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DarkRange55
Enlightened
- Oct 15, 2023
- 1,684
![IMG 4159 IMG 4159](https://i.sanctioned-suicide.net/images/2024/08/thumb/206697_IMG_4159.jpeg)
These are still required in US buildings. It's a very, very old technology and is very vulnerable to compromise. Any kind of ground fault or anything kills it. I've seen this entire system downed in a building because of a gum wrapper. Not joke. The circuits are all wired in parallel. Sound Powered Phones which is what ships in WW2 used. They operate on magnetostrsiction.
Quartz crystals exhibit piezoelectric properties, meaning they can generate an electric charge in response to applied mechanical stress (such as vibration). In some parts a building, radios and phones aren't always reliable. Its a backup communication system for firefighters
![Fire engine :fire_engine: 🚒](https://cdn.jsdelivr.net/joypixels/assets/8.0/png/unicode/64/1f692.png)
![en.wikipedia.org](/proxy.php?image=https%3A%2F%2Fupload.wikimedia.org%2Fwikipedia%2Fcommons%2F5%2F51%2FHMNZS_Te_Kaha_sound-powered_telephone_20080702.jpg&hash=acd40291fe859875d54270ff2a5524ed&return_error=1)