Noticed this person didn’t want people to access the code for fear of misuse. Thankfully, someone else has already made this for flipper zero before them and released the code!

https://github.com/leedave/flipper-zero-meal-pager

> around 858 microseconds (0.000858 seconds per symbol), which is a weird number, but maybe I’m slightly off or there’s some larger math I’m missing that makes this number satisfyingly round

1/858e-6 sec = 1165 Hz. They were likely trying for 1200 Hz, but the crystal was a bit off.

I want to know how when you see a stack of pager, each one knows its position in the stack so that when the stack decides to go into "attract" mode, it animates them one by one, like an elevator going up.

Somehow when they stack, they know where they are relative to the other pagers (at least something does).

I honestly appreciate the decision to not release the code ("I’m not going to be publishing this code since I can’t think of a good use anyone would have for this besides folks using a low cost SDR and annoying local resturants"). All too often have I seen security researchers release fully weaponized attack tools that then promptly get used by attackers (and not the pranking kind of attackers either).

Could the attacker write it themselves? Probably. Will reducing the cost by providing ready-made code increase attacks? Almost certainly. I wish that more people would consider whether releasing the code will be a net benefit (by enabling legitimate research, education, proof-of-concept demonstrations of vulnerability) or harm (by enabling malicious attacks). Even if the underlying exploit/vuln/feature is the same, form matters: A ready-to-use attack toolkit with multi-client management capability is much more likely to be useful to attackers than defenders, where a simple proof of concept that is hardcoded to show a pre-defined message with no easy way to change that is much less likely to be reused maliciously.

And pranking a pager system sounds pretty harmless, until you realize that a restaurant is likely quite strongly relying on it and essentially DoS'ing it has the potential to affect their business.

Looking at the system for sale [1] now, the lack of security seems to be one of their selling points:

>Multiple keyboards call the same pager. The pager system long range supports multiple keyboard call the same restaurant pagers.

As an aside, all the church nursery references stand out to me. Are pager systems common for that and am I just out of touch?

[1] https://www.amazon.com/Retekess-Restaurant-Adjustable-Remind...

Hi, I’m the author of this: https://github.com/meoker/pagger

very fun article. What is a PHY?