It works; care to guess what it is?

Discussion in 'The Projects Forum' started by tracecom, Sep 9, 2012.

  1. tracecom

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    Messy breadboard, but it worked the first time I applied power.
     
  2. ErnieM

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    My guess is a 555 based audio tone generator.
     
  3. tracecom

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    It has to do with "tones," but it doesn't generate them and there's no 555.
     
  4. MrChips

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    It's a transistor mic amplifier driving an LM386 speaker amp.
     
  5. tracecom

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    Close enough. The transistor is a JFET and the amp is for a guitar. It has a drive control, a gain control, a tone control, and a "grit" switch.

    I am going to build it on perfboard, and mount it (and a battery pack) in something like this.
     
    Last edited: Sep 9, 2012
  6. absf

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    Amplifying guitar using a LM386? How does it sound like? Electric or Acoustic?

    Allen
     
  7. tracecom

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    I haven't hooked this one to a guitar yet, but there are lots of You-tube videos about similar amps. Search for Ruby Amp and Noisy Cricket. Some of them sound quite good. I think one of the keys is the JFET front end and the high impedance it provides.
     
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  8. absf

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    That was really CoooooL! I hope there's no cheating on the Youtube videos.:D

    I'm gonna make one when I'm free, may be next month. I have all the spares except the jfet. Is 2SK30A a jfet or do I have to get a 2N5951?

    Allen
     
  9. THE_RB

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    There were a number of brands of small (portable) commercial guitar amps using LM386 and one or two 9v batteries. With a good speaker choice they were surprisingly loud, especially if you didn't mind some clipping. :)
     
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  10. R!f@@

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    Yippeeeee!

    My 555 Vibrator works. ! Er ..! Astable i.e.
     
  11. tracecom

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    Most designs use a MPF102 or equivalent. That's what I am using.
     
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  12. THE_RB

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    Electric guitars with magnetic pickups easily produce 05.v to 2v peak to peak and will drive an LM386 directly, you actually have to turn it right down to avoid clipping with most pickups.

    You only need a FET preamp before the LM386 if you are using a microphone or fussy (passive non amplified) acoustic pickup on an acoustic guitar.
     
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  13. absf

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    My Fender has 2 pickups and 3 tone controls and my acoustic guitar has a little pre-amp box mounted on the side run by a 9V battery. Not sure what the pickup looked like. Most probably using piezzo disc.

    Allen
     
    Last edited: Sep 11, 2012
  14. MrChips

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    Wonder how many musicians we have here on AAC?

    Would all the musicians please stand up?

    Do bagpipes count?
     
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  15. tracecom

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    That made me smile! :) (Can one play bagpipes sitting down?)

    Speaking of piezo transducers, does anyone know if there are spec's for them that make one better than another to use as guitar pickups?
     
  16. R!f@@

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    What the heck is a bag pipe.
    Is it tht thingy tht I see in movies where teens smoke the brains out through a extremely large smoke pipe looking glass thngy....!
     
  17. gerty

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