Multimeters: Which one?

[chromesphere]

Hi all,
Ive been instructed to find myself a present for xmas.  Just so happens my current cheapy multimeter is playing up a bit.

I thought this would be an easy discussion as the budget is 100-150, should be able to get something good without much question.

Problem is, i have no idea which one to get.  I was looking at a fluke 77 iv (shipped to oz is about $200 so over budget), but i've heard its no good for ua range and picofarad range (accuracy wise):
http://www.fluke.com/fluke/usen/digital-multimeters/Fluke-77-IV.htm?PID=56126

I then considered the BK Precision 2709, but have noted that its accuracy isnt good at this range either:
http://www.bkprecision.com/products/multimeters/2709B-auto-ranging-true-rms-tool-kit-digital-multimeter.html

When i say "isnt that good" im comparing it to my current DMM which was $20 from my local electronics shop i bought 10+ years ago:
http://shop.efo.net.au/zencart/index.php?main_page=product_info&products_id=267

I know, guitar pedal stuff doesnt need to be super accurate, but I would have thought when spending that sort of coin you would expect to upgrade in accuracy of readings?

A couple of important things (to me) are fast readings and continuity, auto-ranging (seems pretty standard these days) and capacitance reading to the pf range (i have never had it before believe it or not).

So what do you guys use / recommend?Thanks for your input / advice!
Paul

[kodiakklub]

fluke fluke fluke fluke.

the 77 is perfect for anything pedal and amp wise. it does capacitance and diodes and mV DC so you can set your bias on a tube amp if you have one. and fluke is bullet proof. you will never buy another meter again.

[chromesphere]

Thanks for the info kodiakklub!

I was asking my question over at the EEVBlog, i think most of those guys are into high voltage stuff and have lead me astray a bit...

I havent seen a review or even a 77iv in action so i would really like to ask you a few questions if you would be so kind?

- Does the meter respond quickly to range changes?
- Is the continuity buzzer quick to respond?
- Does the meter measure in ua's?  (like...10ua for instance)
- Does the meter measure in picofarads?

They are the main things i use / care about.  Its alot of $$ for a meter, i want to make sure i get the right one.

Thanks for your time!
Paul

[davent]

If you've got the time, I've always found this guy informative and entertaining.

Beginner guide. http://www.youtube.com/watch?v=gh1n_ELmpFI

Reviews, $50 models. http://www.youtube.com/watch?v=ZoeUgMFLyAw
$100 models http://www.youtube.com/watch?v=n3WGaiYF2sk

dave

[armdnrdy]

I have a Fluke 87V works great, no complaints accept one....The frequency range.

I discovered my meter's limitations when I built my first (MXR) flanger. I was taking a reading of the sweep, I watched as the LCD readout kept climbing, when suddenly around 700-800k the screen went blank. After a bit, the meter displayed a reading again around the same frequency as when it disappeared. I couldn't figure out what was going on!

Finally I broke out the user manual and checked the frequency range. Surely it couldn't be going out of range of this fine piece of test equipment............It was!!!  My $400.00 meter was only rated for 200kHz!!!! I'll give it one thing, rated for 200 but measuring up to 800.

I had to purchase a frequency counter to make up for the limitations of the Fluke.

chromesphere,

Take a look at the frequency specs of both. (Unless you have a counter) The Fluke is rated for 99.99K and the BK is rated well into Mhz.

Before I purchased my counter, I had to borrow a friend's Extech meter to adjust the sweep range on an ADA Flanger project that I built. (1.3 MHz)

[chromesphere]

Hey Davent, thats the videos i watched that got me to this point

He seemed to like that B K precision, i agree it looks good.  It was concerning to see the 'lag' on the continuity mode on some of these 100ish DMM.  Id prefer my unlatched $20 dmm's continuity mode then have to wait like, a second, for it to beep.  checking pcb's with that lag would be a pita...The bk precision was very fast though.  Its around $150 shipped to oz.  an extra $70 gets me the Fluke 77 iv.  

Never thought buying a DMM would be so hard / expensive...I'm sure a $50 dmm would do just fine as well, but i did want something that would last a long time, and have a decent capacitance meter as well.

Edit: Armdndry, thanks for the info on the frequency meter.  I have actually never used a frequency meter before.  I'm getting pretty mental on the whole DIY guitar pedal thing though, so maybe i will use it at some stage.  Thanks for pointing that out!

Paul

[PRR]

> something that would last a long time

Get five $20 meters.

If the last one lasted 10+ years, a 5-pack lasts a lifertime.

And there ARE situations where 2 3 or 5 meters at once gains better clues. (Smoke-testing a big amp, I watch power voltage, bias voltage, output DC current, and output power, or as many of those as I can.)

> capacitance reading

I never had that until recently, and I have not even tried it on my new meter. A box-lot of small caps just seems easier to me than poking at caps.

[reveal]

Consider buying a dedicated capacitance meter. I wish I could recommend one but I haven't built the one I bought  :icon_rolleyes:yet.   

[chromesphere]

The Fluke looks like its not really suited for small scale electronics.  I keep seeing posts by Dave at EEVBlog saying it doesnt measure uA.  Thats no good, so im going to move onto the BK Precision.  It seems to measure everything from picofarads it microamps.  THe only draw back with it is that it has an annoying beep when you change the dial but i read someone taped over the speaker to quieten it.

PRR im going to keep my cheapo for that purpose.

Paul

[Jdansti]

My wish list of features:

-Auto-ranging
-True RMS - We've used a cheapie non-RMS meter at work to measure voltage and got squirrelly results. The true RMS meter sorted it out. I've noticed that my non-RMS meter can't measure AC ripple on a rectified DC power supply.
-Frequency - Mainly because I occasionally use a gas powered generator, and you sometimes have to tweak the throttle to get 60Hz.
-Reads voltage and resistance without having to move the hot probe's plug. I was once given a DVM as a gift and it has separate jacks for voltage and resistance. PITA!!!
-Audible continuity function.
-Upper resistance range >/= 20M.
-Has a decent kickstand that doesn't fold up and cause the meter to fall over when you press a button.

I'd like a Fluke 175, but I don't want to pay over $250 for one.  I'm thinking about the Amprobe 37XR-A true RMS meter.  It also measures inductance which would be nice for making wah inductors.   Looks like a good deal for $120: http://www.amazon.com/gp/aw/d/B0012IUYK0

[Rob Strand]

I think those very cheap meters are very much hit and miss.   The accuracy, when they work, seems quite OK.  However after 1 year they can suffer from things like flakey switches, bad solder joints and generally erratic behaviour.    After going through two crap ones at my work,  I've reached the point where I'm totally sick of using meters that produce "measurements"you cannot trust.  Now I would happily pay $100 instead of $30.    Unfortunately I can't  comment on lesser known brands with $50 or more price brackets.

The cheaper flukes are very reliable but yes I will agree that the lack of a low current scale can be annoying.

I then considered the BK Precision 2709, but have noted that its accuracy isnt good at this range either:

You will find the accuracy of units from reputable companies like Fluke and BK Precision are guaranteed to *agree* with the specs.  In reality they are often much more accurate, especially on DC and resistance.  Even with that knowledge, I would be hesitant to buy a meter with 1% accuracy on the resistance, the 0.5% to 0.7% mark seems more like it.

Unfortunately the cost quickly escalates if you want 1)  high accuracy,  2)  high accuracy AC,  3) wider bandwidth AC (ie. > 1kHz).   

[davent]

In what situations are people directly measuring current, (a pain because it's measured in series)? I always just measure voltage drop across a resistor and plug that info into ohms law to calculate current. For measuring total pedal current i boxed up a 1Ω between two power jacks, power plugged into one, pedal plugged into second,  measure the mV drop across the resistor which directly reads as mA etc...

dave

[roseblood11]

Search for VC97 on ebay... It's cheap, but pretty good quality. And it can do everything you'll need for building pedals and amps.

[oldschoolanalog]

I got this one as for a Christmas present several years ago and have been very happy with it. The max/min hold feature is great for LFO work. The cap function is a bit limited.
http://www.bellnw.com/manufacturer/BK-Precision/389A.htm
Read the pdfs at the bottom of the page for more details.
I'm sure it can be found for a lower price. Shop around.

[Perrow]

Consider buying a dedicated capacitance meter. I wish I could recommend one but I haven't built the one I bought  :icon_rolleyes:yet.  

I got me one of these: http://www.uni-trend.com/UT601.html

From fractions of Ohms to 2000M ohms (the higher ohms settings are "for reference only" but has proven useful), and from pF's to 20mF. Covers pretty much anything a stompbox would need as far as resistors and caps.

In what situations are people directly measuring current, (a pain because it's measured in series)? I always just measure voltage drop across a resistor and plug that info into ohms law to calculate current. For measuring total pedal current i boxed up a 1Ω between two power jacks, power plugged into one, pedal plugged into second,  measure the mV drop across the resistor which directly reads as mA etc...

dave

That's exactly what's going into my bench supply as soon as I find the time to mod it. Bought a four digit led 0-3.3V meter on Ebay for display.

[PRR]

> In what situations are people directly measuring current

Over several decades of circuit plonking..... maybe twice?

There almost always is, or can be, a resistor which can be Volted.

One use FAR from the present discussion: The total power into my fusebox. In trying to measure this I found that my Fluke didn't read current at all! I got it pre-owned, and both current fuses were blown. They are quite expensive. This alone discourages casual current checks. (And Amping a fusebox isn't practical except I have the Clamp-On probe which does not require breaking the circuit and resetting all the clocks in the house.)

I also can't think of audio uses for 1% precision.

Also I am not a big fan of "true RMS" except that it means you didn't get the cheapest sort of AC detection.

Power ripple almost always needs a C-R filter to block DC. (That's standard on old VTVMs but seems to be rare in DMMs.) True, this is one place where Peak, Average, and RMS give different numbers; but (if all references to Sine) not that different, not if you are wondering if ripple is a huge problem or not.

[oldschoolanalog]

Really depends on the type of f/x you build too. For a flangerholic like me the f counter & Max/Min hold functions are a real plus. I still use my old $20 RS meter too. I have had that thing for ages and it still performs all the "basic" functions well.

[petey twofinger]

VC97

http://www.ebay.com/itm/VC97-3999-Auto-range-multimeter-vs-FLUKE-15B-tester-DC-V-AC-V-Resistance-Frequen-/300774399328?pt=LH_DefaultDomain_0&hash=item46078d1d60

30 bucks ?

tell me a lil more about this , presntly i have a cheap 17 dollar one , but it has lasted forever . i got a 10 dollar super cheapo to do hfe but the sockets dont work .

is the vc97 quality ? does the hfe test work well ?

it does capacitance measurement well too ?

[electrosonic]

I just got one of those. Haven't had a chance to use it much but the quality looks OK. Mine was $28 with free shipping. I bought it based on the review here...

http://www.robotroom.com/Multimeter-Reviews.html

Andrew.

[chromesphere]

In what situations are people directly measuring current

Mainly, when checking collector current / leakage on germanium transistors (to work out the hfe).
Paul