Any fun parts in a salvaged electronic bathroom scale?

Why ask?

If you're going to toss it out anyway, or find one lying on the sidewalk, you might as well take it apart. You're likely to get some parts, just like from any electronic device, and yes, depending on how they are designed, there may be something nifty in there related to converting weight to voltage. Open it up and see. If it does convert weight to voltage (I suppose there are other ways), it might mean a digital meter of some sort. It really depends on what's in there.

Keep in mind that sometimes it's best not to strip down the parts. In some devices, the parts will be very dedicated, and so that IC or this IC may not have much use except as originally used in the device. Once that happens, the parts around it wll be the parts you need to use the IC later, so you might as well keep it intact. For that matter, if the IC is obscure, the peripheral parts may show you how to hook it up.

So if you keep it intact rather than as a source of small parts and maybe that exotic IC, once you find a use for it, you can either use the whole board intact (or cut out the pertinent part of the board) or at the very least trace out the circuit, remove the parts and then build it up again on a smaller circuit board.

That goes for everything. If there's a switching supply, keep it intact (sometimes noting where it came from helps to provide information about the output voltages and currents), because it may be most useful as a switching supply. There may be a time when the parts become more valuable than the full supply, but until that day, keep such things intact and get the ceramic capacitors and generic small signal transistors off something else, like a tv set or VCR.

Michael

Thanks Michael !!

Ivan Vegvary

The one I robbed had a plain glass LCD, a SMD LM324, a "black blob" chip, a piezo-sounder, a watch crystal and a few low spec transistors.

It also had a pressure transducer at each corner - apparently the one used to trigger the chip out of sleep mode had become insensitive.

TBH the most useful bit was the PP3 battery connector.

No it doesn't. For instance, if I say "use the case halves for frisbees" you'll either say "no, no, that's not what I meant!" or "hang on a second, I'm going out to have some fun!"

Many modern one's are a thick plate of toughened glass with the feet/pressure transducers bonded on the corners, the LCD/PCB assy is a module similarly bonded on one edge.

Usually they contain a "zebra strip" to connect the LCD - another item that's often handy to have a spare in the parts drawer.

Thanks everyone. Been saving three old scales. Two are dead and one is intermittent. Gather the LCDs and battery connectors are worthwhile, for sure.

Ivan Vegvary