Fun hack for the Ice Tube clock! Who doesn’t want satellite-precise timing? This firmware mod allows you to add any 4800 TTL NMEA GPS module. Check that the module can run from 5V power, and has a wire that outputs NMEA 4800 baud at TTL levels. Do NOT use any RS-232 level outputs, they can easily damage your clock!

Devlin writes –

Our favorite Soviet-Era display that found its way into a present-day kit now displays time from orbiting satellites. A GPS module patched into an Ice Tube Clock with modified firmware will be able to provide a satellite-synced time. The firmware, modified by yours truly, parses the GPS module’s NMEA RMC sentences for the time and date information and then updates the clock’s time and date. Fun was had making sure the alarm went off at the correct times when the time was updated by the GPS. Overall, it was a fun project and we look forward to seeing additional Ice Tube Clock hacks.

We picked up a few of these now-discontinued GPS modules specifically for those that want to use them for time-keeping purposes. They use an older chipset and our testing determined that while they function perfectly fine as a GPS, they are not as accurate as the EM-406 modules we carry for location applications. For that reason, we don’t suggest them for location logging.

However! They will still get you precision time, can get a fix while near a window, and have a built in RTC. Great for hacking your Ice Tube Clock (as seen in our tutorial) or other DIY clocks.

• SONY CXD2951GA-4 chipset
• 12 parallel satellite-tracking channels for fast acquisition and reacquisition
• Built-in rechargeable battery for memory and RTC backup
• Supports NMEA0183 V2.2 data protocol
• Includes cable for power, TTL and RS-232 connections
• Power requirements: 3.3V – 5V DC @ 80mA
• Communications: TTL or RS-232 asynchronous serial @ 4800 bps
• Dimensions: 1.25 x 1.25 x .35 in (32 x 32 x 9 mm)
• Operating temp range: 32 to +158 F (0 to +70 C)