The result assumes I understood the maths and wrote the code correctly! I'm not entirely surprised it's that good because the design is so simple. Provided it's hanging straight, and the spring is about the right boing, there's not much to go wrong. I took your advice last time the suspension was apart by exposing more spring. In the next version I plan to make a new spring longer and thinner as you suggested ages ago.

Moved the clock and installed the new software with GPS. A few bugs!

Tick Amptd Triggr IM Period ClockUNIX ClockHMS NTP UNIX

13288602 0.6531 0.3600 25 830881 125 660137 00:02:05 1671890540 265189

13295731 0.6535 0.3600 25 830595 126 490732 00:02:06 1671890541 096321

13293091 0.6530 0.3600 25 830595 127 321327 00:02:07 1671890541 927374

13290674 0.6532 0.3600 25 830875 128 152202 00:02:08 1671890542 758405

13294434 0.6533 0.3600 25 830723 128 982925 00:02:08 1671890543 589839

13291105 0.6531 0.3600 25 830958 129 813883 00:02:09 1671890544 419660

The amplitude (blue) is much too high, way above the trigger threshold, and despite that the bob is being impulsed on every beat.

The orange pair should be a UNIX timestamp, seconds and microseconds, set to current NTP time when the clock is started. Didn't happen, it started at zero. It is incrementing correctly and the HH:MMS decode looks right too. 127.321327 was 00:02:07 GMT on Thursday 1st January 1970.

Temperature, Pressure and Humidity are missing, probably because I turned the sensor off whilst testing the new version.

Good news though is that the GPS corrected period measurement appears to be working. This was the main reason for upgrading the clock.

So far GPS is holding up. The antenna now looks out of a west facing window, and the GPS module locked immediately rather than taking an age to find enough satellites, always a good sign. But, the availability of good signals might change as the earth rotates and the satellites in view change. A disadvantage of using GPS is poor signals cause my period correction to go potty. When the parts arrive an OCXO will be substituted; less accurate than GPS, but doesn't depend on an indoor antenna.

Dave