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What's the point of hold or auto-hold in DMMs? Ever seen a properly working one?
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bdunham7:

--- Quote from: RoGeorge on April 21, 2023, 02:31:37 pm ---Thank you.  Mine holds the number after it beeps, but only until the next measurement differs more than 100 units.  That's written in the mtx3283 user manual:

So, mine is faulty by design.   >:(

--- End quote ---

If they include zero/open as a stable measurement that differs by more than 100 counts and thus replaces the old reading, then yes I'd say it was pretty useless...
...but are you sure that is the case?  Will a 0.000V (or close) reading actually cause the old reading to disappear?  Or is it downranging and then reading noise?  Can you try manual ranging?
AVGresponding:

--- Quote from: RoGeorge on April 21, 2023, 02:31:37 pm ---
--- Quote from: bdunham7 on April 21, 2023, 02:07:09 pm ---I set a power supply to 3.00V and set the meter for AUTOHOLD.  I touch the probes, the meter beeps and displays 3.0xx volts.  I remove the probes and the display stays at 3.0xx volts, presumably forever.
--- End quote ---

Thank you.  Mine holds the number after it beeps, but only until the next measurement differs more than 100 units.  That's written in the mtx3283 user manual:

--- Quote ---AUTO HOLD mode automatically freezes on the screen the current main
measurement whenever a stable measurement is detected. It is confirmed
by a beep (unless the configuration "Beep no" has been selected in the
Configuration menu).
The values memorized remain displayed until the next stable measurement
taken (measurement different from ± 100 digits) or until deactivation of AUTO
HOLD mode.
--- End quote ---

So, mine is faulty by design.   >:(

--- End quote ---

Can you change the settings? I've just been playing with my bench meters and while the 34401A and TTi 1906 both work pretty well like the handhelds, the K2000 and K2015 are a bit finicky to set up; you can adjust the % at which it triggers a new reading and also the number of counts, and the measurement rate also has a big impact, on fast it holds for less than a second, but on slow it holds pretty much indefinitely.
RoGeorge:
mtx3283 is a handheld DMM, not a bench DMM, auto-hold is described at page 18 in the user manual and it has no extra settings:  https://www.aemc.com/userfiles/files/resources/usermanuals/Multimeters/MTX_3281-3282-3283_EN.pdf



--- Quote from: bdunham7 on April 21, 2023, 02:40:31 pm ---Will a 0.000V (or close) reading actually cause the old reading to disappear?  Or is it downranging and then reading noise?  Can you try manual ranging?
--- End quote ---

That's what I'm complaining about.  Either manual or autorange, my mtx3283 does the same.

For example: 
- set manual ranging, DC 10.0000V full scale, Auto-Hold, measure a NiMH 6 cells battery
- it beeps once when it reaches a stable measurement:  +7.7882V
- after disconnecting the probes, the display changes almost instantly (100 counts means 1.0mV on this range)
- but it doesn't beep yet
- then about half a second later, after the display changed about 3 times (without any beep),
- it sees again a stable enough value, and it beeps and shows:  +0.0029V while I keep the probes in the air
bdunham7:
That sounds like a legitimate complaint.  Whoever programmed that perhaps just didn't fully understand the concept!  It sounds like the sort of thing that would merit a firmware update if that is possible.
RoGeorge:
I've looked for FW updates and couldn't find any on the producer's site (Chauvin-Arnaux).  My understanding is this line of instruments are made with a proprietary ASIC.  I suspect that probably the bug is in the ASIC chip, thus not fixable.  I doubt that after so many years nobody noticed and no FW update was released.

Could be, as well, that I have a defective mtx3283, while other mtx3283 are working just as expected.  :-//
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