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ELT Batteries help.

Both my Apple Watch and iPhone have crash detection which will automatically send to satellite if a cellular or wifi connection aren't available if the device sees that I'm immobile for some period of time. I crashed my mountain bike last summer but was up and moving so the watch just asked me if I was OK. If I hadn't responded, it would have dialed 911 and I'd have some 'splainin' to do...
Emergency crash detection doesn't use satellites, only cellular. iPhone's satellite connectivity requires you to follow on-screen directions to point at the satellites which can't happen automatically.
Garmin inReach has a chunky antenna which doesn't need this kind of orientation (it just needs a view of the sky), but doesn't detect crashes.
 
Emergency crash detection doesn't use satellites, only cellular. iPhone's satellite connectivity requires you to follow on-screen directions to point at the satellites which can't happen automatically.
Garmin inReach has a chunky antenna which doesn't need this kind of orientation (it just needs a view of the sky), but doesn't detect crashes.
I've never had to try it, but... https://support.apple.com/en-us/HT213426

If your iPhone or Apple Watch detects a severe car crash or a hard fall and you're unresponsive, an automatic Crash Detection or Fall Detection notification to emergency services may be communicated by your iPhone 14, iPhone 14 Pro, iPhone 15, or iPhone 15 Pro using Emergency SOS via satellite if you're outside of cellular and Wi-Fi coverage.
 
In this thread I've seen at least a couple of posts talking about 'dual frequency' ELT's. Let's see if we can get some technical information shared here so folks have a better understanding of what a modern ELT is...

Firstly, the "old" ELT emergency signal was an audio "warble" encoded on a low-power (typically 100 milliwatts) RF signal continuously broadcast at 121.5MHz.
The "new" ELT emergency signal is a set of digital data including unique aircraft-identifying digits encoded onto a high-power (5 watts) RF signal which is encoded in a short (~50millisecond) burst transmitted approximately every 50 seconds on a carrier frequency of 406MHz.

So with this fancy "new" 406MHz ELT we're dealing with an output power approximately 50 times greater than the "old" 121.5MHz ELT - this really helps get that burst of data through to the monitoring satellites. But what about those 49-or-so seconds in between the 406MHz digital "burst"? Well, for all but one brand of ELT, the time between bursts is filled with the good old continuous wailing of the ELT at low power (50-100milliwatts) on 121.5MHz.

All but one 406MHz ELT are, in fact, "dual frequency" devices.

(If you're interested, the only ELT which transmits solely on 406MHz is the one sold by Emerging Lifesaving Technologies. Technical Standards Order (TSO) C126 has been amended such that ALL newly-produced 406MHz ELTs are dual-frequency units.)
 
It was nice work...
:)
Professionally speaking, a nice repair, as would be expected from a surgeon operating on the face of Christie Brinkley, even at 70 years old. Not that it was a difficult procedure, but I'm sure the pressure was significant.
 
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So with this fancy "new" 406MHz ELT we're dealing with an output power approximately 50 times greater than the "old" 121.5MHz ELT - this really helps get that burst of data through to the monitoring satellites.
Can confirm. On one of the (several…) occasions when my ACK E-04 went off for no discernible reason, it was inside my metal hangar, with all the doors closed. The darn thing still managed to alert my Air Force friends. I was impressed!

I’m starting to think the E-04 is actually a self-aware super-gadget from the future, and that when I finally attempt to destroy it, some random piece of it will still manage to crawl out of the dumpster, Terminator-like, and generate one last false alarm. Just a theory.
 
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