Connect with us

Cheap Frequency Counter

Discussion in 'Electronic Design' started by M. Hamed, Jun 2, 2013.

Scroll to continue with content
  1. M. Hamed

    M. Hamed Guest

  2. Phil Allison

    Phil Allison Guest

    "M. Hamed"

    ** The specs and price are normal for direct from China.

    The counter should work as advertised, such units have been around for a
    long time.

    The accuracy (20ppm) is nothing wonderful.


    ..... Phil
     
  3. John S

    John S Guest

  4. Jamie

    Jamie Guest

  5. Phil Allison

    Phil Allison Guest

    "John S"

    ** The specs look OK to me - too much sensitivity leads to unstable
    readings.

    The mediocre frequency accuracy of such counters results from a crystal that
    sits open on the PCB and so drifts with the local ambient temperature.

    If there is a trimmer cap next to it, one can set the accuracy to better
    than 1ppm using a broadcast frequency standard - assuming you are near
    one - or using a known frequency reference. But the drift issue remains.

    The biggest part of the temperature drift is mostly due to internal heat
    sources in the unit, workshop room temps being comparatively stable. So all
    you have to do is mount a small (ie 30mm) fan above the crystal, blowing
    room temp air onto it.

    Hey presto, no warm up drift.


    ..... Phil
     
  6. Guest

    yep same here, one cent over ~10 euro and they charge you 20euro
    handling

    -Lasse
     
  7. Jamie

    Jamie Guest

    How's it feel?

    Jamie
     
  8. Phil Allison

    Phil Allison Guest

    "Paul Colby"

    ** I can see a problem even in the pics on the page.

    IME red LED displays have really excellent legibility - even in a well lit
    workshop.

    Funny how they seem to be out of fashion.



    ..... Phil
     
  9. M. Hamed

    M. Hamed Guest

    Thanks All. The unit is on the way. I am having a hard time understanding the specs, aside from the obvious things, but it's Ok for now.
     
Ask a Question
Want to reply to this thread or ask your own question?
You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.
Electronics Point Logo
Continue to site
Quote of the day

-