[Canakas]

Hello all,

What are the necessary specifications for a multimeter, if my area of use spans from audio pcbs (mostly old ones) to basic computer layouts?

What are the ranges I need? like how high DCA ...ie 200mA
and at what precision i.e. is +/- 1.2% at 200mA any good

anyone have a brand they want to recommend, please feel free...
I am considering a finnish brand called BST but I dont know how good they are...

cheers
-canakas

 

[dsavitsk]

I have a whole stack of meters I got from Harbor Freight (with a 9V battery included) for $5 per. They do everything I have ever needed to do. Actually, I have another meter that measures capacitance (the HFs don't) so I measured some caps to see of the feature worked -- it did, my 0.1uF caps were really 0.09 or so, but otherwise the HF's have been great. They even measure and match transistors.

 

[splaz]

I agree with that, I've got a fairly cheap chinese/taiwanese thing. I've used it for pretty much everything. I didn't trust the really, really cheap meters, one is in my car just in case for some reason I need to do a bit of emergency auto electrical work.

Thinking of getting a nice automotive or auto-ranging one but can't justify the purchase at the moment.

 

[tomb]

Quote:

Originally Posted by dsavitsk /img/forum/go_quote.gif I have a whole stack of meters I got from Harbor Freight (with a 9V battery included) for $5 per. They do everything I have ever needed to do. Actually, I have another meter that measures capacitance (the HFs don't) so I measured some caps to see of the feature worked -- it did, my 0.1uF caps were really 0.09 or so, but otherwise the HF's have been great. They even measure and match transistors.

I agree with Dsavitsk except for one thing - the Harbor Freight meters are actually $3.99 and $2.99, depending on whether you get one with a back light. You will no doubt get posts that tell you nothing is as good as a Fluke. However, the only thing I've had reason to do that the cheapies didn't was measuring surface temps on hot chips. For that, I simply used Harbor Freight's upgrade meter for $19.99 (on sale) - my Fluke simply didn't have it.

For measuring bias and other things, these things are more than accurate enough. It's like everything else pretty much: it's the comparative readings that are important, not the absolutes. Resistor matching is easy because you are comparing them one to another, not against some absolute.

 

[luvdunhill]

I just got one of these little guys:

http://cgi.ebay.com/New-Digital-Mult...QQcmdZViewItem

Its h_fe measurement is decently accurate (which is why I bought it) and it works surprisingly well. I"d recommend a set of pigtail lead grabbers and your set! I believe this is the same meter as the Velleman 830-somethingorother which you can find via Froogle at similar prices as Ebay. Tangent has recommended the Velleman in a few threads around here as well.

Take care!

 

[Canakas]

Hi people,

Good to hear your advice.

I think ill go for the medium priced one that has these specs:

-diode test w/tone
- frequency
-resistance
-capacitance
-square wave generator

DCV 0-600V ±0,8%
ACV 0-200V ±0,8%
ACV 0-600V ±1,2%
DCA 0-20 mA ±0,8%
DCA 0-200 mA ±1,0%
DCA 0-20 A ±2,0%
ACA 0-20 mA ±1,2%
ACA 0-200 mA ±1,5%
ACA 0-20 A ±3,0%
OHM 0-2 Mohm ±0,8%
OHM 0-20 Mohm ±1,0%
OHM 0-200 Mohm ±5,0%
Capacitance 0-20 microF ±2,5%
Frquency 0-20 kHz ±1,5%
Waveform: squarepulse 50 Hz 2,3V p-p.


is 0-20mA low enough for use with audio electronics?

and is capacitance up to 20 uF high enough to use with older capacitors(the nice large ones in old mixers/amps and such)? I know a farad is a big measure... but still... I have caps the size of my thumb lying around...

Is the given precision for this meter satisfactory?

the more expensive one says this:

DCV 0-600V ±0,8%
ACV 0-600V ±1,5%
DCA 0-4 mA ±1,0%
DCA 0-400 mA ±1,2%
DCA 0-10 A ±1,5%
ACA 0-4 mA ±1,2%
ACA 0-400 mA ±1,5%
ACA 0-10 A ±2,5%
OHM 0-4 Mohm ±1,0%
OHM 0-40 Mohm ±2,0%
Capacitance 0-200 uF ± 4%
Frequency 0-10 MHz ±1,5%
Duty Cycle 20-80% ±3,5%

appreciate any opinions on this =)
man am I green...

-C

 

[tomb]

The 20uF limit for capacitors is not very useful. That will measure most film/box caps, but only the tiniest of electrolytics (the ones that come in the little cans). The ones as big as your thumb could be anywhere from several hundred uF's to thousands of uF's, depending on the size of your thumb.

 

[Canakas]

hmm. This means I should probably look a little further... and see if I can find one that has a 1 mF or maybe even higher...

Ill check out the caps I am talkin about and post back...

cheers
-C

 

[MN Ham Phones]

A dirt cheap multimeter will do fine for solid state work and the occasional repair around the house. But they probably have zero safety features for you or itself. This is how they cut corners to save money. You should get something better if you get into tube amps or measure line voltage often. Make a mistake (measure HV while in ohms for instance) and you can blow the meter and shred components inside. A good multimeter will have protection against this, while a cheapie can create shrapnel. Not a problem to replace a $10 meter, big problem if they hurt you in the process.

 

[dsavitsk]

Quote:

Originally Posted by tomb /img/forum/go_quote.gif The 20uF limit for capacitors is not very useful.

The only time you really need to measure caps is when you are building a filter of ome sort and value is critical. This typically means RIAA, which means very small values. 20uF is plenty by several orders of magnitude.

 

[Canakas]

hey ppl,

thanks for your advice! I love that you took the time to educate me a bit =)
I think ill get by with the cheaper one for now...

I know sound and not electronics as of now...
so I guess its better to see how far I get with the more reasonable priced one =)

-C

 

[tomb]

Quote:

Originally Posted by dsavitsk /img/forum/go_quote.gif Quote: Originally Posted by tomb The 20uF limit for capacitors is not very useful. The only time you really need to measure caps is when you are building a filter of ome sort and value is critical. This typically means RIAA, which means very small values. 20uF is plenty by several orders of magnitude.

The point was, why buy that meter - when as you say, measuring cap sizes is not that critical - at least not in the range provided by that meter. Personally, I think temperature is a much more useful metric with most of what we do. Otherwise, as we both suggested - get the Harbor Freight $2.99-$3.99 cheapies.

BTW, typical meter fuses will cost more than the Harbor Freight cheapie meters. So, even if you blow a meter - you're still ahead.

 

[Canakas]

this is all great advice - thanks a bunch!

Ill go with the cheapo then... the last argument sorta convinced me...
If anything blows its not a big loss...

cheers
-C