Want to build a ohm meter

Discussion in 'The Projects Forum' started by electronucks, Aug 16, 2012.

  1. electronucks

    Thread Starter New Member

    Jun 16, 2012
    I would like to build a simple ohm meter like the one in the link below for my bench but dont know where to start . It looks to be pretty simple with very little circuitry . I would buy one but its never in stock so i thought id ask on how to build one. It looks to be using one of those china .38" 3 digit displays and ran off 2 AA batteries . Can anyone tell me how i could accomplish this?

  2. WBahn


    Mar 31, 2012
    I'm somewhat skeptical of their claim that it is accurate to 0.2%, but be that as it may.

    There are a number of kits out there to build your own DVM, you might look into some of them (I don't have any links to offer, but others might and you can also just Google things like "DVM kit" and see what you find, although since DVM can also mean Digital Video Monitoring and Doctor of Veterinary Medicine, you might have to tweak things (such as "digital multimeter kit).

    Okay, I went and did a few seconds of checking and found these to seed your search:


    Read the 2-star review.


    Please post what route you decide to go and how it goes.
  3. electronucks

    Thread Starter New Member

    Jun 16, 2012
    Those look cool but the main thing im looking for is a tiny size. Dont really need the whole multimeter. .39" like the one in the link is the perfect size. I can get the displays from china its just the circuit for a to read resistance on a display like that im really looking for.

    The one in the link i posted actually is accurate to .2ohm .I think the % is supposed to say ohm but could be percent. A few people i know have one and say its even more accurate then that. With atomizers the difference between .2ohm is a lot since they are usually sold in .25 ohm increments like 1.5,1.7.2,2.4 ohms.
  4. wayneh


    Sep 9, 2010
    That Elenco kit on Amazon cracks me up. $24 for a kit to build a meter that they sell for $4 and occasionally give away free at Harbor Freight. :rolleyes:

    If it was me, I think I'd either try to hack one of those cheap meters to read to a much lower ohms scale, or build an op-amp "helper" circuit, basically a constant current power supply to apply to the test unit. Then just measure the voltage required to hit the specified current. That's what the meter does already, but you might have to build your own if the meter can't be hacked.