Author Archives: nivagswerdna

About nivagswerdna

Professional Geek

Pragotron Slave Clock – Part 3 – Software

My previous experiments around decoding long wave radio time signals primarily involved using the UK’s time signal MSF60 (https://en.wikipedia.org/wiki/Time_from_NPL) previously known as the Rugby time signal. This transmission no longer originates from Rugby, it moved north to cumbria and seems … Continue reading

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Pragotron Slave Clock – Part 2 – High level design

So with my clock sitting idle on the wall it is time to come up with a design that will send it periodic pulses, once per minute, with +24V and then -24V on alternate minutes… I really want this to … Continue reading

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Pragotron Slave Clock

Whenever I am really busy it seems I get distracted, maybe a failing, I guess, but it always makes life interesting.  Recently I came across a number of articles on electrically driven clocks, slave clocks, which are mechanical devices that … Continue reading

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MSF Clock Synchronisation for Microcontrollers – Part 6 – Decoding the signal

Decoding the signal The specification for the NPL time signal (previously Rugby Time signal) is described at http://www.npl.co.uk/science-technology/time-frequency/products-and-services/time/msf-radio-time-signal with each second of transmission encoding two bits (A&B) except for the minute marker which encodes zero bits but instead marks the epoch. Time information … Continue reading

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MSF Clock Synchronisation for Microcontrollers – Part 5 – A closer look at the noise

Comparing samples from clean and noisy environment I have a highly accurate time source in the form of a Motorola VP Oncore GPS which emits a short pulse every second which is within microseconds of UTC and hence can use … Continue reading

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MSF Clock Synchronisation for Microcontrollers – Part 4 – Noise

Comparing signals from two receivers I have two receivers so thought it would be interesting to put one in a good reception position, approx 2 metres away from any electrical equipment, and another on my lab desk and compare the … Continue reading

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MSF Clock Synchronisation for Microcontrollers – Part 3 – MSF Minute Marker

At the start of every minute Each  minute starts with a minute marker comprising 500mS carrier off and 500mS carrier on with the details of this minute having been encoded in the 58 (negative leap second), 59 (normal), or 60 … Continue reading

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