Detect Power Outage (no SIM!)

1. Automate Community
2. Communication

TLDR: This sounds an alarm upon a remote power outage.

Use your old device in "Reporter" mode and current device in "Monitor" mode, to detect failure of a measurable system such as AC power, WiFi network etc.

No SIM card needed for the old device, as this is detected by the *lack* of signal (heartbeat).
WiFi is good enough.

Read more about the protocol here:
https://en.wikipedia.org/wiki/Heartbeat_(computing%29

Requirements:
* The two devices are connected as friends via a Pushbullet chat.

Steps:
1. Adjust Plug-in blocks to set the right Pushbullet chat.
2. Use old device in "Reporter" mode.
3. Use current device in "Monitor" mode.

IMPORTANT:
The first time the alarm is triggered, Android may pop a dialog asking which Timer to use.
This is bad because it blocks the alarm until you select your preferred app.
To have it set in advance, you can fool the Monitor side into thinking a failure occurred by temporarily modifying the polling interval to 1.

Changelog:
2019-06-29 (v4): Removed redundant "take variable" block.
2019-06-29 (v3): Added a "Monitor Silently" mode. Useful for muting it temporarily when you're already at the remote location.
2019-06-28 (v2): Hopefully fixed an uncommon race condition that led to a false positive.
2019-06-26 (v1): First version.