Dave explains the what how and why of measuring crystal clock oscillator drift over time.
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http://www.eevblog.com/images/ClockDriftBoards.jpg
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13 years ago lol
I now realize that the crystal is not to be trusted. I use an esp32, using a built-in timer and the crystal, which should wake up twice in 24 hours and wait for a reset button. The crystal was drifting so much it was impossible. Changed the program, so now the esp32 wakes up every hour and checks against the internet if the time is less than an hour left, otherwise it goes back to sleep again. In one hour, the drift is so small that this works. My project is very small relation to yours but well explained and it helped. Thanks.
12 years and still fascinating 👏 👌
I bet with enough time the drift would generally oscillate back and forth like a full sinusoid.
I know I'm late to the party. However you could use a FM ramp up signal from your boat that the hydrophones can pick up and record as well to use in post DSP
this vid has that vintage 2010 smell! 😛
crazy how dated these old vids are looking now Dave!
He is 15 minutes in the 24 minute long video when reaching the actual subject for the first time!
I know it's Dave's thing to go about this stuff totally unscripted, that he's done it for ages and thus my lowly rant here won't achieve anything, but since it's my thing to bitch about it I'll do it anyway.
While I do find the info about seismic activity monitoring rather interesting, it is heavily irrelevant to the actual subject. Even if it presents a (single) use case for it, it becomes a distraction rather than serving the purpose of educating people about electronics.
Anyone else finding this frustrating? I totally appreciate a lot of Dave's audience simply enjoy his random blabber, but since it's become such a big channel and shows a lot in the search results, there must be other's like me who keep ending up here while actually trying to learn about electronics.
Again as I said it's Dave's thing and I'm 100% backing his right to do anything he wishes on his own channel which, simply looking at the numbers, is clearly working but at least I got it out of my system for a bit.
Also, I AM thankful for the vast information internet is bringing to my reach free of charge but the vastness tends to make it equally hard to reach as if it was scarce. Youtube's main goals is to distract you and it happens easily and even if you maintain your focus, it takes unreasonable amount of time to wallow through stuff like seismic activity monitoring to gain knowledge that could just as easily be delivered in less than 5 minutes.
Thanks for the video
I cant follow his eyes and mouth..
Funny to see the dramatic change of the looks of the equipment in the background compared to the current video's in 2020 !!!
Feels like a job for I Q encoding somehow… possible to just derive amplitude and relative phase via multiplicative means? Nice job tho
funny way to explain things but specifically for the topic of Oscillators unfortunately wrong explanations on the terminology for a TCXO and DTCXO was used… A TCXO is not a temperature Controlled Oscillator but just a temperature Compensated Oscillator… similar like DTCXO. It is again just a temperature compensated product but using a more complex compensation using a microprocessor.
Measuring clock stability is such an important part of the GNSS (GPS/Gallileo) system. The method involves using one master clock, which is known to be more stable than the unit under test, and to measure what is known as the Allan Deviation. The Allan Deviation provides all kinds of useful information about the performance of your clock, including what types of instabilities you're dealing with.
Hey hi master
fantastic video. what a classic trick. good to see it done in discrete logic chips like that to get extreme speeds. gotta feel bad for the ocean life tho
You better talk with PTP GM vendors about drift clock.
Can a crystal ocilator switch a mosfet on and off? 😛
Isn't the time-reference of each of these units updated perodically via GPS?
Love your video's, due you have a a basic electronics series. Thank you
Applying logic to solve an unexplored problem. I love this kind of stuff 🙂
Sir, is there a relation with crystal oscillator drift in computers ?
you could have used two oscillators together with an or, then every time it flips you know it's drifting, you can compensate and get half the precision error, with 3 oscillators you'd get 8 times the precision or more, since you can compare two and adjust the third.
Use nasa's solution, if you have more than one you get exponentially less problems.
That's awesome you measured without buying Synchronization tester, you saved a lot of money.