Datasheets end at 85°C, so I estimate that thermal derating of the MF would perhaps give about 750mA @ 145°C which also does not shut down further heating, but will for sure damage permamently all internal soldering junctions. Therefore, a regular thermal fuse (max. 105°C type) will ease your mind better, than this shunt. Frank

They are used to report an estimate of the PPS and 10MHz signals offset from UTC. Typically the values reported are not constant and in the single digit range. (I'm reading from section A.10.31 of the Thunderbolt manual.) This is what I meant when I said "sawtooth". Maybe the wrong term. But I think theses numbers can be used in a controller.

They estimated 7.9. In hindsight, they probably could have gotten better data sooner by using GPS. This news story says that they can see the disturbance in the ionosphere. http://www.cbc.ca/news/technology/story/2012/04/23/f-tsunami-research.html -- These are my opinions. I hate spam.

(In the cold war era I recall seeing estimates of how long the GPS system could operate without ground based attention.)            

Now use robust estimation techniques to get rid of these exceptions and instead follow the smooth line of best-case responses. NTP implementations do something like this already, but at longer timescales, and targeted at Internet links rather than a single local USB link. If the best-case response time is calibrated out, how good can this get?

. > not time based...from what I understand it's based on a received power estimate, matched against antenna patterns. Not particularly accurate. The power measurement is probably good to 0.2 dB (at best).

We know, or at least assume, that the GPS's internal clock is step-less and slowly changing, so if you put a predictive filter on this stuff, it can actually do a reasonable job at estimating which way the rounding of the sawtooth correction went (since it is integral ns).

Estimating the phase and slew-rate, and then use those to calculate the actual through-zero phase would not be too hard. As a consequence you get a slew-rate monitor, which act as an observation of signal level. Cheers, Magnus

. > > Skin depth is probably a good place to start with in roughly estimating the thickness needed. In copper at 50 Hz, a quick calculation suggests 9.5 mm, but this just the depth at which the E-M field decreases by 1/e or 8.7 dB. Thus to get 20 dB attenuation this implies a thickness of about 22 mm, etc.

On Thu, Oct 4, 2018 at 11:00 AM Magnus Danielson wrote: > Regardless, the 53230A does a filtered frequency estimation, which is > great for achieving high precision frequency measures quickly, but not > good for ADEV measures, as it introduces a bias due to the lower > bandwidth of the filtering as compared to the sampling interval