It is pretty easy to come up with 3:
- No Cat rating or CAT ratings that don't reflect needs on a repair bench. The reality is that even rather small servo drives run at 500 VDC sometimes 650 VDC bus voltages. There is enough happening on repair benches that having the higher safety ratings would be of real value.
- No buzzer or one that is effectively silent. Frankly I'd rather see a knob on the front panel for volume adjustment of the buzzer.It would probably be too much to ask for multiple tones for example a high frequency buzz for exceeding the upper limit and a low frequency buzz for the low limit.
- You have to pay way too much to get RTD and thermocouple interfacing.
Other things that drive me crazy in a multimeter. for one they seem to want to replace a scope with some of the functions, Id rather that a multimeter to multimeter things instead of trying to be a scope. For example some multimeters have capacitance functions but why not go a step further and offer more LCR functionality? The same goes for inductors. It should be possible to put some basic LCR functionality, testing up to 100kHz.
Another feature that should be built into a bench meter is a real frequency / counter subsystem with a real BNC input and at least 10 MHz input range, {nothing fancy here}. This should run completely independent of the DVM inputs and frankly with modern silicon should cost a few cents. In a nut shell put some real meat into the "multi".
For the most part modern multimeters have not shrunk much at all compared to a modern scope. So in simple terms modern multimeters need to go on a diet, especially with respect to meter depth . I'd prefer a higher profile to be honest.
Why not a built in programming language like MicroPython or even a Swift implementation. You need a programming langauge that makes it simple to automate tests directly on the meter. This kinda implies a keyboard / mouse input, USB or a decent interface over Ethernet.
Meter handles that don't break!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Add some digital I/O so that you can use MicroPython or Swift to automate your test. Again we have a lot of CPU horsepower available these days, why not do as much as possible locally. Todays meters have some I/O but it is dedicated in most cases. Even if we only have a dozen or so of I/O, it could make for a far more flexible meter.
How about synchronized clock calendars for data time stamping.
Why are these meters battery free. A snap on battery option would be nice for field work, generally calibration. Sometimes a bench meter makes sense in the field. Further even scopes come in battery powered version so why not?
After all these years why are we stuck with one input channel. Two channels that can sample in a synchronized manner, should be a snap with todays tech. Maybe even three. They don't need to be 4 wire capable either.
Finally (I could go on forever), I'd rather see a 4.5 or 5 digit meter that works well and is fast, than to have a bunch of useless digits on the meter. So is this a disadvantage? Well yeah excessive resolution in the meter can be a problem if it creates a high cost device that doesn't support other features that would be nice to have in a meter.