Shop OBEX P1 Docs P2 Docs Learn Events
recording sound with Piezo speaker — Parallax Forums

recording sound with Piezo speaker

japerjaper Posts: 105
edited 2005-10-11 02:14 in BASIC Stamp
hello
could i use a Piezoelectric speaker as a microphone to record frequency into basic stamp
would like to stay with the kit material of BAAD and What a Microcontroller
is this Possible.
i'll do the work just need to know if this is an option.
just looking to actually do it,not looking for high fidelity

thanks

Comments

  • Chris SavageChris Savage Parallax Engineering Posts: 14,406
    edited 2005-10-10 19:35
    It is possible to use a Piezo Speaker as a microphone pickup.· Frequency response will be limited, and sensitivity will be an issue.· You will definately need an Op-Amp such as the LM358.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Chris Savage
    Parallax Tech Support
    csavage@parallax.com
  • japerjaper Posts: 105
    edited 2005-10-10 20:25
    Thanks Chris,
    Just happen to have a 358 Op-Amp that came in the BAaD Course
    due to limitation of memory and Keeping true to the course,
    I am just looking to perform the task.
    Looks very Challanging and Am looking forward to it.
    Thanks again Chris
    japer
  • Chris SavageChris Savage Parallax Engineering Posts: 14,406
    edited 2005-10-10 23:04
    You probably won't be able to do more than detect sound.· What you will need to do is configure the op-amp as a comparator (Or as an amplifier) so that a small signal detected on the inverting input creates a larger change on the output.· You can use the non-inverting input as a reference voltage if you're using it as a comparator, or you can re-configure it for use as a signal amplifier.· There are plenty of references online for doing that.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Chris Savage
    Parallax Tech Support
    csavage@parallax.com
  • japerjaper Posts: 105
    edited 2005-10-11 02:14
    hello
    i was thinking of boosting the signal with an NPN and some caps maybe
    but the OP-Amp is a single source and proabaly the best space saving
    solution.It's defently an off the wall challange for the chapter
    But the deeper you get the deeper it gets
    thanks again
    japer
Sign In or Register to comment.