Do It Yourself

First to guess what this is and what it was used for wins 5 $USDC !

Just found this small device I built 15y ago. If was stored in an meds tube.
Guess what it is and what it was used for and I send 5 $USDC on your Warpcast wallet.

Here is the encrypted answer:

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

To self attest my honesty on this challenge and determine the winner transparently, here is the answer, encrypted for anyone to verify that I did not change it afterwards.

I will provide the key and info to decrypt as soon as we have a winner or in 5 days on Thursday May 22 at 1200 UTC.
No answer will be able to win after the release of the decryption infos. If we have no winner, well, that's sad, but will try another challenge later.

Here's what ChatGPT o3 and 4.5 came up with.

Since it was with medical stuff, I'd guess it was controlling some sort of alarm or siren, maybe based on biomedical data coming from the computer it was plugged into.

Nope. The meds tube is only a storage to keep it safe and dry. It just has the exact right size. It's not medical related.

Here's what ChatGPT o3 and 4.5 came up with.

Since it was with medical stuff, I'd guess it was controlling some sort of alarm or siren, maybe based on biomedical data coming from the computer it was plugged into.
https://chatgpt.com/share/6828fe98-f6cc-8003-8ddd-468c2833e9d1