For these residing within the continental US who, for no matter cause, don’t have entry to an NTP server or a GPS system, the following finest method to verify the proper time is thought is with the WWVB radio sign. Transmitting out of Colorado, the 60-bit 1 Hz sign reaches all 48 states within the low-frequency band and is an effective way to get a clock inside just a few hundred nanoseconds of the official time. However in excessive noise conditions, significantly on the coasts or in populated areas these radio-based clocks would possibly miss a few of the updates. To maintain that from occurring [Mike] constructed a repeater for this radio sign.
The repeater works by offloading many of the radio elements to an Arduino. The microcontroller listens to the WWVB sign and re-transmits it at a decrease energy to the rapid space, on this case no additional than just a few inches away or sufficient to synchronize just a few wristwatches. But it surely has a a lot better antenna for listening to WWVB so this eliminates the (admittedly unusual) downside of [Mike]’s watches not synchronizing at the least as soon as per day. WWVB broadcasts a PWM sign which is straightforward for an Arduino to duplicate, however this one wanted assist from a DRV8833 amplifier to generate a meaningfully sturdy radio sign.
Though there have been different comparable tasks oriented across the WWVB sign, [Mike]’s aim for this was to enhance the vary of those tasks so it may sync greater than a single timekeeping system at a time in addition to utilizing components that are extra available and which have a better ease of use. We’d say he’s performed a fairly good job right here, and his construct directions cowl virtually all the pieces even essentially the most newbie breadboarders would wish to know to duplicate it on their very own.
