Devices that still work when the internet doesn't.

Watches & Wearables / alarm clock

Westclox Keno 15550

D0 No Radio — No radio at all. It cannot phone home.

The unplug test

There is no router to unplug and nothing to notice its absence. The clock keeps time and rings its bell alarm purely from a wound mainspring; you rewind it by hand every day or two. It has worked exactly the same way, with no changes possible, since the day it was made.

Why this tier: A traditional key-wound mechanical alarm clock: the movement and the bell alarm are both driven entirely by a wound spring. The manufacturer's own instruction manual states plainly, 'Your clock does not require batteries or electricity to operate,' and documents only mechanical controls -- a time winding key, an alarm winding key, an alarm on/off slide switch, and a mechanical +/- regulator lever -- with no battery compartment, cord, or electronic component anywhere. A device with no electrical power source at all cannot contain an intentional radiator, so this is the clearest possible D0: no radio because there is no electronics to hold one.

Specifications

Account requirednone
Works offlinefully
Forced firmware updatesno
Radiosnone
FCC IDno intentional-radiator grant found
Local controlnone
Phones homenone
Parts availablelimited
Availabilitylimited
Price band$15-30 (seen 2026-09-03)
Vendor risk 0 / 3

Where to buy

Open questions

Sources

Class A is primary (manual, FCC filing, teardown). Class B is corroborated community reporting. Class C is never sufficient alone.

History

Last verified 2026-09-03 — 3 days ago.