#336
Переглядів 53,223
День томуTime is probably the only global standard. Today we will look into how we can create extremely precise timing. And we see how we can get a precision time and frequency reference for our lab
I am a proud Patreon of GreatScott!, Electroboom, Electronoobs, EEVblog, and others.
Links:
UBlox modules with timing pins: s.click.aliexpress.com/e/_dUft1zx
BG7TBL GPSDO: s.click.aliexpress.com/e/_d9bNngZ or amzn.to/2Me5yFD
GPSDO&Distribution box: s.click.aliexpress.com/e/_dUHk5bP
10MHz TCXO (not tested): s.click.aliexpress.com/e/_dSWyiF3
OCXO (ordered, not tested): s.click.aliexpress.com/e/_d8vPLmH
BG7TL Frequency Counter: s.click.aliexpress.com/e/_dT8fnK9
Leo Bodnar: www.leobodnar.com/shop/index.p...
The links above usually are affiliate links which support the channel (no additional cost for you).
Supporting Material and Blog Page: www.sensorsiot.org
Github: www.github.com/sensorsiot
My Patreon Page: / andreasspiess
Discord: / discord
If you want to support the channel, please use the links below to start your shopping. No additional charges for you, but I get a commission (of your purchases the next 24 hours) to buy new stuff for the channel
My Amazon.com shop: www.amazon.com/shop/andreassp...
For Banggood bit.ly/2jAQEf4
For AliExpress: bit.ly/2B0yTLL
For Amazon.de: amzn.to/2r0ZCYI
For Amazon UK: amzn.to/2mxBaJf
For ebay.com: ebay.to/2DuYXBp
profile.php?...
/ spiessa
www.instructables.com/member/...
Please do not try to Email me or invite me on LinkedIn. These communication channels are reserved for my primary job
As an Amazon Associate, I earn from qualifying purchases
@chrisgreece52 3 роки тому
-Time is probably the only global standard Americans : - Yes , yes kiloyards per gallon squared.
@brittsmith7516 3 роки тому
American here. We would never use a commie (that's a joke) prefix like kilo. We would just say "thousand".
@UpcycleElectronics 3 роки тому
Hey! You're not free of our colonial caveman units yet. Sure, y'all dislike our foot length fetish, but the clock still has our hands :-)
@davidparrish1133 3 роки тому
If anyone remebers Digital Equipment computers, some of thier operating systems had parameters in micro-fortnights.
@McTroyd 3 роки тому
You forgot to divide by 8.
@mahudson3547 3 роки тому
@David Parrish - I did my degree project on a PDP8. Never got the timing right...
@tonysfun 3 роки тому
WOW, leave it to Andreas, he will tell you EVERYTHING from the least expensive version to affordable price - doable price! I ran the video 2x, since I missed stuff the first time. I might listen again Wednesday! Thanks Andreas, you are the BEST!
@AndreasSpiess 3 роки тому
This is definitively not a simple topic. I plan to go a little deeper in a future video...
@tonysfun 3 роки тому
@@AndreasSpiess Can't wait! But don't rush it, I have to get some of my brain back - if I can! ha ha ha
@tweebs1 3 роки тому
This channel and project just keep getting better... love that Swiss clock humor!
@AndreasSpiess 3 роки тому
Thank you very much!
@hiker1658 3 роки тому
I appreciate the fantastic job you're doing to investigate and bring attention to these fascinating parts and projects. Way to go!
@AndreasSpiess 3 роки тому
Thank you for your nice words!
@dufflepod 3 роки тому
Excellent video! I'm really enjoying this satellite series. Looking forward to the next one.
@AndreasSpiess 3 роки тому
Glad you enjoy it!
@richleyden6839 3 роки тому
Excellent discussion of a topic, GPS timing, that I had been curious about but knew very little. Thank you for you diligent work.
@AndreasSpiess 3 роки тому
Glad it was helpful!
@PhG1961 3 роки тому
Great video. A great refresh of things of the past and also an update on new things. Well done.
@AndreasSpiess 3 роки тому
Glad you enjoyed it!
@diggleboy 3 роки тому
Really great episode on precision timing. I'll definitely use your investigation and findings to setup my own precision timing at home for my lab.
@AndreasSpiess 3 роки тому
Enjoy!
@BerndFelsche 3 роки тому
Very useful overview. I'll keep it bookmarked for when colleagues ask me about the subject.
@AndreasSpiess 3 роки тому
Glad it was helpful! And it is an honor to become bookmarked...
@avejst 3 роки тому
Great walkthrough as always 👍 Thanks for sharing 👍😀
@AndreasSpiess 3 роки тому
My pleasure!
@shadow7037932 3 роки тому
I was aware of TCXO/OCXOs, was not aware of the GPSDO/GPS TCXOs. Learned something new today. Great project. Keep up the good work.
@AndreasSpiess 3 роки тому
Thanks, will do!
@petejandrell4512 3 роки тому
'10Hz without callibration over a few thousand years, good enough for the girls I go out with' AVE would be very proud ;)
@AndreasSpiess 3 роки тому
So we all know the source channel ;-)
@GnuReligion 3 роки тому
@@AndreasSpiess (gasp) Am stunned that this gentleman with a Swiss accent would stoop so low as to watch that foul-mouthed, talking-hands, Canadee-anne destroy perfektly good, Chinesium tools. Howdaya understandem? AvE: "... you know they say, I am not a gynecologist, but I'll take a look."
@RotorPics 3 роки тому
Nice to see an Uncle Bumblefuck reference, Andreas !!
@AndreasSpiess 3 роки тому
I once worked for Hilti. Is this sufficient ;-)
@simoncollins6650 3 роки тому
Great topic. excellent, made me get better freq reference . Many thanks Simon
@AndreasSpiess 3 роки тому
Very welcome
@kcmichaelm 3 роки тому
I love this topic. I am obsessed with time and have a Pi running a NTP service in my house based on a GPS antenna. Like you did here, I have also used the signal for my own purposes as well.
@AndreasSpiess 3 роки тому
Do you have a link to the project of your NTP server? Maybe I will build also one...
@kcmichaelm 3 роки тому
Andreas Spiess I will link the guide here. I followed the old version of the post and it looks like they refreshed it in 2018, which is good to see updates. It uses the exact hardware I have installed. I have been running this for three years now and it is great. The main idea is that you still connect to an external time server (Stratum-0) to get the base time, but it uses the local PPS signal from GPS in order to maintain that to perfect accuracy. It has been wonderful to have this in my house and be able to point all devices at a local NTP server. ava.upuaut.net/?p=951
@AndreasSpiess 3 роки тому
Thank you for the link!
@DonalCunningham 10 місяців тому
Wonderful explanation of T&T basics! Thanks very much.
@AndreasSpiess 10 місяців тому
You're very welcome!
@jafinch78 3 роки тому
Excellent overview and presentation! Thank you sir!
@jafinch78 3 роки тому
Neat seeing the Adalm Pluto mod you made also. Didn't know about the aliexpress version. Amazing! Amazing what the latest and greatest NEO-#'s are capable of also. Especially if using for tracking with the RTK though that is a completely different topic/subject. I still think there is a way to hack out the modules even with the Digital Block to make a really low noise communication device receiver. Would be awesome to be able to hack into just the RF Block since seems like would be an awesome receiver/detector for a receiver or spectrum analyzer or I guess VNA too.
@AndreasSpiess 3 роки тому
I do not know what is inside a GPS receiver. But I assume it is pretty specialized.
@jafinch78 3 роки тому
@@AndreasSpiess Yeah, was thinking at the least can seal up the GPS module in a shielded case and use the antenna input like for the output of a mixer with a fixed frequency design for either sweeping like for analysis or for just whatever transmitter tuned as a for use as a radio receiver. Though since stuck with the digital block format... would have to design the transmission protocol, if using as a sensitive receiver, to encrypt to the Digital Block format so can be decrypted/translated from the Digital Block format using the transmission protocol format. One of those different ideas I had one day when drooling over the noise floor specs of the latest uBlox modules. Albeit the baud rate will be low... though is improving with each new version.
@Palominostudio 3 роки тому
Awesome video Andreas. Firstly, it is highly informative and useful. Secondly, I could relate to it as it reminded me of a project I did years ago where I had to synchronize a sheet coater with a oven. Although the motors were digitally geared together with incremental encoders, it relied on phase synchronization to keep things in time. The lacquered sheets had to be fed into the holders of the oven at the right position as they came past on a chain. These sheets are what tin cans in various forms and also beer bottle crown tops are made from. Pulses from both machines were used to create sawtooth wave forms and then an error signal was generated by comparing amplitude. A proportional correction was then calculated and added to the digital gearing ratio. The oven being the master generated a signal with a 50% mark space ratio. It was sufficient to only apply correction whilst the signal was high, and then freeze it whilst it was low. So as you say, using a time standard to discipline an oscillator is highly effective, reliable and simple to implement. I love these types of discussions, right up my alley. Thanks for sharing. And I am glad to see your hand seems to be getting better. Best Regards, Duncan South Africa
@AndreasSpiess 3 роки тому
I also love feedback loops. They are one of the most important inventions of humanity!
@lmaoroflcopter 3 роки тому
Brilliant video! Loving this content!
@AndreasSpiess 3 роки тому
Thanks so much!
@JUANKERR2000 3 роки тому
7:03 - My ambition was to be filthy, stinking rich; I failed, but two out of three is not too bad.
@AndreasSpiess 3 роки тому
You are right! 66% is already a good result ;-)
@joshuarosen6242 3 роки тому
@MichaelKingsfordGray I bet you’re fun at parties. It was a joke.
@fatfreddy8089 3 роки тому
@@joshuarosen6242 With a name like MichaelKingsfordGray .I think he was joking.
@tonysfun 3 роки тому
Just another GREAT VIDEO Andreas!!! Thank you for sharing. Have a great week and let us know how is your finger healing.
@AndreasSpiess 3 роки тому
Thanks! The doctor was happy on Friday. But it will take some time till I can drive my Harley...
@tonysfun 3 роки тому
@@AndreasSpiess Yes, but you can use it with electronics and stay away from the dangerouse hobbies! ha ha ha Glad to hear that your doctor gave you a great news!!! We are all happy for you! Stay safe!
@benverdel3073 3 роки тому
Gruss dich Andreas. When I was young we used a cheap FM stereo receiver. We extracted the 38/19kHz stereo pilot-tone out of a national radiostation. These where about the most stable frequencies you could get in the 80s. Then put it into a PLL to get the frequency we wanted. This video brings back good memories. Thanks. I follow you every now and then. But you got a new subscriber today.
@AndreasSpiess 3 роки тому
Welcome aboard the channel! And here you see how things changed since the '80s...
@DavidGlaude 3 роки тому
I am so happy to have acquired the same IKEA clock as you, thanks to your video. So far I have not hacked it to diplay another time. The main issue is that it only synchronise once every hour or so. You cannot get it to move the way you want, or you have to cut the power to make it forget, then be the strongest signal to bring it to the time you want.
@AndreasSpiess 3 роки тому
Did you watch my DCF77 Transmitter video?
@DavidGlaude 3 роки тому
@@AndreasSpiess Yes, I have it because of your Videos. Never invested in the coil to control the clock.
@kwazar6725 3 роки тому
So geil. I was wondering how to get a better reference than tcxo. Thank you so much Andreas.
@AndreasSpiess 3 роки тому
You are welcome!
@sharpbends 3 роки тому
Very good, I liked the demo of outputting frequency from the GPS receiver :-)
@AndreasSpiess 3 роки тому
I thought this is the easiest way to show it.
@bpcorner Рік тому
Enjoyed watching, thankyou! For sake of interested folks also reading the comment: Only AU cut crystal can go into making of ovenised oscillators as the mean of S curve (drift vs temp curve) pivots at 70 degrees, while for Regular Crystal (AT cut) the mean pivots at 25 degrees. I hope I have saved a curious mind trying to put a regular crystal into an electronic oven hoping to achieve better accuracy.
@AndreasSpiess Рік тому
Thank you for the additional information. I did not know that fact!
@johnwest7993 Рік тому
@@AndreasSpiess, also, above a particular temperature a crystal will drift in frequency in one direction, while below that particular temperature its frequency will drift in the other direction, (the S curve.) But there is a plateau temperature where a crystal is relatively immune to frequency drift with time. Which depending on the Xtal cut is either at roughly 70C or 25C, but not precisely at those temperatures. I assume the most precise OCXO's each have their exact oven temperature hand tuned to put that crystal on that temperature plateau, but I do not know this for certain, as Xtal-standard companies are fairly quiet about proprietary techniques for their manufacturing precision, stability, and manufacturing cost control. But that was how I set up my home-brew 1 MHz standard that I disciplined with a TRF WWVB receiver at 60 kHz before the GPS constellation was launched into orbit. It was one of the most interesting projects I ever built.
@fjs1111 Рік тому
Thanks, I learned quite a lot on OCXO's I never knew. Also surprised on the amount of phase drift your OCXO had.
@AndreasSpiess Рік тому
This is an uncommon part and not well known…
@petestephenson662 3 роки тому
I used to live in Switzerland for graduate school, and when I was there I and a few other "time nuts" (there's a mailing list by that name for enthusiasts of precision time and frequency) did a tour of the time lab of METAS, the Swiss national standards lab. The guys in the time lab there were a bit puzzled why we wanted to see their time lab (they don't get many visitors) but they showed us around and we chatted for a while. Nice people. They have a nice set of HP 5071A cesium reference standards, a research-grade cesium fountain clock, and a hydrogen maser that they use to define UTC(CH), and help define UTC in conjunction with other national time labs. They said they used to get a lot of financial support from Swiss watch companies until the companies realized that people aren't buying their watches for keeping excellent time but rather as a fashion item, so eventually the financial support stopped. Now they do a lot of calibration of commercial and industrial time standards, but even that is not as popular as it was because anyone can get intrinsically calibrated GPS-based time and frequency standards and let the USNO deal with all the hard work.
@AndreasSpiess 3 роки тому
I visited the time lab at the University of Neuchatel. They did work for the Galileo program. But I do not know how they are financed. At least for me it was very interesting (I was allowed to compare my GPSDO with their maser...
@andymouse 3 роки тому
Fascinating !
@AndreasSpiess 3 роки тому
You are right!
@samvoelkel2046 3 роки тому
Very fascinating; thanks.
@AndreasSpiess 3 роки тому
Glad you enjoyed it
@andreacodutti1313 3 роки тому
So it's true that swiss people love precise timing
@iflnr978 3 роки тому
yes we do!
@darkstar2111 3 роки тому
Very useful! Thanks!
@AndreasSpiess 3 роки тому
You're welcome!
@Nabilphysics 3 роки тому
Hello Guy with swiss accent, very impressive from Guy with Bangladeshi Accent.
@oniruddhoalam2039 3 роки тому
Hi, also from Bangladesh.
@AndreasSpiess 3 роки тому
Thank you! Never been in your country :-(
@GnuReligion 3 роки тому
Does the Bangladeshi accent differ from that Bengali accent?
@oniruddhoalam2039 3 роки тому
@@GnuReligion Those who are not Bengali, their accent probably differs.
@Nabilphysics 3 роки тому
Dear Andress, Thanks for your kind reply. You are welcome to my Country. I always share your video in our "Robo Course" App. You may download from Play Store.
@losergene7002 3 роки тому
Great stuff.
@AndreasSpiess 3 роки тому
Thanks!
@santorcuato 3 роки тому
Another "Master class" Andreas, thanks. The GPS part is so interesting and affordable for everyone doing any kind of timing... I don't know if it's enough for a separate video... [ES] Otra "Clase magistral" Andreas, gracias. La parte del GPS es tan interesante y asequible para todos los que hacemos cualquier tipo de sincronización... No sé si será suficiente para un video dedicado...
@AndreasSpiess 3 роки тому
BTW: How is the quality of the Spanish subtitles from your point of view?
@santorcuato 3 роки тому
@@AndreasSpiess Let me take a look, I never use them...
@santorcuato 3 роки тому
@@AndreasSpiess 9.7 over 10. There is noticeable that there is a speaker from a sudamerican country. We, spanish speakers, use the Spanish language in a slightly different way at both sides of the Atlantic as British or Americans do with the English. But those are not errors! The subtitles are 100% comprensibles and only a few words can be more precises from a technical point of view. For the purpose of divulgation is a really good job. Yours faithfully ;-)
@AndreasSpiess 3 роки тому
Thank you for your feedback. I shared it with Luciana the translator.
@santorcuato 3 роки тому
@@AndreasSpiess You are welcome!
@AndrewDeme 3 роки тому
Great video....thank you
@AndreasSpiess 3 роки тому
Glad you enjoyed it
@WA4OSH 3 роки тому
Andreas, Thanks for this video. For our microwave projects (Pacific Northwest VHF Society) we use the Leo Bodnar GSPDO with a 5-pole low-pass filter to remove the harmonics. We're on 10, 24, 76 and 122GHz DE WA4OSH
@AndreasSpiess 3 роки тому
I also added a 25MHz filter to get a Sinus. BTW: Is 122Ghz still VHF? I thought it is at least UHF ;-)
@WA4OSH 3 роки тому
EHF :D Take a look at this eval kit: siliconradar.com/evalkits/#sirad-simple www.bay-net.org/uploads/1/2/2/7/122774721/k6ml-122ghzradio-baycon2018.pdf ghz-europe.com/vk2xax-more-tests-of-122ghz-transverter/ It needs a 10MHz reference
@AndreasSpiess 3 роки тому
Thank you for your links. This is mindboggling!
@WA4OSH 3 роки тому
@@AndreasSpiess The resolution of the FMCW radar is much higher than the PIR sensors that you tested in April. Also, check out the NXP CompactRadar www.nxp.com/products/rf/radar-transceivers:MITERWAVEICS#/ I'm trying to get an evaluation kit. Home security that does not get triggered by cats, dogs, birds, deer, etc. but properly identifying humans and cars is my goal.
@AndreasSpiess 3 роки тому
Maybe we will also get cheap stuff from the cars like we get from GSM stations...
@martinsauerteig4882 3 роки тому
Another excellent video. Great comparison of strengths and weaknesses. We can now meet on satellite... ;-)) Thanks a lot
@AndreasSpiess 3 роки тому
Unfortunately not yet. I am not ready. What kind of antenna do you use?
@martinsauerteig4882 3 роки тому
@@AndreasSpiess I ordered the POTY last week as I prefer your concept with a 80cm dish. And I'am shure you'll qrv before me as I have a lot of ham projects in parallel, even though I watched video # 306 a dozen times...
@AndreasSpiess 3 роки тому
I also have a second HAM project. I got a new keyer ( www.i2rtf.com/signature.html ) from my wife and I started to recover my rusty CW..
@LucaRuggier 3 роки тому
How was this comment made 17 hours ago when youtube tells me this video went up 3 min ago...
@mahudson3547 3 роки тому
@Luca Ruggier Not much discipline in their timing..
@HersonBagay 3 роки тому
We install synchronization equipment that uses Cesium clocks as backup if the GPS receiver is down or jammed
@AndreasSpiess 3 роки тому
So it must be an important application ;-)
@HersonBagay 3 роки тому
@@AndreasSpiess Stuff that needs to run properly even if the sh!t hits the planetary fan
@saisrikargollamudi7892 3 роки тому
Can you please make a video on how to choose the right microcontroller, I recently got an MSP432 for my college project and finding it hard to work with
@saisrikargollamudi7892 3 роки тому
@Scott Page USMC Thank you for your interest, My problem is mostly with using code composer studio, I don't see many examples on how to program MSP432 whereas STM32 has got lot resources on web so was wondering if I have switch to that. I am very familiar with using arduino boards, but I was told not to use that.
@AndreasSpiess 3 роки тому
I use Arduinos, ESPs, and Raspberries. Mostly because they have a huge community support.
@saisrikargollamudi7892 3 роки тому
@Scott Page USMC Thank you for your interest sir, TI is sponsoring the kits for us thus we are supposed to use them, I have searched some books and reading those.
@id513128 3 роки тому
Using the GPS clock signal is easier than I thought! (I never know that PPM is also adjustable too) How do you wire the GPS signal to the basement? Do you have to put the module outside and wire the pulse signal into the room? Or broadcast the clock signal as you do with your Ikea clock video?
@AndreasSpiess 3 роки тому
GPS antennas are "active". They have an amplifier built in. So you can have quite a long cable from the antenna to the basement. But for sure the antenna must "see" the satellites.
@id513128 3 роки тому
Thank you for the answer. 😃
@ernestb.2377 11 місяців тому
Hi. Great explanation in a short time span! Short question: in the video at about 18':15" we see the square wave of the cheap GPS receiver. Would you know why the square wave has/looks irregular width, with 2 wider and 3 shorter positive period square? If this works that would be a very cheap solution to a very high accuracy clock!
@AndreasSpiess 11 місяців тому
I do not know the reason for the irregularities :-(
@ernestb.2377 10 місяців тому
@Andreas Spiess I think I know now the Why part. Just watched an interesting video. It seems that the (programmable) output frequency of the gps generator is provided by dividing the main clock of 24MHz. If you choose a frequency that has fraction, then you get a weird mix. For example: 10MHz would be factor 2.4. It seems you get a mix of 12 and 8MHz. More info on: ukposts.info/have/v-deo/hWaEoZqohHdepZs.html
@haffolderhaus 3 роки тому
👀Mindblowing Good 👍👍
@AndreasSpiess 3 роки тому
Thank you!
@etiennebatori2093 3 роки тому
Thank you for the video, I think this is very educative. As always I appreciated the tone and jokes ! I work in a atomic frequency standard lab in Switzerland. I could measure the stability of your GPSDO using one of our hydrogen masers. That way you would exactly know how stable the unit is. What do you think ?
@AndreasSpiess 3 роки тому
Great idea! Can you contact me? You find me on Twitter, Facebook, or in search.ch
@Halabaloosa Рік тому
@@AndreasSpiess I know it's been quite some time, but do you have an update on this? Ever got to check the GPSDO precision and stability with @Etienne Batori ?
@AndreasSpiess Рік тому
@@Halabaloosa Yes, was at the University of Neuchatel, and Etienne tested my devices. They were very stable as long as the GPS reception was good. So the antenna position is more important than the device.
@eznAnze 3 роки тому
@Andreas Spiess, I'm also trying to get external reference to my Pluto but I'm not sure how to wire the UF.L socket in place of the TCXO.. I found some schematics online but I do not understand them nor I can trust the source 😂 so I would be glad if you could explain how you did it, or how it works! :) Thank you!
@AndreasSpiess 3 роки тому
Just look at the diagram. There you see the capacitor between the crystal and the chip. The pin of the U.FL has to be connected to this capacitor. And the ground to ground. the connector ends up with about 45 degrees turned. According to Analog Devices, the external reference should be 1.3V p2p max and should be applied before boot
@eznAnze 3 роки тому
@@AndreasSpiess Thanks for your help! I think I'm pointed in the right direction now! I share a PDF with some info here. If you want to check it I would be glad! Feel free to share it as well drive.google.com/file/d/1SDSqL_ZiND_g2IgaK3W1PT4gsxZjgo61/view?usp=sharing
@ats89117 3 роки тому
This is a very good video. Thumbs up. And of course Swiss people are renown for timing accuracy, so this is consistent with getting the information from a guy with a Swiss accent. On the downside, Swiss people are not known for having lots of sex. For information on that aspect, we will be waiting for a video by a gal with an Italian accent! ;-)
@AndreasSpiess 3 роки тому
As an Engineer, I must ask you for the source, of course. Otherwise it is only your statement ;-)
@microcolonel 2 роки тому
Have you seen the SiTime MEMS TCXOs? Seems like they'd be a good combo with GPS/atomic sources, they outperform many OCXO and are small SMD components..
@AndreasSpiess 2 роки тому
No, I did not see them. They seem to be interesting parts. And, as you write, very small and energy efficient compared to OXCOs. And maybe they are good enough for many applications and can replace a GPSDO. However, precision is not as important for a GPSDO. Stability is more important because the absolute frequency comes from the GPS signal.
@jamesmichener7526 3 роки тому
Like you, I am a retired RF engineer. About a year ago I built my own GPSDO. Comment: the 10MHz output of a U-blox receiver has a lot of jitter, it is coming from the 26MHz osc. I had the U-blox put out 1MHz and then divided the 10MHz OCXO by 10 and used a phase and phase frequency detector and used an ESP-32 as the controller and web browser system monitor. 1 MHz provided gave sufficient phase range to account for jitter from the GPS and keep the initial lock time down to a few minutes. In software I built a variable speed loop... very fun project. You can get down to about 5.0 10e-11
@AndreasSpiess 3 роки тому
Unfortunately, I am just an EE engineer with love to RF, but never sufficient know-how .-) And I have to wait a few years for the pension. Your project is very interesting! I saw the horrible jitter, too. And I have a few "ovens" in the mail. So it might be that I also will try to create such a GPSDO. And I still have ambitions to understand and measure the Allen deviation and compare the different devices.
@jamesmichener7526 3 роки тому
@@AndreasSpiess I should also warn, that I have been told that some of the U-Blox Neo modules are rejects that are sold under another name, then a clone U-Blox sticker is applied, and sold in China. While I don't know if this is true, I can say that the jitter can be >10X worse. If the price is too good to be true.... beware... or buy direct from U-Blox distributors.
@AndreasSpiess 3 роки тому
They are Swiss company and we wanted to do a video about clones. Unfortunately they never came back... On the other hand I canot believe that there are so many rejects in a mordern manufacturing process.
@jamesmichener7526 3 роки тому
@@AndreasSpiess I should not have used the word 'rejects'.... U-Blox sells many different grades/variations of their receivers. You can query the part, and it will tell you exactly what version it is. Someone has removed the sticker on the part, and replaced it with another sticker, which represents it as a more expensive, higher specification part. I have 'altered' parts, but electronic signature reports the truth. So, they are not clone silicon, they are parts where they received a 'label' upgrade. :->
@abdelhakimallal3753 3 роки тому
Great series, Thanks Andreas 73 de 7X2UV
@AndreasSpiess 3 роки тому
You seem binge watching the series. Cool! 73 de HB9BLA
@abdelhakimallal3753 3 роки тому
@@AndreasSpiess I appreciate the effort you're doing to simplify things, You're great (y) Please continue
@scrapwomblecreatives6944 3 роки тому
very nice thankyou, ah yes phase lock loop PLL I remember the old cbs also lol
@AndreasSpiess 3 роки тому
You are welcome!
@artiem5262 3 роки тому
very good summary of a very technical field! Look for "Time Nuts" -- the news group and web site, to find people that spend a great deal of effort on these things, chasing picoseconds... Old HP OXCOs, like the 18011 dual oven 10 MHz oscillator are still superb performers. eBay sourced rubidiums are also good, but the close-in phase noise of rubidiums is far worse than a crystal. With an inexpensive GPS receiver, you can have very good and very stable time and frequency references for your home lab. (If you know what "Allan deviation" is, you're probably a time nut.)
@AndreasSpiess 3 роки тому
Not yet, unfortunately. I still have to learn a lot!
@Scrogan 3 роки тому
How often does the cheap GPS receiver module update/correct it’s output frequency from satellite data? I’d like to see a comparison to the OCXO GPSDO at varying states of signal availability.
@AndreasSpiess 3 роки тому
I do not know. Maybe I will once compare the different sources I have, but I have to learn a lot before.
@marvintpandroid2213 3 роки тому
It's that time of the week again.
@AndreasSpiess 3 роки тому
Glad you like it!
@marvintpandroid2213 3 роки тому
@@AndreasSpiess Definitely, thank you.
@catalinalb1722 3 роки тому
Hello Sir, that means I can program a U-blox chip (can this be a cheap clone version?) to output 27.12 MHz that can be the clock input for a cheap LNB? Thank you
@AndreasSpiess 3 роки тому
As I said: max 24 MHz
@marcinmakan9710 3 місяці тому
Hello, what is the maximum voltage (or amplitude) of a signal that the BGT7TBL FA-3 (or FA-2) frequency counter can handle? I would appreciate your support a lot!
@AndreasSpiess 3 місяці тому
Its datasheet says: CH1 Input sensitivity：50 OHM: 25mVrms-2Vrms or 1MOHM: 25mVrms-10Vrms
@alex-r2pi 3 роки тому
What antenna would be adviseable to use on these ublox modules?
@AndreasSpiess 3 роки тому
They usually come with an antenna. Because I am in the basement I need an active external antenna and an SMA connector
@Aleziss 3 роки тому
is it critical for measuring instruments or radios to have a square or sine wave ? and if I understand the neo-6 can have it's 1PPS pin reconfigure to become a 10MHz reference clock ??
@AndreasSpiess 3 роки тому
It depends on the instrument. You can create higher frequencies with the GPS modules. But they create jitter.
@Aleziss 3 роки тому
@@AndreasSpiess thanks for the reply, it's for a ham radio transceiver that has a 10MHz ref input that required -10dBm (approx 100Hz of drift can be observed with the stock TCXO on 1.2GHz), I thought your u-blox M series gps suggestion was a great idea on top of being cheap !! But since I cannot be sure of the "quality" of the signal and if jitter can cause issue out of the PPS pin to my transceiver, I also cannot measure how much dBm is getting out of this little board as I do not have the proper equipement to measure RF power...
@AndreasSpiess 3 роки тому
I would not use a plain GPS chip for this purpose. Usually a GPSDO is the better solution.
@Aleziss 3 роки тому
@@AndreasSpiess Thank you for all your replies and tips !
@eddys.3524 3 роки тому
the uBlox modules intrigue me. About them I have the following questions: if you set a frequency, lets say 12.000.000 Hz, will that frequency also be generated after a power-down/power-up cycle? What accuracy can I expect if the module is free running?
@AndreasSpiess 3 роки тому
I mentioned in the video: You have two frequencies to select. One comes up without GPS fix, the other with GPS fix.
@DaveMody 3 роки тому
can you use this to calibrate a bench voltmeter?
@AndreasSpiess 3 роки тому
I do not think so. You get voltage references for that purpose
@transmitterguy4784 3 роки тому
On the GPS unit. Does anyone know what the blinking green LED on the bottom of the board rear between the BLOX module and the board corner labeled D2 means? Mine seems to blink at a 1hz rate, but it may mean something else?
@AndreasSpiess 3 роки тому
It is well possible that it is a 1Hz signal because many GPS receivers are programmed to deliver a 1Hz signal.
@ritvarsrizikovs7117 3 роки тому
If Ublox modules are with programmable GPSDO - why to buy those expensive boxes with OCXOs and Altera? Small cheap Ublox GPS modules will be still more stable and precise. Addition with AD9834 and some frequency multiplier for it (Triple 25MHz made with UBlox) Should be enough to make any GPSDO based frequency... Very nice video about oscilators!!! I am building now my labs Frequency generator with 2x AD9834 (Sometimes need phase shifted signals) and 2x AD9833 (For square wave signals and PWM modulated signals). Now I am thinking about putting in this box UBlox and GPS antenna to get GPSDO based Function generator. Thank You Andreas for great explaining!
@AndreasSpiess 3 роки тому
They are good in the longer term. But from what I saw have a horrible phase noise. But I have to do more investigations
@ritvarsrizikovs7117 3 роки тому
@@AndreasSpiess According to Your video at 18:18 its clearly visible that there is really bad 50/50 ratio and phase is completly out of range. Lets try to set 25MHz and repeat the same test. My plan is to use 25MHz setting and after it I would like to put Band filter to 25MHz (That should shift phase but also stabilise it). Another approach can be like You tell about PLL with Low Pass filter - 25MHz with not phase locked loop, but frequency locked loop where error is compensated with some very low frequency filter (VCO). Anyway - Your video was for me very educational and explains me a lot of unknown before things!
@AndreasSpiess 3 роки тому
It depends what you want to get out of it. For sure it will have much more phase noise than for example a OCXO. There is anothe comment conccerning this topic, too.
@PHamster 3 роки тому
So many types of oscillators now a a days! XO TCXO OCXO VCXO SAW MEMS (SiTime) Etc etc
@AndreasSpiess 3 роки тому
I only wanted to cover the "usual suspects". It is already a heavy stuff.
@publicmail2 3 роки тому
CB dayz, freaking and peaking 4 to 100w exciter to 1 kw, into neighbors stereo speakers when not even turned on.
@AndreasSpiess 3 роки тому
I only came to 150 watts with my FT277. But it was illegal enough for my parents ;-)
@ashtonblackberry 3 роки тому
yay!
@AndreasSpiess 3 роки тому
:-)
@mikeydk 3 роки тому
The great thing about standards, is that there are so many different of them...
@AndreasSpiess 3 роки тому
Not for time, AFAIK. Also the Americans use seconds. And this says a lot, I think.
@AndrewDanne 3 роки тому
You made me laugh. Life does get more difficult :-) Thank you
@AndreasSpiess 3 роки тому
You are welcome!
@AndrewDanne 3 роки тому
@@AndreasSpiess Cheers mate, and keep up the great work.
@exmachina4971 3 роки тому
I see we are currently running on the same clock ;-) Iam am also just looking into the GPSDO stuff for an QO-100 SDR setup. I think I will go with the Leo Bodnar Mini @25MHz for the beginning. Have you seen the Lars GPSDO thread on the EEVBlog Forum? There is a ton of information on a (relatively) simple GPSDO Setup with an NEO-xx Module an OCXO and a small Arduino. Took me quite some time to find it, but looks as the best DIY Setup so far. So it should be possible to get a relatively cheap GPSDO for the QO-100 setup. Besides have you seen the setup where someone reprogrammed the Pluto to run on 25 MHz reference clock speed? So you just need one GPSDO! ;-) (It's just a software modification, no deviders, nothing).
@exmachina4971 3 роки тому
Lars GPSDO www.eevblog.com/forum/projects/lars-diy-gpsdo-with-arduino-and-1ns-resolution-tic/
@AndreasSpiess 3 роки тому
One of my Pluto’s already runs on 25MHz;-) And maybe a OCXO alone would be enough for QO100. They seem to be quite precise.
@exmachina4971 3 роки тому
This is one of the cleanest QO-100 setups I found so far (look at the small & clean POTY setup, great!): forum.amsat-dl.org/index.php?thread/2936-pluto-box-solution-w-full-gpsdo-lock/ The Transmitter needs to be replaced, I will go with an SG Labs 20W @2400MHz PA and an github.com/db4um/PA_13cm_2W preamplifier. It took me quite some time and tons of reading threads the last weeks to find the best components, hope it helps.
@AndreasSpiess 3 роки тому
Thank you for the links. This is also my direction. Maybe waterproof.
@exmachina4971 3 роки тому
@@AndreasSpiess Yes, a waterproof outdoor case with all the components included would be the best way I think. And then with a LAN Cable to the Homenetwork. So no losses on the antenna cables. I am just not sure if the temperature changes outdoor wouldn't have a too high impact on the system!? BTW I also stumbled over a nice Bias Tee PCB which injects the LNB DC voltage PLUS the 25 MHz from the GPSDO into the RX Cable. There is also a 50 Ohm to 75 Ohm impedance adaption included. (If you are interested drop me a line than I can look it up in my notes.)
@sontapaa11jokulainen94 3 роки тому
Interesting fact: Due to relativity, the precise clocks in satellites run a little slower when in orbit than on Earth.
@drmocm 3 роки тому
The clocks run slower on earth than in orbit, because the gravitational potential is larger. The clocks in the GPS satellite advances faster than a clock on the ground by about 38 microseconds per day. they would be 45 microseconds fast, but they move at 14,000 km/hr which leads to a time dilation.
@michaels3003 3 роки тому
SJ, Are you SURE?
@michaels3003 3 роки тому
Marcus Metzler, thank you.
@sontapaa11jokulainen94 3 роки тому
@@drmocm Yeah. My bad.
@MrBMohandes 3 роки тому
Andreas, you should have also included Mems oscillators. You can now get these from SiTime. They are available in TCXO's down to 0.5ppm, and now also have sub ppb accuracy OCXO's. These consume significantly less power and have much better over temperature stability, and have none of the Xtal defects such as activity dips. The are also MUCH smaller...if you want to know more you can connect with me in LinkedIn...otherwise take a look at SiTime.com
@AndreasSpiess 3 роки тому
This is a "mainstream" channel and the art is to leave most things away ;-) Maybe in a few years when we can buy them on AliExpress like the MEMS microphones...
@MrBMohandes 3 роки тому
@@AndreasSpiess Andreas, already available in Ali Express, DiGiKey, Mouser, Arrow, etc.....and programmable to ANY frequency by user if required...They are now the worlds largest Oscillator (not Xtal) manufacturer, ship more that Epson, NDK...etc......obviously this is your channel, and you do a great job and this is why you have so many followers...thanks for everything..
@AndreasSpiess 3 роки тому
Do you have an Aliexpress Link for a good MEMS oscillator? I plan to play around/compare with the different technologies and you seem to know more than me ;-)
@stefanmayer444 Рік тому
11:35 how do you determine the accuracy of the most accurate clock ever built? Just wait 30 million years? ;-) What's the reference there to determine the drift?
@AndreasSpiess Рік тому
I assume there is a reference. If you are interested in the details, you can go to the "timenuts" page (leapsecond.com)
@stefanmayer444 Рік тому
@@AndreasSpiess Cool, thanks for the link! If you're interested, I can post the answer to my question, if they can help me with that.
@AndreasSpiess Рік тому
@@stefanmayer444 I decided not to care for the details. Because everybody involved told me that it is a dangerous rathole ;-)
@stefanmayer444 Рік тому
@@AndreasSpiess Haha, you started that topic in the first place ;-)
@PHamster 3 роки тому
Other than a counter, what’s the next best measurement for frequency
@AndreasSpiess 3 роки тому
I do not know.
@linhthai75 2 роки тому
since f = 1/t then we can say most universal constant yield f, as many are affiliate with time. example: heat 1ml of water up 1 celcius with 4.184 watt (all values are exact). You got 1 Hertz (exact).
@Ash-dk7kn 3 роки тому
Just out of curiosity, how to calibrate the frequency of the OCXO?. What are the tools and methods used?.
@AndreasSpiess 3 роки тому
A better reference like a GPSDO is compared and the OCXO is adjusted.
@Ash-dk7kn 3 роки тому
@@AndreasSpiess Thanks for you reply, put how does the OCXO get adjusted?
@mahudson3547 3 роки тому
@Ash If my memory is right, the crystal has two small capacitors, one either side of it. Normally one of them is variable and can be used to trim the frequency when the temperature is stable.
@jimharman5748 3 роки тому
Many OCXOs have a "VFC" pin that allows their frequency to be calibrated by varying the voltage on the pin. That is how the oscillator in a GPSDO is disciplined.
@GnuReligion 3 роки тому
I am a noob hobbyist, not a radio-head, so this sort of precision is over and above. Last year though, while debugging a digital FM tuner (RDA5807M) project, I discovered the frequencies of my watch crystals (2^7hz) differed wildly from each other. Sometimes they were off as much as +/- 30hz, throwing off my tuning. Still do not know any simple way to calibrate these (sigh). Cannot see the end of that rabbit hole. Andreas: Do you know the secret to delivering a good joke? timing
@AndreasSpiess 3 роки тому
True (the timing of jokes). Concerning watches: You are right. Their timing has to be quite precise. I think a GPS module programmed at the crystal frequency and hooked to an oscilloscope would be en interesting experiment...
@avamander. 3 роки тому
Scullcom Hobby Electronics channel has made a very nice video series how to build such a frequency standard for cheap at home. I really recommend if you don't want to dish our hundreds of dollars but need a "bit" more than an Arduino can provide.
@AndreasSpiess 3 роки тому
I saw his videos. Unfortunately he is no more active for the moment. I am not sure if you get it much cheaper (case and PCB included)
@notofinterest 3 роки тому
Next Video: Building a atomic clock cause im swiss and a shift of 2 seconds in 10 billion years is not acceptable 🇨🇭 😂
@AndreasSpiess 3 роки тому
Exactly! And I learned a lot...
@rakotondramananasamuel3970 11 місяців тому
Is it possible to use this with usrp b200 or B210? any help please.
@AndreasSpiess 11 місяців тому
I do not know if those devices have a 10MHz reference input.
@rakotondramananasamuel3970 11 місяців тому
@@AndreasSpiess yes it's have
@AndreasSpiess 10 місяців тому
@@rakotondramananasamuel3970 So you have to check if the voltage levels match.
@mattko 3 роки тому
❤️
@AndreasSpiess 3 роки тому
:-)
@srinivassanrajavelu8040 3 роки тому
Make video on GPSDO homebrew
@AndreasSpiess 3 роки тому
This is probably not a project for this channel. Too specialized...
@srinivassanrajavelu8040 3 роки тому
@@AndreasSpiess your work is great thx for the reply
@jimharman5748 3 роки тому
@@AndreasSpiess I have built several GPSDOs using surplus 10 MHz OCXOs, low cost GPS modules, and Arduino processors. The project is based on a design originally posted on EEVBlog by Lars Walenius. This has been a very interesting project to update my 40-year old electronics and programming skills. I would be happy to share the details if you are interested.
@HelmutTschemernjak 3 роки тому
Great video, as always. Do you now about a basic 10 MHz distribution box, just 10 MHz in and six or similar 10 MHz out? I don't believe that a OCXO is needed for this, maybe to continue if the 10 MHz ref is down.
@AndreasSpiess 3 роки тому
I read they sell it also without oven, but I do not know where. I assume the oven does not add a lot of cost...
@artiem5262 3 роки тому
Look at the distribution amps from tapr.org -- they still have the TADD-1 distribution amp available, which is a low noise, isolated amp for 10 MHz.
@michaels3003 3 роки тому
Andreas, I know you don't have time, but you would be a great teacher/professor at some institution of "higher learning."
@AndreasSpiess 3 роки тому
I sometimes do lectures. But I only reach a few people. Here I cna reach thousands. More efficient ;-)
@esteban- 3 роки тому
Institutions are a scam. Knowledge should be free as free beer and free as in freedom.
@AndreasSpiess 3 роки тому
@Esteban: As a consumer it is easy to ask for everything free. It looks a little different if I have to feed my family... And the most important question: What do you contribute?
@esteban- 3 роки тому
@@AndreasSpiess Everybody does need to eat and have basic needs. Every bit of knowledge we share for free allows people in a worst situation than us to get in a better situation. Imagine if you as a kid would have access to your videos as an adult. I firmly believe people will contribute when they are able. Those that take advantage and don't contribute are a minority. I'm extremely grateful for your videos being accessible for free and I try to use your links when buying, if in the future I can do more I will. I'm a lucky one from my country (Argentina) and I managed to learn English, electronics and informatics mostly thanks to people like you that share your knowledge on the internet, otherwise I'd probably be flipping burgers.
@JoshuaJayG Рік тому
I went through all your QO-100 videos again with more intent on learning some specifics. I am currently planning to replace the crystal LO in my Ukrainian transverter with a GPSDO. I have come across an interesting project that is much more than just a GPSDO but that can do that to. Have you heard of RF Zero? It's a Danish ham's creation. Very interesting. 73 DE KJ7LVZ
@AndreasSpiess Рік тому
I just had a look at this project. Very interesting!
@davidtzaig5947 3 роки тому
Dear Andreas, the UBLOX use 24Mhz for the internal crystal so if we want 10Mhz we got a lot of jitter. your oscilloscope screen capture does not shows that because it in single capture mode. ** Do you think we can replace the internal UBLOX crystal for 20Mhz so divide by 2 will give us a jitter free 10Mhz? **
@AndreasSpiess 3 роки тому
To get precise timing you have to use a OXCO or a TXCO and discipline it with a GPS. The GPS module always will have jitter.
@davidtzaig5947 3 роки тому
@@AndreasSpiess Dear Andreas i replaced the neo7 onboard TCXO with external osc and did got a visual jitter free 10mhz. you can watch this video and read my comment. from what i read the pps is already disciplined but cannot output 10mhz because the neo7 has a fractional n synthesizer that cant divide to exact 10mhz. however it does 8mhz,12mhz jitter free. the internal tcxo is 26mhz . you can watch this video and read my comment. ukposts.info/have/v-deo/hWaEoZqohHdepZs.html&lc=UgxHxrVXMsb_1tVLoP14AaABAg.9E6zqlDAGUC9E7I3ry0Mr3
@VincentFischer 3 роки тому
2:42 LOL. Sometimes I think you don't take this seriously xD
@AndreasSpiess 3 роки тому
True! If I stop laughing I am probably dead ;-)
@rolandgraf3447 3 роки тому
Great your UKposts show! But I would prefer it very much if your videos would continue to be numbered. It's much easier to reference them and much more practical to say to a colleague: "Have you seen video ### by Andreas (the guy with the Swiss accent) yet?". Or sometimes I just write down: "See Andreas Swiss ##" . :-) Many thanks for your series!
@AndreasSpiess 3 роки тому
They stay numbered, just not the last 10 or so...
@felenov 3 роки тому
You can always buy a Hewlett-Packard caesium clock for your lab
@AndreasSpiess 3 роки тому
I am not sure I could convince my wife ;-)
@santorcuato 3 роки тому
@@AndreasSpiess But, Andreas a clock is a clock... and I hear some about clocks in your country.
@AndreasSpiess 3 роки тому
But a Swiss Franc is also a Swiss Franc ;-)
@felenov 3 роки тому
@@AndreasSpiess just say it's the king of all clocks
@LiyangHU 3 роки тому
4:47 👈 Hand-ception!
@AndreasSpiess 3 роки тому
:-))
@tbandikoota 3 роки тому
Have you considered using the PPS (Pulse per second) output on the $12 GT-U7 Gps receiver boards? Its a tiny board and works really well as a GPS with Arduino or equivalent boards. Here is the Amazon link to the product: TeOhk GT-U7 GPS Receiver Module Navigation Satellite Microcontroller GPS Compatible NEO-6M 51 Microcontroller STM32 with 1x Active Antenna www.amazon.com/dp/B07RPVYSG5/ref=cm_sw_r_cp_tai_Yba.EbN4B5YFQ
@AndreasSpiess 3 роки тому
All GPSDOs use such modules to "discipline" the crystal. But their short-term stability is not great. Maybe I will make a video about that in the future.
@emilalmberg1096 3 роки тому
So many fun jokes in this video!
@AndreasSpiess 3 роки тому
Glad you liked it!
@TangoMikePapa 3 роки тому
You are funny old man!!
@AndreasSpiess 3 роки тому
Thank you!
@electronic7979 3 роки тому
👍👍👍
@AndreasSpiess 3 роки тому
Thank you!
@m1geo 3 роки тому
11:51 - "Clumsy and expensive" :) I would definitely knock that all over onto the floor, probably with the back of my chair or a coat sleeve! And then what would we use to recalibrate it?! :)
@AndreasSpiess 3 роки тому
I am not sure if you have to calibrated these clocks as they use a material constant. (At least that is what I understood.)
@m1geo 3 роки тому
@@AndreasSpiess Very true. But don't underestimate my clumsiness to take out atomic physics, too! 😂 Cheers, M1GEO.
@ericon.7015 3 роки тому
Andreas, I think you'll love this article about magnetic amplifiers that could be a good source for another video. www.nutsvolts.com/magazine/article/the_magnetic_amplifier
@AndreasSpiess 3 роки тому
Thank you for the link. I did not know about it but it seems more focused on motor applications and maybe is also outdated because of the cheap silicon parts today.
@UpcycleElectronics 3 роки тому
How accurate is the ublox 1pps compared to your other GPSDO's? The "timenuts" mailing list (posted online and easily found by searching), has a bunch of information about why the ublox 1pps signal doesn't work as a GPSDO. Basically, the module's internal frequency is not divisible to an integer of 1. The modules are not made for this purpose and this results in a lot of jitter. My grasp of the subject is weak, but from what I've read, the 1pps signal quality is not much better than the module without any satellite signal at all. I would love for someone to really break this down and prove whether this is true or not. I know of a lot of people that have tried to build a ublox based GPSDO, but no one that actually uses the device in practice afterwards. I get the impression they all assume they are the exception and must have made a mistake. I don't think anyone has succeeded though. There are enough examples of people attempting to build this project that more and more people keep trying. Several people that have built one of these ublox GPSDO's, later acquire units like you had here. Thanks for the upload. -Jake
@AndreasSpiess 3 роки тому
The u-blox really has a horrible jitter. But it is precise in the long run. So it depends what you want. For a stable oscillator you need an OCXO to discipline. If you just want to build a frequency meter I assume it would work for most cases.
@lottery248 3 роки тому
a regular quartz clock would easily end up slowdowns after 1~2 years of continuous use. 🤔
@AndreasSpiess 3 роки тому
We always use our clocks continuously here in Switzerland ;-)
@jamesgoacher1606 3 роки тому
That was very interesting. I was with you for quite a time (no pun intended) but soon after the Crystal Oven which was used in my formative years in Valve Oscilators for AM Ham Radio you went away from me. A very full episode, thanks.
@michaels3003 3 роки тому
Just watch it more than once.
@jamesgoacher1606 3 роки тому
@@michaels3003 Are you - sorry Mr Spiess - of the opinion that I do not? Generally I tag the episodes to their directory in my Email Client because this contribiter is of value to me and sometimes, not always, record as well. As for what this mysterious comment you have made refers to, I have no idea. Are you referring to the bit were I mentioned my early years with Amateur Radio or something else it is not clear. Smart (supposedly) comments are pointless. Sorry Mr Spiess, the poster irritated me. Reminds me of the daft reply to post of "rtfm" or in the case of early Linux read the Manual files. All of which would have been more understandable to a Human type Person if written in Hieroglyphics.
@AndreasSpiess 3 роки тому
@James: Glad you enjoyed it!
@oniruddhoalam2039 3 роки тому
7:06 My Asian parents: Did he just utter that word in public!?
@jamesgoacher1606 3 роки тому
:-) I have no idea why he was expecting it I find it very hard to come by these days.
@AndreasSpiess 3 роки тому
@James: I assume you talk about the money ;-)
@jamesgoacher1606 3 роки тому
@@AndreasSpiess :-D
@kwinzman 3 роки тому
The first sentence in the video immediately had me shouting out: that is the most wrong thing I heard all day and in so many different forms of interpretation. In a physical sense time is relative. And in a standards sense there are so many standards: leap seconds, time zones, ...
@AndreasSpiess 3 роки тому
You are of course right!
@dicktonyboy 3 роки тому
Who is going to fly in the coming 'brave new world'?
@AndreasSpiess 3 роки тому
Good question. When we have e-bikes ;-)
@dicktonyboy 3 роки тому
@@AndreasSpiess Well the offer is still there to convert your motorbike - stacks of video potential.
@AndreasSpiess 3 роки тому
You might remember: My e-Bike was at the Black Sea... And Harley Davidson tried to make an electric bike, without success...
@ADILKHAN-er9tp 3 роки тому
"Earn lot's of money and do have lot's of sex" 😉😉😉
@AndreasSpiess 3 роки тому
Did you think differently?
@muemey 2 роки тому
For me it was impossible to get a clean 10MHz signal from an Ublox-8. 12MHz is clean, 24MHz is clean as well, but 10MHz is not. When I look to your oszilloscope screen shot at 18:15 I beleave, you have the same problem. The frequency 10MHz is displayed, but the broadness of the individual peaks changes from peak to peak. So it is 10MHz on average, but it is not a 100ns period. Looks like 24MHz (or a multiple of this) is kind of a sampling rate for the time pulse generation. For lower frequencies, this sampling doesn't matter. But anyway, thanks for your perfect tutorials. 73, DC0UB
@AndreasSpiess 2 роки тому
That is why we cannot use a cheap GPS receiver for radio applications and must build such a GPSDO where the frequency is produced by a proper oscillator and is only "disciplined" by the GPS.
@chuxxsss 3 роки тому
Oh sorry mate, to many year using the stuff. Oven control oscillator and gps governed.
@AndreasSpiess 3 роки тому
Good stuff!
Andreas Spiess
Переглядів 311 тис.
ZAFER YILDIZ
Переглядів 24 тис.
HB9BLA Wireless
Переглядів 37 тис.
Immersed
Переглядів 6 млн
Creative Passion 88
Переглядів 750 тис.
Є-Дрон
Переглядів 40 тис.
Fun With Screen
Переглядів 55 млн