dear friends,
i have been asked to build a digital multimeter as a project,so as a start i thought to collect some information on current commercially available digital multimeters,

but for that i need the most important resource(as i think),,the DMM users!!!!
so i appriciate any comments on digital multimeters that you came across (if possible mention the product also)

and also you can give me your valuable ideas on this topic,,,,,(any thing related is welcome)............
thank you....

 

dear friends,
i have been asked to build a digital multimeter as a project,so as a start i thought to collect some information on current commercially available digital multimeters,

but for that i need the most important resource(as i think),,the DMM users!!!!
so i appriciate any comments on digital multimeters that you came across (if possible mention the product also)

and also you can give me your valuable ideas on this topic,,,,,(any thing related is welcome)............
thank you....

Where I live we have a hardware store called Harbor Freight which routinely gives away DMMs which otherwise sell for $3.99. Believe it or not, it's not bad. They're very handy to have around (workshop, garage, upstairs, downstairs, etc.) and include a battery.

My point is, if you really want to reverse engineer one of these, just go get one and build a wooden box around it. Done.

 

You can always build something around an IC - http://www.intersil.com/products/deviceinfo.asp?pn=ICL7107

Without specs, it's hard to say much. Can you beat the ruggedness of a Fluke DMM?

 

Unless this is a school project this is a case where you can buy dramatically cheaper than you can make it. As mentioned by Wayne you can buy an off the shelf meter for $3. If you build one for $30 you are getting off light.

Are you wanting a theory of operation or something?

Basically it revolves around counters, much like a frequency counter. When I was going to school they taught dual slope A/D converters were the way, but there are other methods that work.

 

Where I live we have a hardware store called Harbor Freight which routinely gives away DMMs which otherwise sell for $3.99. Believe it or not, it's not bad. They're very handy to have around (workshop, garage, upstairs, downstairs, etc.) and include a battery.

My point is, if you really want to reverse engineer one of these, just go get one and build a wooden box around it. Done.

gud point but im suppose to build my own and submit it with its circuit diagram,working properties such as range&error%,..etc so i think your idea wont work well.but anyway thanks for the reply and if you have any circuit diagrams or any ideas of constructing a DMM please post it.

 

Should be in the homework section.

 

plzzzzzz any body with any circuit diagrams???????????

 

plzzzzzz any body with any circuit diagrams???????????

We can help you with advice or give you a push in the correct direction. But I doubt you will get any turnkey ready solution for your homework. So my advice to you is just. Start working and if you feel you need some help just ask the forum for help.

 

Research Dual Slope A/D converter.