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Electronics => Electronics => Topic started by: Melcin Powell on August 12, 2010, 01:28:35 PM

Title: Question about multimeter
Post by: Melcin Powell on August 12, 2010, 01:28:35 PM
well i just recently bought a Digital MultiMeter but when i try to read resistance i get the infinite resistance sign or it bounces everywhere and then goes back down to zero. What is happening? What am i doing wrong? The leads are not touching anything other then the resistor.
Title: Re: Question about multimeter
Post by: blackbeard on August 12, 2010, 01:32:34 PM
well there's the usual:

-try a different resistor
-change your batteries

and if neither of those work you should probably return it.
Title: Re: Question about multimeter
Post by: Melcin Powell on August 12, 2010, 02:03:59 PM
Ya well i did that but it is till freaking out. Thanks for the advice though
Title: Re: Question about multimeter
Post by: waltr on August 12, 2010, 02:41:22 PM
Touch the two probes together and it should show a few readings before settling to read less than one Ohm.
If this does work then first replace the battery as Blackbeard suggested.
Title: Re: Question about multimeter
Post by: Melcin Powell on August 12, 2010, 03:35:28 PM
Well thanks waltr, but i already returned it haha. So what digital multimeter would ya'll recommend i buy now?
Title: Re: Question about multimeter
Post by: blackbeard on August 12, 2010, 04:26:15 PM
Well thanks waltr, but i already returned it haha. So what digital multimeter would ya'll recommend i buy now?

if you have lots of money then get a Fluke. they're the best and they last a very long time!
Title: Re: Question about multimeter
Post by: Melcin Powell on August 12, 2010, 04:44:22 PM
Well i found one for only 60 bucks but i don't know much about them what do you think?

http://www.amazon.com/Mastech-MAS345-PC-Interfaced-Digital-Multimeter/dp/tech-data/B0006430ZM/ref=de_a_smtd/002-5032486-3423210?ie=UTF8&qid=1184724525&sr=1-1 (http://www.amazon.com/Mastech-MAS345-PC-Interfaced-Digital-Multimeter/dp/tech-data/B0006430ZM/ref=de_a_smtd/002-5032486-3423210?ie=UTF8&qid=1184724525&sr=1-1)
Title: Re: Question about multimeter
Post by: blackbeard on August 12, 2010, 07:14:40 PM
seems ok. a bit pricy for what it is though.
Title: Re: Question about multimeter
Post by: Melcin Powell on August 12, 2010, 07:25:40 PM
Well crud i sure don't want to buy anything pricey.
Title: Re: Question about multimeter
Post by: waltr on August 12, 2010, 07:40:46 PM
I have a couple of inexpensive DMMs that were made in Korea. One cost about $40 25 years ago and the second about $15 10 years ago. Both still work.

Any of these should be ok:
http://www.jameco.com/webapp/wcs/stores/servlet/StoreCatalogDrillDownView?langId=-1&storeId=10001&catalogId=10001&freeText=DMM&search_type=jamecoall (http://www.jameco.com/webapp/wcs/stores/servlet/StoreCatalogDrillDownView?langId=-1&storeId=10001&catalogId=10001&freeText=DMM&search_type=jamecoall)

Maybe someone else has a suggestion of a DMM bought recently.
Title: Re: Question about multimeter
Post by: Admin on August 12, 2010, 08:27:05 PM
Make sure the multimeter can measure frequency Hz - its invaluable for measuring PWM and servo signals.
Title: Re: Question about multimeter
Post by: tmoney68 on August 12, 2010, 09:35:15 PM
I have an Extech model 430. It measures everything including frequency and capacitance. I don't remember what I paid,but it was quite reasonable otherwise I wouldn't have bought it.  ;D