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Re: Error of % + digits?

From Cydrome Leader <presence@MUNGEpanix.com>
Newsgroups sci.electronics.equipment, sci.electronics.basics
Subject Re: Error of % + digits?
Date 2020-06-26 04:54 +0000
Organization PANIX Public Access Internet and UNIX, NYC
Message-ID <rd3v1r$egj$1@reader1.panix.com> (permalink)
References (8 earlier) <op.0mhd5c1iwdg98l@glass> <KaiHG.15698$qj7.139@fx04.ams1> <op.0miefkhkwdg98l@glass> <MPG.3957f41475277903989f21@news.east.earthlink.net> <op.0mipcac3wdg98l@glass>

Cross-posted to 2 groups.

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In sci.electronics.equipment Commander Kinsey <CFKinsey@military.org.jp> wrote:
> On Sat, 20 Jun 2020 16:24:41 +0100, Ralph Mowery <rmowery28146@earthlink.net> wrote:
> 
>> In article <op.0miefkhkwdg98l@glass>, CFKinsey@military.org.jp says...
>>>
>>> I'd need to contract OCD to understand that.  There's only one thing in question here, how close is the reading to the correct value.  You can't split that into two.  3.1416 is better than 3.14, and that's it.  All you can state with a reading is it's correct to within a certain percentage.
>>
>> Try this.
>>
>> A doctor does a very complicated operation on your left arm like a joint
>> replacement.  It all goes very well.  Very precise.
>>
>> However he should have done the operation on the right arm that was
>> causing trouble.  Not accurate.
> 
> Nope, because the first one is 100% useless.  I wouldn't call that precise at all, as he was out by half a metre.
> 
>> That is why a voltmeter can show 3 digits and be accurate to only the
>> last digit being in question by one number either way, but a 5 digit
>> volt meter can show many numbers, but if it is not calibrated corrctly
>> the 2nd digit to the 5 th digit  could be way off and the meter not
>> accurate at all.
> 
> Showing those extra two numbers is pointless if they're wrong.  All that matters is how many volts difference between the actual voltage and what is shown.

agreed. The problem with the bullets and the target story is that when 
explained, we somehow perfectly know where the bullets are- be in on 
target or a small grouping somewhere else. Cheapo meters won't give 
CONSISTENT or REPEATABLE results, not matter how "precise" they pretended 
to be, or how accurate the spec sheet claims, especially considering the 
last digit(s) may be totaly wrong, and random. It's like having crappy or 
dirty test leads or a component. You'll get all the digits in the world, 
but they keep changing. You won't even be able to pick a reading.

Keep in mind that "calibrated" equipment doesn't even have to be precise 
or accurate. An example would be an adjustable power supply with digital 
readout. Say it's always reads high by 0.7 volts. It's not precise or 
accurate, but by knowing the offset it can used with success and may even 
have great regulation.

On the other hand say you have an alibaba special power supply that's 
"accurate" to +/- 0.35 volts, with terrible regulation that oscillates.

What power supply is better?

So the point is cheapo equipment can have lots of bogus digits and 
readings that flop up and down, while better equipment can be more 
consistently wrong, which can be compensated for. Precision and accuracy 
mean little by themselves if you need multiple readings.

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Thread

Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-06-18 14:03 +0100
  Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-06-18 14:28 +0100
  Re: Error of % + digits? Pimpom <nobody@nowhere.com> - 2020-06-18 20:08 +0530
    Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-06-18 15:41 +0100
      Re: Error of % + digits? Ralph Mowery <rmowery28146@earthlink.net> - 2020-06-18 18:16 -0400
        Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-06-18 23:48 +0100
          Re: Error of % + digits? Ralph Mowery <rmowery28146@earthlink.net> - 2020-06-18 19:38 -0400
            Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-06-19 21:46 +0100
              Re: Error of % + digits? Ralph Mowery <rmowery28146@earthlink.net> - 2020-06-19 18:55 -0400
                Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-06-19 23:59 +0100
                Re: Error of % + digits? Pimpom <nobody@nowhere.com> - 2020-06-20 12:09 +0530
                Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-06-20 13:03 +0100
                Re: Error of % + digits? Ralph Mowery <rmowery28146@earthlink.net> - 2020-06-20 11:24 -0400
                Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-06-20 16:58 +0100
                Re: Error of % + digits? Pimpom <nobody@nowhere.com> - 2020-06-20 23:28 +0530
                Re: Error of % + digits? Ralph Mowery <rmowery28146@earthlink.net> - 2020-06-20 14:15 -0400
                Re: Error of % + digits? Tom Gardner <spamjunk@blueyonder.co.uk> - 2020-06-20 23:54 +0100
                Re: Error of % + digits? Cydrome Leader <presence@MUNGEpanix.com> - 2020-06-26 05:10 +0000
                Re: Error of % + digits? Ralph Mowery <rmowery28146@earthlink.net> - 2020-06-26 11:27 -0400
                Re: Error of % + digits? Cydrome Leader <presence@MUNGEpanix.com> - 2020-06-27 06:40 +0000
                Re: Error of % + digits? Ralph Mowery <rmowery28146@earthlink.net> - 2020-06-27 09:55 -0400
                Re: Error of % + digits? Cydrome Leader <presence@MUNGEpanix.com> - 2020-06-29 02:59 +0000
                Re: Error of % + digits? Ralph Mowery <rmowery28146@earthlink.net> - 2020-06-29 10:54 -0400
                Re: Error of % + digits? Cydrome Leader <presence@MUNGEpanix.com> - 2020-06-30 03:28 +0000
                Re: Error of % + digits? Jeroen Belleman <jeroen@nospam.please> - 2020-06-20 20:18 +0200
                Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-06-24 18:37 +0100
                Re: Error of % + digits? Cydrome Leader <presence@MUNGEpanix.com> - 2020-06-26 04:54 +0000
                Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-11 21:38 +0100
                Re: Error of % + digits? Cydrome Leader <presence@MUNGEpanix.com> - 2020-07-13 03:21 +0000
                Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-13 13:32 +0100
                Re: Error of % + digits? Cydrome Leader <presence@MUNGEpanix.com> - 2020-06-26 04:23 +0000
                Re: Error of % + digits? Pimpom <nobody@nowhere.com> - 2020-06-26 14:02 +0530
                Re: Error of % + digits? Cydrome Leader <presence@MUNGEpanix.com> - 2020-06-27 06:56 +0000
                Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-12 18:45 +0100
                Re: Error of % + digits? Pimpom <nobody@nowhere.com> - 2020-07-12 23:31 +0530
                Re: Error of % + digits? Tom Gardner <spamjunk@blueyonder.co.uk> - 2020-07-12 20:21 +0100
                Re: Error of % + digits? Pimpom <nobody@nowhere.com> - 2020-07-13 10:23 +0530
                Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-13 13:36 +0100
                Re: Error of % + digits? Pimpom <nobody@nowhere.com> - 2020-07-13 20:57 +0530
                Re: Error of % + digits? Jeroen Belleman <jeroen@nospam.please> - 2020-07-13 17:39 +0200
                Re: Error of % + digits? Tom Gardner <spamjunk@blueyonder.co.uk> - 2020-07-13 21:04 +0100
                Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-20 21:35 +0100
                Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-20 21:36 +0100
                Re: Error of % + digits? Pimpom <nobody@nowhere.com> - 2020-07-21 12:05 +0530
                Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-31 23:53 +0100
                Re: Error of % + digits? Pimpom <nobody@nowhere.com> - 2020-08-01 14:31 +0530
                Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-13 13:35 +0100
                Re: Error of % + digits? Cydrome Leader <presence@MUNGEpanix.com> - 2020-07-16 07:30 +0000
                Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-17 00:19 +0100
                Re: Error of % + digits? Cydrome Leader <presence@MUNGEpanix.com> - 2020-07-21 01:13 +0000
                Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-08-04 22:27 +0100
                Re: Error of % + digits? Cydrome Leader <presence@MUNGEpanix.com> - 2020-09-09 07:39 +0000
                Re: Error of % + digits? Jasen Betts <jasen@xnet.co.nz> - 2020-07-17 12:15 +0000
                Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-28 19:02 +0100
                Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-13 13:38 +0100
      Re: Error of % + digits? Rich <rich@example.invalid> - 2020-06-24 20:06 +0000
        Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-06-30 00:41 +0100
          Re: Error of % + digits? Cydrome Leader <presence@MUNGEpanix.com> - 2020-06-30 03:52 +0000
            Re: Error of % + digits? Ralph Mowery <rmowery28146@earthlink.net> - 2020-06-30 11:09 -0400
              Re: Error of % + digits? Cydrome Leader <presence@MUNGEpanix.com> - 2020-07-02 05:45 +0000
                Re: Error of % + digits? Jasen Betts <jasen@xnet.co.nz> - 2020-07-02 07:03 +0000
                Re: Error of % + digits? Ralph Mowery <rmowery28146@earthlink.net> - 2020-07-02 10:41 -0400
                Re: Error of % + digits? RheillyPhoull <Rheilly@bigslong.com> - 2020-07-03 09:20 +0800
                Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-16 20:09 +0100
                Re: Separate amps jacks on multimeters Rich <rich@example.invalid> - 2020-07-17 14:02 +0000
                Re: Separate amps jacks on multimeters "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-17 19:16 +0100
                Re: Separate amps jacks on multimeters Rich <rich@example.invalid> - 2020-07-17 20:26 +0000
                Re: Separate amps jacks on multimeters "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-17 21:44 +0100
                Re: Separate amps jacks on multimeters Rich <rich@example.invalid> - 2020-07-17 22:37 +0000
                Re: Separate amps jacks on multimeters "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-18 00:11 +0100
                Re: Separate amps jacks on multimeters Ralph Mowery <rmowery28146@earthlink.net> - 2020-07-17 18:07 -0400
                Re: Separate amps jacks on multimeters "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-17 23:31 +0100
                Re: Separate amps jacks on multimeters Ralph Mowery <rmowery28146@earthlink.net> - 2020-07-17 19:10 -0400
                Re: Separate amps jacks on multimeters "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-18 00:18 +0100
                Re: Separate amps jacks on multimeters Ralph Mowery <rmowery28146@earthlink.net> - 2020-07-17 19:30 -0400
                Re: Separate amps jacks on multimeters "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-28 22:16 +0100
                Re: Separate amps jacks on multimeters Cydrome Leader <presence@MUNGEpanix.com> - 2020-07-22 04:24 +0000
                Re: Separate amps jacks on multimeters Ralph Mowery <rmowery28146@earthlink.net> - 2020-07-22 12:28 -0400
                Re: Separate amps jacks on multimeters Ralph Mowery <rmowery28146@earthlink.net> - 2020-07-17 19:25 -0400
                Re: Separate amps jacks on multimeters Cydrome Leader <presence@MUNGEpanix.com> - 2020-07-22 04:20 +0000
                Re: Separate amps jacks on multimeters Ralph Mowery <rmowery28146@earthlink.net> - 2020-07-22 12:23 -0400
                Re: Error of % + digits? Jasen Betts <jasen@xnet.co.nz> - 2020-07-03 13:10 +0000
                Re: Error of % + digits? Ralph Mowery <rmowery28146@earthlink.net> - 2020-07-03 10:14 -0400
                Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-16 20:10 +0100
                Re: Error of % + digits? Ralph Mowery <rmowery28146@earthlink.net> - 2020-07-16 16:03 -0400
                Re: Error of % + digits? Michael Terrell <terrell.michael.a@gmail.com> - 2020-07-16 13:13 -0700
                Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-17 00:02 +0100
                Re: Error of % + digits? Ralph Mowery <rmowery28146@earthlink.net> - 2020-07-16 23:29 -0400
                Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-24 22:09 +0100
                Re: Error of % + digits? Rich <rich@example.invalid> - 2020-07-24 22:58 +0000
                Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-25 00:31 +0100
                Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-17 00:01 +0100
                Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-16 18:51 +0100
                Re: Error of % + digits? Cydrome Leader <presence@MUNGEpanix.com> - 2020-07-26 03:53 +0000
              Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-16 18:45 +0100
                Re: Error of % + digits? Ralph Mowery <rmowery28146@earthlink.net> - 2020-07-16 15:53 -0400
            Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-16 18:46 +0100
              Re: Error of % + digits? Michael Terrell <terrell.michael.a@gmail.com> - 2020-07-16 10:54 -0700
                Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-17 00:15 +0100
              Re: Error of % + digits? Cydrome Leader <presence@MUNGEpanix.com> - 2020-07-26 04:17 +0000
          Re: Error of % + digits? Rich <rich@example.invalid> - 2020-06-30 07:59 +0000
  Re: Error of % + digits? Dieter Michel <dmichel@prosound.de> - 2020-06-22 17:19 +0200
  Re: Error of % + digits? Rich <rich@example.invalid> - 2020-06-24 20:03 +0000

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