I hate this scale, it says low battery and shuts off after just 3 months of sitting in the drawer. It infuriates me that there’s still a lot of energy in the battery, I can use that in remote controls with no issues
If there’s enough battery to say “low battery”, then there’s enough battery to show the measurements!
I’m bummed that when I had a Thinner bathroom scale, I could weigh myself before and after using the bathroom to see how much I expelled. It was consistent and really useful knowing its precision during keto months (lost up to 3lbs a week). Now I have a Taylor scale that will report the same weight over and over if it’s relatively awake and you change less than 5lbs. So, no thanks to scales that lie.
That’s because of the way these scales work. They use a material that deforms under stress and when it deforms the resistance changes. By putting current through this material and measuring the voltage drop, it can be mapped to how much stress the material is under and thus how much weight is on the scale.
This is a pretty roundabout way and has a lot of caveats, but it is very cheap. So cheap scales always work this way. That’s why they aren’t super accurate and have deviations depending on things like temperature. Another big downside is any permanent deformation ruins the calibration, giving incorrect results. That’s why you never put more weight on kitchen scales than it says, it will break them.
The issue you are running into is the way it measures. It applies a very specific voltage and current in order to get the result. The lookup table it uses is only valid within a narrow range. When the battery voltage goes outside that range, it can no longer perform the measurement. Even though there’s plenty of juice for things like the little processing chip and the LCD display. They don’t need a lot of power and can do with low voltages. But it can no longer weigh anything so it just errors out with a low battery warning.
The GP is not describing a piezoelectric scale. And you won’t be able to find any piezoelectric scale that is anything similar to “cheap”.
You can order 3000 3.3V low drop out (LDO) voltage regulators on LCSC for $25.50. That’s less than a penny each.
For decades scales worked just fine without any electricity. Maybe get one of those.
Normal AA or AAA battery, or a CR<something> button? If it is a button cell, try wiping it with alcohol before you insert it. Many modern button cells have a coating that tastes horrible to prevent people (children) from taking them into the mouth. I’ve noticed that on some brands, this coating measurably increases the resistance of the cell, not only reducing the the power it can deliver, but als making it appear “emptier” than they are ofor the measuring circuits. Wiping off the coating with alcohol (90% isopropanol) expanded the cells’ life (in a kitchen scale to boot!) significantly.
I wonder if this is why my car’s key fob never works well even with fresh batteries
My cheap scale will not work with my freshly recharged amazon basics AAAs. Apparently those do not hold up well enough under load. And of course any set of batteries that does work, discharges over a few months.
So I just bought a cheap mechanical scale (not from Amazon) and I eyeball it for weights under 50g. Good enough and dead reliable.
I know this isn’t helping but your scale is saying “ok lol”
