HamClock is a kiosk-style application that provides real time space weather, radio propagation models, operating events and other information particularly useful to the radio amateur. HamClock was introduced in an October 2017 QST article.

In early 2026, the community of HamClock enthusiasts was sad to learn that the creator of HamClock was now an SK and that the HamClock site announced:

HamClock has reached end-of-life, the last release is version 4.22. All HamClocks will cease to function in June 2026. Thank you for your interest. Elwood Downey, WB0OEW, ecdowney@clearskyinstitute.com

Clearsky's HamClock consisted of an open source front-end client and a closed-source backend server. The client required the backend server to work. Since the news, a few efforts have kicked off to maintain or create something similar for the future.

The HamClock project is the kiosk-style client that users run in their home network. The HamClock client requires a server-based backend to function. An installation requires selection of the backend server to which the client will connect.

The team at hamclock.com have created a closed-source backend compatible with Clear Sky Institute's HamClock client.

The Open HamClock Backend (OHB) project creates an open source project compatible with Clear Sky Institute's HamClock client.

To maintain compatibility between variants of the HamClock client and the HamClock backends, this organization includes a standards repository to define communication between the client and the backend server.

Clearsky's history of revisions, release notes and community contributions are archived in a respository, as well.