I just purchased the HDM3055. I infrequently do electronic projects and wanted something to have on my desk instead of my Fluke 179 (the only other DMM that I have really used). I'm a noob. I have no previous experience of a desktop DMM, so I have nothing to compare to. Some first impressions, just on usability, not precision etc., after a day of use:
- It's completely silent. The fan has never started, except on boot when it spins up (so I know the fan is functional). I value this very much and was one reason I bought this particular DMM, since I had understood that it is silent. Now I can leave it on without bothering me.
Some annoying things though:
- You can save preferences and settings, but there is no way I am able to get the button click beeps off after boot. My "man cave" is next to the bedroom, and I don't want it to start beeping when I turn it on late at night while my wife is at sleep. It's a few clicks to get to the menu setting to turn the beeps off, so some beeps are unavoidable AFAIK. If someone knows how to save this setting, please tell me. Other settings are restored though. Feels like a bug.
- The Probe Hold feature would have been useful, but it does not work for my uses in practice. In this mode it is supposed to display the last 8 reading in a table. For example, I wanted to use it when matching resistors for audio projects (especially if you don't have 0.1% resistors at hand). However, it does not record a new reading if the new value is too close to the previous one. For example, measure one resistor at 99.96kΩ. The value is added to the list, good. Let go of the resistor. The infinite value is not recorded, good. Measure the next resistor, 99.98kΩ. The value is not recorded, since it is too close to the previous value. Useless for me. At least add a manual trigger option which works elsewhere, but not in Probe Hold. (When measuring voltages, it does not record the intermediate close-to-zero voltages, which is good, though). Also, the resolution is reduced, and there is no way you can effect this. It would be nice if you could configure the sensitivity for recording new values and the resolution.
- When saving a measurement series to a file, the values are stored in reverse order, i.e. last measurement will be first in the list. Is this normal? So if you were to plot a graph, you'd have to reverse the list first. Why? (I just tested this quickly, so I may be wrong.)
- You can set the date and time on the device. I would have expected it to record the timestamp of the measurements in the file, but it doesn't. Why not? If you want to draw a chart you can't know when the measurement was done. Sure you can set the interval between readings, but that I'd expect that to drift as each reading will not be triggered exactly on that interval, right? I haven't tested though. But still, why not put a timestamp on the readings. What's the clock used for? Just saving the timestamp to the file modification date?
- Clearing the list of samples to be saved is in a completely different menu than where the samples are saved. There is a direct "Acquire" button that goes to saving samples (Save Readings), but if you want to clear the list you have to press Shift, Math, Statistics, Clear Readings (four button presses). The Acquire screen has an empty slot for the context sensitive buttons. Why not put Clear Readings there (as well)? (I tried to insert the attached screenshot here inline, but failed.) Then you go back to Acquire Save, then back to Shift, Math... Small thing maybe, but a PITA, especially since it could have been done better at the same cost without compromising on some other feature. Edit: There is no "shift function" for the Acquire button. They could even have dedicated that to "Clear Readings".
(Save displays "Down writing to file.", should probably be "Done writing to file.").
The display is good/ok. The colors get inverted if you look from above, starting at about a 45 degree angle. I haven't looked from underneath, but I suspect it is the same. From the sides it looks good all the way to 180 degrees. I have some minor backlight issue in the lower left corner. It's mostly visible when you boot it when the screen is black, but you can slightly see it in normal use as a brighter spot. It's not so bad that I would return it in hope of getting a better one, but a little distracting when you start staring at it. I guess most people wouldn't notice it, but I'm a little sensitive to things like this. ;-)
There are no firmware updates available.
There's no manual for the SCPI commands, but I tested a few commands from a Keysight manual, and the ones I tested works. I got the VISA interface working on Linux. I would have hoped to get a simple USB serial interface, but that did not work out of the box, and I don't know how to configure it. If anyone knows, please share.
Despite my rant, I'm happy with my purchase, but then again, I have nothing to compare to. Anyway, it's so much more fun to use than a handheld DMM.