Collaborate Disseminate
As far as timekeeping goes, there’s nothing more accurate and precise than an atomic clock. Unfortunately, we can’t all have blocks of cesium in our basements, so various agencies around …read more Continue reading Simulating a Time-Keeping Radio Signal
Could there be a worse fate for a guy with a Swiss accent than to be subjected to a clock that’s seconds or even – horrors! – minutes off the correct time? Indeed not, which is why [The Guy With the Swiss Accent] went to great lengths to keep his …read more
You can win any argument about the time when you have a radio controlled watch. Or, at least, you can if there’s any signal. [Henner Zeller] lives in a place where there is no reception of the DCF77 signal that his European wristwatch expects to receive. Consequently, he decided to make his own tiny transmitter, which emulates the DCF77 signal and allows the watch to synchronise.
A Raspberry Pi Zero W is the heart of the transmitter, and [Henner] manages to coax it into generating 77500.003Hz on a GPIO pin – close enough to the 77.5kHz carrier that DCF77 uses. …read more
Continue reading No Signal For Your Radio-Controlled Watch? Just Make Your Own Transmitter
Buried on page 25 of the 2019 budget proposal for the National Institute of Standards and Technology (NIST), under the heading “Fundamental Measurement, Quantum Science, and Measurement Dissemination”, there’s a short entry that has caused plenty of debate and even a fair deal of anger among those in the amateur radio scene:
NIST will discontinue the dissemination of the U.S. time and frequency via the NIST radio stations in Hawaii and Ft. Collins, CO. These radio stations transmit signals that are used to synchronize consumer electronic products like wall clocks, clock radios, and wristwatches, and may be used in other
Earlier in March we heard about a quirk of the interconnected continental European electricity grid which caused clocks to lose about six minutes so far this year. This was due to a slight dip in the mains frequency. That dip didn’t put anything out of commission, but clocks that are designed to accumulate the total zero-crossings of the power grid frequency of 50 Hz don’t keep accurate time when that frequency is, say 49.985 Hz for an extended period of time.
An interesting set of conversations popped up from that topic. There were several claims that modern alarm clocks, and …read more
Continue reading Ask Hackaday: Is Your Clock Tied to Mains Frequency?
If you are an American, you’ll probably now find yourself in one of three camps. People who are going to see the upcoming solar eclipse that will traverse your continent, people who aren’t going to see the eclipse, and people who wish everyone would just stop going on incessantly about the damn eclipse.
Whichever of those groups you are in though, there is an interesting project that you can be a part of, an effort from the University of Massachusetts Boston to crowdsource scientific observation of the effect a solar eclipse will have on the upper atmosphere, and in particular …read more
Continue reading Crowdsourcing The Study Of An Eclipse’s Effect On Radio Propagation
The US National Institute of Standards and Technology (NIST) broadcasts atomic clock time signals from Fort Collins, Colorado on various frequencies. The WWVB signal on 60 kHz blasts out 70,000 watts that theoretically should reach the entire continental US. Unfortunately for [Anish Athalye], the signals do not reach his Massachusetts dorm, so he built this GPS to WWVB converter to keep his Casio G-Shock self-setting watch on track.
Not a repeater but a micro-WWVB transmitter, [Anish]’s build consists of a GPS receiver module and an ultra low-power 60kHz transmitter based on an ATtiny44a microcontroller’s hardware PWM driving a ferrite rod …read more
Continue reading Micro Radio Time Station Keeps Watch in Sync