jim77742@gmail.com said:

The probes can be as important as the meter.

The typical Fluke handheld comes with probes that are safe for working around
wall power.  There is probably some official spec.  The cables are happy at
600 volts or something in that range.  The Amp mode has a fuse.  ...  All good
stuff, but probably not interesting when running in time-nut mode.

If I'm trying to measure a voltage on a board full of modern electronics, I
want sharp, tiny tips on the probes.

--
These are my opinions.  I hate spam.

jim77742@gmail.com said:

testing the linearity of a 24 bit DAC.

For the former, I find a built-in clamp type AC/DC ammeter with a
reasonably sensitive range (40 A or less) is very handy. My current
favorite is the Mastech MS2108, from Amazon.

-Jim Harman

Hi

Also depends a bit on why you are shopping. If the answer is “lost the second one this year”
then the debate over holding calibration likely isn’t of much relevance. If the answer is that the
nixie tubes in the prior unit finally got to dim to read …. not quite the same issue.

Bob

I have a cheap Chinese clamp-on power line ammeter I use occasionally.  Its lowest range is 20 A I think but I built a 10:1 expander (very simple).  I also built a line separator so I can grip just one line.
Bob
On Saturday, March 23, 2019, 5:00:23 PM PDT, Jim Harman j99harman@gmail.com wrote:

jim77742@gmail.com said:

testing the linearity of a 24 bit DAC.

For the former, I find a built-in clamp type AC/DC ammeter with a
reasonably sensitive range (40 A or less) is very handy. My current
favorite is the Mastech MS2108, from Amazon.

-Jim Harman

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Hi All,

Thanks so much everyone for your comments. I especially liked "get the
orange one". Because that's what I did get (I think it's orange - could be
yellow).

I was deliberately vague (apologies) but I just wanted a broad response.
Which I got.

I've settled on the Fluke 87V. It's on it's way.

Jim

On Sun, 24 Mar 2019 at 12:00, Bob Albert via time-nuts <
time-nuts@lists.febo.com> wrote:

Fluke is the yellow one. Agilent is the orange one. Both are excellent. You
made a fine choice.

On Sunday, March 24, 2019, Jim Palfreyman jim77742@gmail.com wrote:

--

I have a comment regarding "classic equipment." About 20 years ago I
got an HP 410B VTVM, was pleasantly surprised that it still appeared
to be within the stated accuracy, but was astounded to find the
short-circuit current (measured the current range on a modern DMM) on
the 1-ohm scale was 100mA. This is from memory from back then, so I
should double-check it, but it was still a lot.

This brings to mind the importance of knowing the ins and outs of
equipment, and that you may not want to, for example, check the
polarity of a sensitive transistor with this unit's resistance scale.

On Sun, Mar 24, 2019 at 12:11 PM William H. Fite omniryx@gmail.com wrote:

That is not unusual.  Back then, all VOMs and most VTVMs pumped substantial current through the unknown.  When I became aware of that I started paying closer attention to how measurements were made.
In general, 100 mA is typical short circuit current on low Ohms range.  Some, such as the Triplett 630, go even higher.  (I suggest you measure the short circuit current on low Ohms range on your most-used meter before you burn out somehting.)
So you are right to caution people to avoid thinking of test gear as magic boxes.
Another thing that came to my attention is the fact that the current through the unknown will be different for different values ot the unkown.  Not so much a factor with the 410B, but most VOMs rely on batteries and the terminal voltage will change as the unknown value changes, making the calibration poor for low resistance.
For instance, if center scale is 15 Ohms and you short the leads to zero the meter, then measure a 15 Ohm resistor, it will read less than 15 Ohms due to the slight increase in battery voltage at half current.  It gets worse as the battery ages and for higher resistance on that range.  The crowding of calibration at the high resistance end of the scale should not be an invitation to estimate high resistance either, since the mechanical meter zero becomes a factor.  Pointer 'stiction' can cause errors as well.
Bob
On Sunday, March 24, 2019, 5:01:49 PM PDT, Ben Bradley ben.pi.bradley@gmail.com wrote:

I have a comment regarding "classic equipment." About 20 years ago I
got an HP 410B VTVM, was pleasantly surprised that it still appeared
to be within the stated accuracy, but was astounded to find the
short-circuit current (measured the current range on a modern DMM) on
the 1-ohm scale was 100mA. This is from memory from back then, so I
should double-check it, but it was still a lot.

This brings to mind the importance of knowing the ins and outs of
equipment, and that you may not want to, for example, check the
polarity of a sensitive transistor with this unit's resistance scale.

On Sun, Mar 24, 2019 at 12:11 PM William H. Fite omniryx@gmail.com wrote:

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