Why most multimeters range is 2v 20v 200v instead of 9v 99v and 999v

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Surely the true maximum reading is 1.999.
The "1" is not a full digit saving the cost of another full digit.
Modern cheap meters do indeed have full 4 digit displays just like one I bought a few months ago.
an8008 - Buy Cheap an8008 - From Banggood

I agree, this DMM has great value for price. Dave Jones on EEVBlog reviewed it : YouTube.
I now got one, as a second DMM. It's large and high contrast display is a very nice feature. Buy it only from the manufacturer (Aneng) official shop within banggood or AliExpres.
 
I didnt mean the number of digits!!!!
i meant the fact that its 2.whatever instead of 9.whatever

Why do they only display 2 instead of 9?? That makes it less accurate at 5v and stuff

For example your measuring 5v

if the range was 9.x instead of just 2.x it would be more accurate!
Why does it only go to 1.999 instead of 9.999 for example!!
 
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I didnt mean the number of digits!!!!
i meant the fact that its 2.whatever instead of 9.whatever

Why do they only display 2 instead of 9?? That makes it less accurate at 5v and stuff

For example your measuring 5v

if the range was 9.x instead of just 2.x it would be more accurate!
Why does it only go to 1.999 instead of 9.999 for example!!

The Converter used in DMM are usually ramp A/D converter (double or more ramp). They basically build around a ramp generator a comparator and a counter. The main characteristic of those converter is their Count number. Most of them are 2000 counts, 5000 counts or 10000 counts. 2000 counts means first count=0 and last 1999. That's why ranges are 2 on various power of 10.
With these kind of converter, count number as an incidence on digits and maximal theorical reachable accuracy.
So most common DMM are (or were...) 2000 counts. My old ITT Metrix one is 5000 and the Aneng on the previous posts is a 10000. Not so bad for less than 20€ !
 
I believe they started using the 1/2 digit back when digital meters first came out because they would actually use a counter type ADC and it was cheaper to use three decade counters with the carry outputs daisy chained, and then use the last carry output as the leading 1/2 digit. Got you a max count of 1999 rather than 999 without adding another counter chip.
 
Why most multimeters range is 2.0000v 20.000v 200.00v and such
instead of 9.9999v 99.999v and 999.99v and such

Wouldnt 9 make more sense and be easier to use???? More decimal range and more accuracy at lower voltages!!!

certainly
its in the counter and the display & driver. 2000 counts is 0-1999.
the display's most significant digit is either a 0 or 1 which simplifies the hardware, it uses Boolean math and a flip-flop to get double the counts uses only portion of a digit or 1/2 ( I think the early ones displayed either a blank or a "1" its a 1 segment instead of a 8 segment display. The early displays where led segments or nixie tubes and you built them one digit at a time.

Or they could give you 999 counts or double 1999 counts for the same costs, Most take the higher count every time.
 
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Its a historical artifact when 3 1/2 digit multi-meters were the norm. E.g when standard logic gates /counters ruled the day.
It gets carried over to higher and higher counts or digits when displays and logic costs are buried in LCD & CMOS ASIC's and the digits tend to correspond more towards accuracy and uncertainly capabilities & where the money is.
 

PRR

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My Heath 2.5 digit DMM had two Nixie tubes and a NE2 lamp for the leading "1". "199" was twice as good as "99" and not twice as expensive.

9999 is not a magic number, except when finger-counting.

Actual accuracy is what you pay for. That old Heath was barely accurate to 199. $5 meters today are fairly accurate to 1999. The hi-buck brands introduced 3999 as a step-up, while not adding a full decade counter and 2.5X even more accuracy. 19999 count is available but at far higher price. 10 cents for the extra decade and hundreds of bucks for all the super precision so that the last digit isn't random noise.
 
Has anyone yet ran into an AUDIO requirement for more than 3½ digits ("±1999") yet, really? I haven't. Not balancing finals in push-pull. Not specifying resistors in a stepped attenuator. Nothing.

Seriously… be happy with your $5 (or in my case $29) 3½ digit multimeter. Use it until it breaks. Chuck it, get another one. Smile all the way to the bank.

GoatGuy
 
Has anyone yet ran into an AUDIO requirement for more than 3½ digits ("±1999") yet, really? I haven't. Not balancing finals in push-pull. Not specifying resistors in a stepped attenuator. Nothing.
GoatGuy

There's a lot of 1% or 0.1% resistor spec'ing when paralleling power amp chips. I know you will counter argue to just buy them to the tolerance you need and just use a 3.5. That's fine.
 
There's a lot of 1% or 0.1% resistor spec'ing when paralleling power amp chips. I know you will counter argue to just buy them to the tolerance you need and just use a 3.5. That's fine.
Remember the absolute accuracy is not important, after all it is matching or finding the differences or ratios. So using the same meter and range most measurement error terms are nulled.
Even then a 1% DMM in resistance function gives good enough accuracy to meet the same gain error budget using expensive 0.1% parts.
 
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Whatever you choose for full-scale means that some readings will be less accurate, if (as is usual) decades are used. A solution is to use both 10's and 3's, but few meters do this.

One way to look at 1.999 is to think of it as 1.000 plus some extension. It would be annoying to measure something varying from 0.99 to 1.01 on a 1.000 scale.

The right answer, if having a range change involves a gain switch, you can't get maximum resolution at the transition point. A standard cell in the old days was 1.018V at STP which could have made 1 plus a little very useful.

The 1/2 digit thing goes pretty far back. I know Keithley liked the 1, 3, 10, ... sequence anyone else?
 
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My reply could lead to another thread. One of my deepest pet peeves in the audiophile world - especially by those who can't/don't/won't actually pursue the math.

Basically “spec'ing ultra precision resistors” from the belief that “precision” ≡ improvement in sound. I've had (sheepishly) ridiculous arguments with highly opinionated people in this area, and the idea just beggars belief. And it persists.

Its like a religion. Founded on the patterns of tea leaves in teacups.

GoatGuy
 
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