0
\$\begingroup\$

Can anyone tell me how to check a 2 pin crystal oscillator using multimeter. My oscilloscope isn't working.

\$\endgroup\$
7
  • 2
    \$\begingroup\$ I don't think you can. But maybe edit your question to include a picture along with the make and model of your multimeter so people can look up the manual and see if it is possible. Or you can just link to the manual online if you know where it is. \$\endgroup\$
    – user57037
    Commented Aug 24, 2021 at 3:28
  • 1
    \$\begingroup\$ I have bags of 2-pin crystals. But they aren't, by themselves, oscillators. They are just crystals. There are also 4-pin oscillator cans, accepting power and providing an output. None of these can be checked with most multimeters I'm familiar with. Completely agree with @mkeith about that. You can build circuits to test them and provide human perception indicators. But the entire topic would fill a chapter or two. Better that you provide everything you have about it, on hand. Maybe some idea can show up. \$\endgroup\$
    – jonk
    Commented Aug 24, 2021 at 3:48
  • 1
    \$\begingroup\$ @Ishwaran I've learned the hard way that watch makers keep a great deal of their knowledge close to their chest. It's also almost certain to just be a crystal and not an oscillator. They do some very special things inside a watch surrounding the crystal. Stuff I struggled to learn from and... well... I still need to spend more time learning, I think. They get years of time out of these things, which I can only hope to achieve someday. That doesn't mean you cannot use it. You can. You just won't get as far as they do with it. Anyway, you won't be able to "check" it, simply. You need a circuit. \$\endgroup\$
    – jonk
    Commented Aug 24, 2021 at 3:59
  • 2
    \$\begingroup\$ @Ishwaran: what Jonk is trying to tell you is that if it has two pins, it's not an oscillator -- it's just a crystal. If it's a little cylinder about 1 to 2mm in diameter and 4 to 10mm long, with two wires sticking out -- it's a crystal, not an oscillator. (And yes, it's physically possible to make a two-pin oscillator, with crystal precision. But that would be nonsensical for nearly all practical purposes. If it's got two wires, it's just a crystal, not an oscillator). \$\endgroup\$
    – TimWescott
    Commented Aug 24, 2021 at 4:27
  • 1
    \$\begingroup\$ If you know basic soldering, you can build a simple clock with some 74HC binary counter IC (in cascade) and LEDs. Put a button on reset pins, then clock with a stop watch how long it takes until a certain bit gets set. (total time/ticks)^-1 = oscillator frequency. \$\endgroup\$
    – Lundin
    Commented Aug 24, 2021 at 11:15

1 Answer 1

4
\$\begingroup\$

It isn't possible. The crystal should be first inserted into an oscillator circuit and its output signal is to be read by a frequency meter or by a multimeter with the frequency meter function. The only instrument which is able to read a crystal frequency is a dip meter, a multi-purpose instrument used by radio amateurs.

\$\endgroup\$
3
  • \$\begingroup\$ It's been decades. Do they still call them grid dip meters? +1 \$\endgroup\$
    – jonk
    Commented Aug 24, 2021 at 4:03
  • \$\begingroup\$ @jonk No, they call it now "transistor dip meter"; it works fine also without grid! \$\endgroup\$
    – Paolo
    Commented Aug 25, 2021 at 6:18
  • \$\begingroup\$ Thanks! It's been decades for me. So thanks for updating my old memory on this! ;) We used to use vacuum tubes, back in the day. Haven't done this since I was a kid! \$\endgroup\$
    – jonk
    Commented Aug 25, 2021 at 6:24

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.