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  1. Alec_t

    Make electronics experiment 11

    According to this article, that circuit is driving an LED, not a speaker. Further amplification, using a power transistor, would be needed to get any significant volume from a speaker.
  2. Alec_t

    Working on a 3-voice 40106 oscillator. Need help...

    Yes. A few mA through a diode is enough to get a decent voltage drop, ~0.6V for a normal silicon diode such as a 1N4148 or 1N400x. Don't forget you will need some current-limiting resistance in series when testing. The coupling resistance (Rc) needs to be considerably higher than the...
  3. Alec_t

    Working on a 3-voice 40106 oscillator. Need help...

    It depends on how much current flows through the diodes and your measuring circuit. At very low currents the voltage drop will be much smaller than the ball-park figure of 0.6-0.7V normally quoted for a silicon diode. Adios.
  4. Alec_t

    a transistor is a variable resistor

    No matter how wide open your mind is, you can't alter the experimentally-verifiable physical facts of electronics.
  5. Alec_t

    Working on a 3-voice 40106 oscillator. Need help...

    Here's another approach for a chanter sound attempt, using one '40106 oscllator and a '4013 forming two divide-by-two stages : The second divider, first divider and oscillator generate the fundamental tone, the second harmonic and the fourth harmonic. respectively. These are mixed by R2/3/4/5...
  6. Alec_t

    Working on a 3-voice 40106 oscillator. Need help...

    No. I'm older than you so the third tone is weaker to me :). No. It was still running. Yes. But increase the value of the resistor coupling adjacent oscillators. Here's a test simulation circuit for 2 stages, plus the resulting sound file.
  7. Alec_t

    Working on a 3-voice 40106 oscillator. Need help...

    No. My comment was about the output of the IC, not its supply voltage. Then your perception of the tones now doesn't correspond with the reduced perceived loudness of higher frequencies which you reported earlier. That suggests something wasn't/isn't wired exactly as you thought it was. Redraw...
  8. Alec_t

    Working on a 3-voice 40106 oscillator. Need help...

    Here's the Chanter (post #16 circuit) sim result .wav files (delete the .txt extensions). The Sample Key resistance was 100k for the first 2 seconds and 20k for the following 2 seconds. Chanter.wav is for the square wave output from the final oscillator of the circuit: Chanter2.wav is for the...
  9. Alec_t

    Working on a 3-voice 40106 oscillator. Need help...

    Yes. Just to demonstrate that the oscillator output amplitude is virtually constant with change in frequency. Did you play the wav file? If so, did you hear any change in amplitude as the tone changed? There is bound to be a change in the overall pulse train, because the oscillators are being...
  10. Alec_t

    loudness question

    Since neither is specified as an AC signal in the audio frequency range, in both cases all you will hear presumably is a click.
  11. Alec_t

    Working on a 3-voice 40106 oscillator. Need help...

    Perhaps there's a wiring error somewhere. I've simulated the '40106 single oscillator with LTspice, which shows it should operate all the way up to ~1MHz. I ran the sim with a 100nF cap and resistor values of 12k, 6k and 3k in turn, giving fequencies of 1.27kHz, 2.48kHz and 4.48kHz...
  12. Alec_t

    Replacement micro switch for my mitre saw

    @DIYrep This thread is over 2 years old. The OP is unlikely to reply.
  13. Alec_t

    Working on a 3-voice 40106 oscillator. Need help...

    In that age range, presbycusis (age-related hearing loss) is very common. People can be unaware that they are affected by it, but it may be part of the reason your higher frequencies seem quieter. Above ~1kHz, apparent loudness drops off surprisingly rapidly with frequency.
  14. Alec_t

    music amplifier with just resistors (falstad simulation.)

    Even if that were true (which it isn't), 'cancelling the power' would lead to zero output, not amplification.
  15. Alec_t

    Working on a 3-voice 40106 oscillator. Need help...

    What are you using to listen to the oscillator output? Amp/preamp details? What age group are you in? Youth, young adult, middle age, senior citizen?
  16. Alec_t

    Transistor amplifier circuit

    Welcome to maker.pro! The circuit won't work, because Q3 is upside down. Once that's corrected, plug in some component values and let LTspice show you how the circuit behaves. BTW, it always helps if you post your .asc file. The forum can accept that format as an upload.
  17. Alec_t

    Potentiometer joystick

    But what current does it draw (or what is its resistance)? Can you post a link to the valve's datasheet? What power supply are you intending to use?
  18. Alec_t

    Where to buy shielded jumper cables?

    Breadboards are notorious for flaky connections. You may have to bite the bullet and solder the connections.
  19. Alec_t

    Air Hockey Score Board - Need silicone conductive button

    Sounds like a solution.
  20. Alec_t

    passive gate chain amplifier

    Using just passive components you can amplify pulsed voltage or pulsed current, but you can't amplify both at the same time, since output energy is always less than input energy.
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