base on the transistor, so which way do i flip it?
     
  4. hobbyist

    Distinguished Member

    Aug 10, 2008
    764
    56
    Flip the 2sA1175 (PNP) transistor so that the arrow (emitter) is connected to the positive side of battery. And the collector terminal is connected to the 47K ohm base resistor and 4.7uf cap.
     
  5. Blacky11

    Thread Starter New Member

    May 27, 2010
    9
    0
    hmm, I have flipped it how you have said but it still doesnt light up the LED after playing around with both pots.

    EDIT: am I suppose to flip all the PNPs this way?
     
  6. hobbyist

    Distinguished Member

    Aug 10, 2008
    764
    56
    Do you have any kind of test equipment, such as a multimeter, and a signal generator? For doing troubleshooting with.

    Can you draw up a schematic of what you have at the moment, to do some analysis on.

    Because when trouble shooting a circuit like this, you need to check voltages, as well as tracing a signal produced by a (function signal generator), to see what is working and where the signal gets lost.

    Here is some tips you could do right now to do some preliminary trouble shooting.

    1. remove the complete audio amplifier circuit, (2 transistors at the very left side) containing the mic.
    Disconnect it from the rest of the circuitry.

    2.remove both 100K resistors and the 100pf cap. on the left side of the 3rd. transistor.

    3. remove the 0.01uf cap, on the right side of the same 3rd transistor.

    4. conect the collector of the 3rd transistor up directly to the base of the 2sa1175 transistor. Make sure 2sa1175 emitter is conected to the positive side of the battery.

    5. using a 2K ohm resistor connect it directly to the base of the 3rd. transistor.

    6. with this conected touch the other end of the 2K ohm resistor to the positive side of the battery, and see if the LED lights up.

    If it does than you start moving towards the front one step stage at a time.
     
    Last edited: Jun 7, 2010
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