<![CDATA[Oh right @Njord insisted I tell you, fedi, about this button.]]>Oh right @Njord insisted I tell you, fedi, about this button. It's a big orange button (AC remote for scale) that toggles an extension cord's power on/off when pushed

So far so boring right? Well it had been acting up a bit so we opened it up to change the battery and... no battery?

It apparently uses the mechanical force of pushing the button (it requires a bit of a push!) to trigger a piezoelectric charge which is apparently enough to send a wireless signal to the receiver

Neat!

]]>https://forum.fedi.dk/topic/7bc2cea1-2422-46a3-bf7b-fbaef1c7018b/oh-right-@njord-insisted-i-tell-you-fedi-about-this-button.RSS for NodeSun, 31 May 2026 12:33:33 GMTSat, 30 May 2026 19:08:46 GMT60<![CDATA[Reply to Oh right @Njord insisted I tell you, fedi, about this button. on Sat, 30 May 2026 21:01:00 GMT]]>@oblomov @Njord yeah I guess? It's years old at this point

]]>https://forum.fedi.dk/post/https://mastodon.gamedev.place/users/eniko/statuses/116665539655767043https://forum.fedi.dk/post/https://mastodon.gamedev.place/users/eniko/statuses/116665539655767043Sat, 30 May 2026 21:01:00 GMT<![CDATA[Reply to Oh right @Njord insisted I tell you, fedi, about this button. on Sat, 30 May 2026 20:59:20 GMT]]>@LunaDragofelis @dequbed @eniko @Njord

You can receive free electrons off of glucose through enzymatic breakdown similar than the body does - although the body stores it chemically in ATP or others.

It is however currently no longterm solution since the enzymes break down over time.

]]>https://forum.fedi.dk/post/https://hessen.social/users/FK_Med/statuses/116665533113409584https://forum.fedi.dk/post/https://hessen.social/users/FK_Med/statuses/116665533113409584Sat, 30 May 2026 20:59:20 GMT<![CDATA[Reply to Oh right @Njord insisted I tell you, fedi, about this button. on Sat, 30 May 2026 20:57:49 GMT]]>@eniko @Njord reading this has brought me the same joy as when I learnt that the circuitry inside NFC cards is powered by the electromagnetic current that sends the data

]]>https://forum.fedi.dk/post/https://mastodon.social/users/frikinin/statuses/116665527116813439https://forum.fedi.dk/post/https://mastodon.social/users/frikinin/statuses/116665527116813439Sat, 30 May 2026 20:57:49 GMT<![CDATA[Reply to Oh right @Njord insisted I tell you, fedi, about this button. on Sat, 30 May 2026 20:56:15 GMT]]>@eniko @Njord
Enocean is a conglomerate of smarthome appliances purely designed with energy harvesting. No changing batterys ever.

Unfortunately it is rather expensive and more difficult to integrate.

]]>https://forum.fedi.dk/post/https://hessen.social/users/FK_Med/statuses/116665521012218096https://forum.fedi.dk/post/https://hessen.social/users/FK_Med/statuses/116665521012218096Sat, 30 May 2026 20:56:15 GMT<![CDATA[Reply to Oh right @Njord insisted I tell you, fedi, about this button. on Sat, 30 May 2026 20:51:38 GMT]]>@eniko

German CASO has several models of battery free kitchen scales (as an idea, maybe other brands are available locally):
https://caso-design.de/de/p/caso-kitchen-energy-design-kuechenwaage-mit-kitchen-energy-technologie/
(via the menu you can change region to UK - while selecting Benelux doesn't seem to work)

]]>https://forum.fedi.dk/post/https://mstdn.social/users/stekopf/statuses/116665502818787837https://forum.fedi.dk/post/https://mstdn.social/users/stekopf/statuses/116665502818787837Sat, 30 May 2026 20:51:38 GMT<![CDATA[Reply to Oh right @Njord insisted I tell you, fedi, about this button. on Sat, 30 May 2026 20:47:21 GMT]]>@eniko @Njord I have a button like this too. Feels like magic!

]]>https://forum.fedi.dk/post/https://framapiaf.org/users/borisschapira/statuses/116665485999212752https://forum.fedi.dk/post/https://framapiaf.org/users/borisschapira/statuses/116665485999212752Sat, 30 May 2026 20:47:21 GMT<![CDATA[Reply to Oh right @Njord insisted I tell you, fedi, about this button. on Sat, 30 May 2026 20:46:18 GMT]]>@CppGuy @sinbad @eniko @Njord
I've added mains and/or rechargeable to many battery things starting with a VFD calculator.

Now all the non-heating/cooking stuff is on a Solar & Grid charged UPS. 12 main panels and about 14 kWh of LiFePO4 batteries.
No more annual PC UPS battery replacement.

]]>https://forum.fedi.dk/post/https://mastodon.ie/users/raymaccarthy/statuses/116665481831483100https://forum.fedi.dk/post/https://mastodon.ie/users/raymaccarthy/statuses/116665481831483100Sat, 30 May 2026 20:46:18 GMT<![CDATA[Reply to Oh right @Njord insisted I tell you, fedi, about this button. on Sat, 30 May 2026 20:40:25 GMT]]>@eniko @Njord that's really cool!

So why isn't working as well now? Piezoelectric crystal got consumed or something?

]]>https://forum.fedi.dk/post/https://sociale.network/users/oblomov/statuses/116665458701503864https://forum.fedi.dk/post/https://sociale.network/users/oblomov/statuses/116665458701503864Sat, 30 May 2026 20:40:25 GMT<![CDATA[Reply to Oh right @Njord insisted I tell you, fedi, about this button. on Sat, 30 May 2026 20:38:10 GMT]]>@raymaccarthy @sinbad @eniko @Njord

We had kinda the opposite in our last house. The button-push was wired to a battery-powered bell box, but the builders had put the bell and the battery directly above a radiator, which meant that we had to change the batteries every six weeks or so, because batteries don't like heat. We eventually gave up on it and installed something mains-powered.

]]>https://forum.fedi.dk/post/https://infosec.space/users/CppGuy/statuses/116665449897560686https://forum.fedi.dk/post/https://infosec.space/users/CppGuy/statuses/116665449897560686Sat, 30 May 2026 20:38:10 GMT<![CDATA[Reply to Oh right @Njord insisted I tell you, fedi, about this button. on Sat, 30 May 2026 20:32:57 GMT]]>@eniko @Njord BTW the Brazilian product page says there's a fuse which can trip if current exceeds 10 A, but the fuse should be resettable

]]>https://forum.fedi.dk/post/https://bertha.social/ap/users/116054147328405917/statuses/116665429362836068https://forum.fedi.dk/post/https://bertha.social/ap/users/116054147328405917/statuses/116665429362836068Sat, 30 May 2026 20:32:57 GMT<![CDATA[Reply to Oh right @Njord insisted I tell you, fedi, about this button. on Sat, 30 May 2026 20:23:44 GMT]]>@leonardof I'm not sure but @Njord might be able to tell you

]]>https://forum.fedi.dk/post/https://mastodon.gamedev.place/users/eniko/statuses/116665393096158803https://forum.fedi.dk/post/https://mastodon.gamedev.place/users/eniko/statuses/116665393096158803Sat, 30 May 2026 20:23:44 GMT<![CDATA[Reply to Oh right @Njord insisted I tell you, fedi, about this button. on Sat, 30 May 2026 20:18:19 GMT]]>@eniko @Njord ELG PowerCube/PowerRemote?

]]>https://forum.fedi.dk/post/https://bertha.social/ap/users/116054147328405917/statuses/116665371815076191https://forum.fedi.dk/post/https://bertha.social/ap/users/116054147328405917/statuses/116665371815076191Sat, 30 May 2026 20:18:19 GMT<![CDATA[Reply to Oh right @Njord insisted I tell you, fedi, about this button. on Sat, 30 May 2026 20:06:17 GMT]]>@sinbad @eniko @Njord
I got fed up with batteries in door bell button and the "bell" and unreliability (433 MHz).
Eventually I found a real wired pushbutton and BingBong inside box, though that used batteries. So I added a transformer to 8V AC at the fuse box, because the bing-bong real solenoid doesn't care about AC or DC. The bulb in the door bell button is across the switch, so in series & glows orange, thus long life.

1950s technology, but 100% reliable.

No spying to Amazon.

]]>https://forum.fedi.dk/post/https://mastodon.ie/users/raymaccarthy/statuses/116665324476970134https://forum.fedi.dk/post/https://mastodon.ie/users/raymaccarthy/statuses/116665324476970134Sat, 30 May 2026 20:06:17 GMT<![CDATA[Reply to Oh right @Njord insisted I tell you, fedi, about this button. on Sat, 30 May 2026 20:04:38 GMT]]>@eniko @Njord speaking on behalf of the fediverse: yes, we like this

]]>https://forum.fedi.dk/post/https://notnull.space/users/paul/statuses/01KSX7T5RZ15GW23554KSSG25Mhttps://forum.fedi.dk/post/https://notnull.space/users/paul/statuses/01KSX7T5RZ15GW23554KSSG25MSat, 30 May 2026 20:04:38 GMT<![CDATA[Reply to Oh right @Njord insisted I tell you, fedi, about this button. on Sat, 30 May 2026 20:00:29 GMT]]>I got light switches like that in my house for nearly ten years. Sometimes you have to push them several times if you haven't used them in a while, probably to get enough piezo charge for a signal.

https://kinetic-switch.de/en

]]>https://forum.fedi.dk/post/https://mastodon.online/users/oliver_schafeld/statuses/116665301674204407https://forum.fedi.dk/post/https://mastodon.online/users/oliver_schafeld/statuses/116665301674204407Sat, 30 May 2026 20:00:29 GMT<![CDATA[Reply to Oh right @Njord insisted I tell you, fedi, about this button. on Sat, 30 May 2026 19:59:25 GMT]]>@eniko @Njord My previous workplace had a battery-free wireless doorbell - this must be how that worked too. Not as cool as a big friendly button, though!

]]>https://forum.fedi.dk/post/https://dosgame.club/users/lunarloony/statuses/116665297471783786https://forum.fedi.dk/post/https://dosgame.club/users/lunarloony/statuses/116665297471783786Sat, 30 May 2026 19:59:25 GMT<![CDATA[Reply to Oh right @Njord insisted I tell you, fedi, about this button. on Sat, 30 May 2026 19:53:12 GMT]]>@eniko @Njord ARM has ultra low-power CPUs that can run off energy harvesting, itโ€™s honestly amazing how little power you need for modern devices and it kinda feels like magicโ€ฆ

]]>https://forum.fedi.dk/post/https://mastodon.gamedev.place/users/btsherratt/statuses/116665273062694324https://forum.fedi.dk/post/https://mastodon.gamedev.place/users/btsherratt/statuses/116665273062694324Sat, 30 May 2026 19:53:12 GMT<![CDATA[Reply to Oh right @Njord insisted I tell you, fedi, about this button. on Sat, 30 May 2026 19:53:08 GMT]]>@eniko @Njord they should make those also for foot activation, would be more accessible too if used as a doorbell

]]>https://forum.fedi.dk/post/https://hachyderm.io/users/janet_catcus/statuses/116665272773459678https://forum.fedi.dk/post/https://hachyderm.io/users/janet_catcus/statuses/116665272773459678Sat, 30 May 2026 19:53:08 GMT<![CDATA[Reply to Oh right @Njord insisted I tell you, fedi, about this button. on Sat, 30 May 2026 19:48:59 GMT]]>@eniko @Njord I have a doorbell like that! The issue is that since it requires some effort in pushing, some people think it's just touch activated and don't really ring it ๐Ÿ™‚

]]>https://forum.fedi.dk/post/https://mastodon.social/users/davidadriao/statuses/116665256451719989https://forum.fedi.dk/post/https://mastodon.social/users/davidadriao/statuses/116665256451719989Sat, 30 May 2026 19:48:59 GMT<![CDATA[Reply to Oh right @Njord insisted I tell you, fedi, about this button. on Sat, 30 May 2026 19:44:07 GMT]]>@eniko @Njord Early TV remote controls (1960s) were similar. Each button triggered a spring to hit an ultrasonic tuning fork which the TV could identify.

My childhood experiments indicated a range of 10 - 20 feet (~ 3 - 6 meters).

]]>https://forum.fedi.dk/post/https://gardenstate.social/users/AverageJoe/statuses/116665237309480477https://forum.fedi.dk/post/https://gardenstate.social/users/AverageJoe/statuses/116665237309480477Sat, 30 May 2026 19:44:07 GMT<![CDATA[Reply to Oh right @Njord insisted I tell you, fedi, about this button. on Sat, 30 May 2026 19:43:59 GMT]]>@LunaDragofelis @eniko @Njord yes, but not the kind of power you need for prosthetics, more like picoampere. There's a lot of extremely fundamental research that would still be needed for the kind of application you're thinking of ^^'

]]>https://forum.fedi.dk/post/https://mastodon.chaosfield.at/users/dequbed/statuses/116665236843538262https://forum.fedi.dk/post/https://mastodon.chaosfield.at/users/dequbed/statuses/116665236843538262Sat, 30 May 2026 19:43:59 GMT<![CDATA[Reply to Oh right @Njord insisted I tell you, fedi, about this button. on Sat, 30 May 2026 19:34:55 GMT]]>@dianea @Njord neat!

]]>https://forum.fedi.dk/post/https://mastodon.gamedev.place/users/eniko/statuses/116665201187752295https://forum.fedi.dk/post/https://mastodon.gamedev.place/users/eniko/statuses/116665201187752295Sat, 30 May 2026 19:34:55 GMT<![CDATA[Reply to Oh right @Njord insisted I tell you, fedi, about this button. on Sat, 30 May 2026 19:34:10 GMT]]>@rotopenguin I've *never* heard of these! Thanks ๐Ÿ˜Š
Interesting to see the wide variety of coherers.

]]>https://forum.fedi.dk/post/https://ottawa.place/users/MichaelPorter/statuses/116665198219053401https://forum.fedi.dk/post/https://ottawa.place/users/MichaelPorter/statuses/116665198219053401Sat, 30 May 2026 19:34:10 GMT<![CDATA[Reply to Oh right @Njord insisted I tell you, fedi, about this button. on Sat, 30 May 2026 19:29:03 GMT]]>@eniko @Njord

I remember the old television remote controls had several ultrasonic whistles that pushing a button would be picked up in the television's vacuum tube amplifier and activate solenoids to mechanically change channels or rotate the volume knob...

]]>https://forum.fedi.dk/post/https://lgbtqia.space/users/dianea/statuses/116665178124687069https://forum.fedi.dk/post/https://lgbtqia.space/users/dianea/statuses/116665178124687069Sat, 30 May 2026 19:29:03 GMT