Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Help finding an op-amp

  1. Jul 17, 2012 #1
    Hey everyone,

    Whelp, I've had this project dancing around in the back of my mind for a good six months now and I'm here to ask for some help. I'd like to build this biofeedback device from an old issue of Popular Electronics:

    The problem I'm running into is that the op-amps (Signetics N5556) are old and just about impossible to find. I've checked all of the electronics outlets I can think of for them, and the other parts were easy enough to source. Does anyone have a link to a shop that would carry something obscure like this? Barring that, could anyone suggest a substitute that's readily available?

    I'm just a hobbyist that enjoys building weird things so I apologize if this is a goofy question. Any expert advice would be GREATLY appreciated. Thank you!
  2. jcsd
  3. Jul 17, 2012 #2
    Simply use TL071 instead of N5556.
  4. Jul 17, 2012 #3
    There are many choices that would likely work, because this was a fairly crude technology. The TL071 is probably good. Otherwise, I'd suggest an OPA277, which has fairly close characteristics and is based upon the same technology.
  5. Jul 17, 2012 #4
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook