Lars gpsdo pdf. Note that support for the Lars GPSDO is a bit sketchy.

Lars gpsdo pdf Oct 3, 2018 · You can also use it as an "extra" input device with the GPS receiver as the main input device. Aug 30, 2020 · The GPSDO was run continuously for more than 24 hours before collecting the data shown in the attached. 1. Dec 8, 2019 · Just a sidenote: If you have a RaspberyPi connected to your GPSDO, you can run LadyHeather on it. pdf (182. GPS disciplined oscillator based on Lars GPSDO, ported to PIC Resources. 0 license Activity. All GPS satellites are equipped with synchronized atomic clock. pos suffix Nov 27, 2019 · UPDATED with finished chart I was able to very gradually increase the TC value, and I'm now running at 700 seconds with a damping factor of 3. I would like to move all the serial connections to the back of the GPSDO enclosure, and do the same for the new enclosure, to keep these wires out of the way and short. vscode","contentType Inside the GPSDO The GPSDO uses this inherent long term accuracy of the 1pps signal to gently steer the local reference into perfect timing. There are four PDF documents, the original blog, and an interesting blog from another constructor. PDF files have been merged into one file. The 2nd order loop has an w 0 = 2p 0. 3. My Lars GPSDO has a high grade NEC oven and M8T, with a roof mounted “mushroom” antenna. ) Logged Mike99. After more than 7 months (or so) when it stayed locked, it started loosing lock every few days. One is 10 seconds gate for testing. SBSpectrum at 25 MHz has a resolution of PCB based on Lars GPSDO published in the EEVBlog forum - Qw3rtzuiop/Lars-GPSDO-PCB Example 1: LARS GPSDO • MC4046 creates charging pulse • Diode + resistor as current source • ADC of Pro Mini measures voltage • Resistor over capacitor discharges before next pulse • 1 ns resolution. {"payload":{"allShortcutsEnabled":false,"fileTree":{"":{"items":[{"name":"XGerber","path":"XGerber","contentType":"directory"},{"name":"pictures","path":"pictures Sep 20, 2019 · Hi, I'm having some troubles with my Lars GPSDO. 66 kB - downloaded 162 times. Lars GPSDO Controller pp 8-14 Lars GPSDO Controller pp 15-18 Lars GPSDO Controller pp 19-21 The original Lars Walenius blog (while it still exists) Paul's Blog (has interesting performance results and useful ideas - even a circuit board). PCB based on Lars GPSDO published in the EEVBlog forum - Lars-GPSDO-PCB/README. 3 watching. I caught some events that seem to be satellite related, unless the OCXO shifts phase all of a sudden. . Contribute to VU3RAZ/Lars-GPSDO development by creating an account on GitHub. 3-5V and the 1PPS is accurate on the positive going flank. The way to use TimeLab to characterize your GPSDO is to collect the DAC values and import them into the tool, while converting them back to a 10 MHz frequency representation. 2. The 6. pdf (710. In his PDF Lars explained that he tried a 1N4148. The M6 uses only GPS satellites, the M8T is configured for fixed location with SBAS turned off, GPS and Galileo satellites both used together. 58 Available at step 11 Hi guys, What is a GPSDO ? GPSDO means: GPS disciplined oscillator. Oct 23, 2021 · Author Topic: Lars DIY GPSDO with Arduino and 1ns resolution TIC (Read 336398 times) Nov 1, 2024 · FWIW, attached is a non averaged plot of a Lars Walenius type GPSDO (as discussed elsewhere on this forum), fitted with a high stability ovened oscillator and a timing grade GPS (M8T), compared to a Leo Bodnar GPSDO which uses a low grade navigation type GPS and a TCXO (temperature compensated crystal osc). Forks. For any GPSDO the slope of the curve is supposed to be negative (variance decreases with increasing tau) until the crossover point where the variance of the GPS time signal takes over. I've also attached a very interesting document to read. pdf (62. Oct 16, 2020 · Lars writes that "With a TIC_offset of 1,000, the GPSDO will go between min and max if the max ADC is less than 1,000. Aug 6, 2018 · The GPSDO is intended as reference for a satellite PLL LNB (with an LO of 9750 MHz locked to 25 MHz, i. 49 kB - downloaded 208 times. My objective is to keep Lars' code mostly intact without any changes or adding any new features, but add comments, rearrange the code, correct the indentation and other formatting details, etc to improve readability and maintainability. {"payload":{"allShortcutsEnabled":false,"fileTree":{"fw/lars-code-improved":{"items":[{"name":". GPL-3. pdf at main · AndrewBCN/Lars-DIY-GPSDO These are the original files for Lars' DIY GPSDO EEVblog project by Lars Walenius - Lars-DIY-GPSDO/What is Lars Arduino based GPSDO Controller page 15-18. It works but its a visual embarrassment. md at master · Qw3rtzuiop/Lars-GPSDO-PCB Mar 8, 2016 · My own rule of thumb is also that AT cut OCXO´s (and good VCTCXO as DOT050V) need time constants in the GPSDO of about 10-100secs, SC cut OCXO 100-1000secs and Rubidium 5000-20000secs to match good GPS receivers. GPS module receives t… Apparently Lars was the only member of his family with any interest in electronics, and I believe he wanted other electronics hobbyists to have full access to his project, this is why putting the project under an Open Source license while retaining Lars Walenius copyrights seems the right thing to do. CH2 (magenta trace) is monitoring the output from my very much modified cheap Chinese "toy" FY6600-60M AWG into which I'd fitted a 10MHz OCXO (plus a 5 times clock multiplier chip) to replace the original and rather crap 50MHz smd XO Feeltech had cheaped out These are the original files for Lars' DIY GPSDO EEVblog project by Lars Walenius - Lars-DIY-GPSDO/What is Lars Arduino based GPSDO Controller page 1-7. Mica capacitors are very precise and stable and have extremely low temperature effects on the capacitance. ) Jul 31, 2020 · Lars has several examples in his documents, go read them if this is new to you. pdf (58. Feb 25, 2021 · Built a second GPSDO based on the circuit published in the . 2 TimeLab VI (xE4) - gpsdo LEA6T IDOf. You could use another GPSDO with known performance parameters as a reference. These are the original files for Lars' DIY GPSDO EEVblog project by Lars Walenius - AndrewBCN/Lars-DIY-GPSDO Hi Andrew. Lock is considered 5 time constants (160s) wi May 22, 2023 · Based on my work with a very high precision and resolution reciprocal counter measuring my current GPSDO, it became apparent that I needed a much better GPSDO design to be used as the external reference clock for the counter. PCB based on Lars GPSDO published in the EEVBlog forum - Qw3rtzuiop/Lars-GPSDO-PCB Oct 16, 2022 · Re: Lars DIY GPSDO with Arduino and 1ns resolution TIC « Reply #1147 on: January 25, 2023, 11:56:50 pm » Things are looking much better now, except there seems to be a very slow downward drift in my DAC values. (The glitch at 1. 47 kB - downloaded 5131 times. a derivative of Lar's Arduino GPSDO. I used two 6-channel 74HC14 as buffer for the outputs, I used three parallel inputs for the 1pps, three for the 10MHz, three for the 5MHz and three for the 1MHz I got from the 390 at pin 6 because of the better 60/40 duty This is a significant improvement to the first version - paulvee/Lars-GPSDO-V4. Files for my Lars GPSDO project_Paulvee. Sep 20, 2020 · The FE-5680A type ones come in many different variants, and usually have a coarse temperature compensation that causes frequency jumps. PDF attached to the first post. These are the original files for Lars' DIY GPSDO EEVblog project by Lars Walenius - Lars-DIY-GPSDO/What is Lars Arduino based GPSDO Controller page 19-21. There is no other method (including the SBSpectrum method mentioned on the Reference & Dividers page) that can 'see' stability down to better than 0. If you want to change the second gate in source code. md at main · AndrewBCN/Lars-DIY-GPSDO PCB based on Lars GPSDO published in the EEVBlog forum - Qw3rtzuiop/Lars-GPSDO-PCB Aug 16, 2020 · For a DIY GPSDO Lars-style, it doesn't matter if you use Galileo or GPS. I powered Lars' DIY GPSDO back on and got a "lock" within 10 minutes! Dec 8, 2020 · c4600. 2 There aren’t any releases here You can create a release to package software, along with release notes and links to binary files, for other people to use. ), and I've been using an opamp for driving the OCXO and the second one for buffering the ADC (inside my stm32). Below is the MDEV report that I started with 700s and a damping of 3. The filtx10 values will give you the min and max. The version of the Arduino code I use (gpsdo_V3_70) is a modified one from Lars' original to be able to use the circuit without the 1Mohm discharge resistor. Read these carefully. I have done some cleaning for this project. Aug 23, 2022 · Looking at the circuit diagram of the Lars gpsdo you posted, I noticed the use of two pwm pins to create a 16 bit DAC. 2/QA for BOM 10MHz GPSDO V4. ) Logged Johnny B Good And it has a display My Lars GPSDO uses a stable voltage reference and potential divider to trim 10 MHz Simple GPSDO by James Miller G3RUH 2007 November 1. Oct 16, 2020 · The Nano TxD, RxD and Gnd signals are already available on the front-panel of the GPSDO, but the NEO signals are only available on a header inside the GPSDO enclosure. It also implements a PID based fan controller for the ambient temperature of the PGSDO enclosure itself. Description The Navman TU30-D140-221 Jupiter GPS engine has a high accuracy 10 kHz output synchronised to UTC. A square wave also works. As you have a Jupiter-T I would definitely use that first. The 7. Search for DIY GPSDO. Aug 11, 2017 · What is Lars Arduino based GPSDO Controller page 19-21. (fed through a 3K9 resistor from the 8V to get a 1mA current) The result is so remarkable it is beyond belief! Jan 20, 2021 · Lars DIY GPSDO with Arduino and 1ns resolution TIC - Page 35 Bliley NV47A. I think Lars' version is using that somehow (I do not use Lars' system). It's line 183, 185 and 196, 198. Clearly to me the reason why the time constant in Lars' DIY GPSDO is set in the range 100~1000s is because as in any GPSDO we are trying to combine the stability of the inexpensive OCXO with the stability of the PPS from the inexpensive GPS receiver, and we only want to start "disciplining" the OCXO at around the point where the two ADEV curves from the Aug 16, 2017 · The nice thing with Lars GPSDO is that almost every GPS module with a 1PPS out can be used if the amplitude is 3. The serial input from the GPS is not needed, only the PPS pulse. You can compare your GPSDO to the atomic clock DCF77 radio signal from Mainflingen. You could use the three-cornered hat method, which requires two more clocks. I added comments to a document that they used to ask for my input. 2, You can take your GPSDO to a lab equipped with an atomic clock or a calibrated rubidium clock. May 27, 2021 · Not to brag, but the STM32 GPSDO is to the best of my knowledge and as of May 2021, the most feature complete and sensor-rich DIY GPSDO described on the net since Brook Shera's July 1998 GPSDO design*, and compares well to any commercial GPSDO available for less than $1k. Readme License. Stars. 7 May 14, 2021 · Hello Bob, Yes, it uses a (recycled) square wave 5V 10MHz OCXO. These are the original files for Lars' DIY GPSDO EEVblog project by Lars Walenius as published in the EEVblog thread: https://www. 6 kB - downloaded 145 times. , I completely rebuild the circuit. multiplification factor is 390 and phase noise impacts with the square of this mult factor (so 20log(390) dB). The oscilloscope trace is exactly that, taken from the output of the OCXO. I'm not yet sure if it's going to be an actual improval, it's just my take on the topic and it's deviating from Lars Walenius' design in several aspects. During the past week it hasn’t missed a beat, although I don’t have it connected to USB, only monitoring via a ZL1BPU LCD display on the Arduino. I tried to read the text in Lars' PDF, but (apparently) I 'm missing/overseeing something when it comes to using TimeLab. Presumably the 10 bit ADC is being oversampled to gain an extra 5 to 6 bits to match the effective PWM resolution? Dec 30, 2018 · Lars DIY GPSDO with Lassen GPS compared to Trimble UCCM GPSDO module. The SI5351 is controlled by special SW included to enable the SI5351 to be set with 1/1000 Hz accuracy. Feb 17, 2024 · Re: Lars DIY GPSDO with Arduino and 1ns resolution TIC « Reply #1249 on: November 23, 2024, 09:01:58 am » Johnny I use a common LM7805 with heatsink in my Lars/Murray GPSDO. This is the circuit of the one I built, and it is also available as a PDF: GPSDO circuit. I once ordered a selection from a China source. *: the jitter in the PPS is really what we are interested in, because it's the noise "floor" that the Mar 29, 2019 · That is explained by Lars very nicely in "What is Lars Arduino based GPSDO Controller page 1-7. Source code can be open by avr studio 7. A print board layout for the above circuits is available as a Sprint 6 layout. 0. Maybe $15-20 Apr 12, 2022 · Actually the STM32 GPSDO can achieve a PLL "lock" much faster than Lars' GPSDO and does not need the educated guesswork of a correct value for the "gain" in Lars' algorithm: we can calculate a nearly optimal "gain" value (or perhaps not optimal, but "good enough" gain value) during the calibration procedure. html at main · paulvee/Lars-GPSDO-V4. You have to design the low-pass filter after the XOR (not an easy stuff, btw. PCBway had some questions about the parts they used for a customer that wanted a full assembly. 007 Hz and damping d =0. Two variations: (1) the power supply is a 7. PS: Lars is using the 5MHz for feeding the Timer1 (200ns clock) for some internal purposes - (ie. 4. 000 222 Hz with a n=25112. My version follows the LARS TIC circuity exactly, and the rest of the Releases · paulvee/Lars-GPSDO-V4. As long as the time pulse is in the right ballpark, it'll be fine. Oct 11, 2023 · Patrick, my guess is that it’s the oven. I have also made some cleaning in repository. 1V, since the 1N4148 has a larger forward voltage drop (around 0. The original circuit is more or less, this one (PDF): ZL1BPU GPSDO circuit . Paul's Blog (has interesting performance results and useful ideas - even a circuit board). pdf at main · AndrewBCN/Lars-DIY-GPSDO Nov 4, 2021 · There is very obviously a problem. Note that support for the Lars GPSDO is a bit sketchy. Dec 21, 2018 · Hi all, I just finished putting it all in a box. One for the VCF input, and I just used what I had available. It would be great to see more of the principles of accurate measurement incorporated into the body of knowledge that technically literate people learn to be so. tlm File Edit Trace Display Legend Measurement Masks Scripts Acquire IE-12 IOS Trace OCX0131-100-1 dacstep IE-II + ne07m ext ant tc500s - ref rb3 DOT050 gpsdo lea6t int ant not fixed mode tc100s - ref Rb3 DOT050 gpsdo lea6t int ant fixed mode tc100s - ref Rb3 DOT050 gpsdo lea6t int ant fixed mode tc25s - ref Rb3 Nov 12, 2019 · Re: Lars DIY GPSDO with Arduino and 1ns resolution TIC « Reply #324 on: November 15, 2019, 01:44:14 pm » Hi guys, To try to solve the mystery with the too fast de-charging of the 1nF cap. And the other is 1000 and 10000 seconds final version. pdf at main · AndrewBCN/Lars-DIY-GPSDO By Lars Walenius, Aug 11, 2017 This is a flexible GPSDO (GPS Disciplined Oscillator) controller mainly for the experimenter and will work as a complete GPSDO with a GPS receiver that can output 1PPS (pulse per second) and a 10MHz VCO (voltage controlled oscillator). 000 078 Hz and a mean value of 10,000,000. 10 ns (?) RMS accuracy Apparently Lars was the only member of his family with any interest in electronics, and I believe he wanted other electronics hobbyists to have full access to his project, this is why putting the project under an Open Source license while retaining Lars Walenius copyrights seems the right thing to do. pdf" I also included the Centroid files for both sides, they have the . 7V) compared to the Schottky diode (around 0. 1 fork. Aug 8, 2021 · In Lars' GPSDO and the STM32 GPSDO, this is a constant defined at compile time, in Erik's GPSDO this is a variable that "adapts" to the stability of the TCXO. 096V shunt. Apr 30, 2022 · I have a different opinion about this. I provide two hex code ready to use. 35x10 5 seconds occurred when I fired up my 100 watt HF transmitter in close proximity ). 8V is also sent to the line driver/receiver system. Sep 14, 2020 · Instead of using the 78L08 as the basis for the 4V OCXO reference voltage divider, I'm now using an LM4040 4. Four main components make up the GPSDO – the GPS receiver, the reference oscillator, the time measurement system, and the control system. \nIt also implements a PID based fan controller for the ambient temperature of the PGSDO enclosure itself. Aug 12, 2023 · The reason I bring this up is because I started a project last year to see if I could build a counter that could measure my main GPSDO, that is based on small improvements on the Lars design. In this mode the Lars GPSDO is used to calculate ADEVs while the main display is the GPS info. I think, however, that it only connects to the GPSDO command console and not to the GPS receiver at the same time so it may not be as useful. The PDFs contain all you need to know about setting up the GPSDO. 8V wall wart, the board supply is via a 7805. 01 ppb (1e-11). eevblog. I already had ideas to upgrade my current GPSDO (Version 1, described here) a long time ago, just never got around to it. A 10 MHz ISOTEMP OCXO 134-10 is divided down to 10 kHz and phase locked to this GPS signal. When using an analog hardware control loop as in the Miller design and various old commercial GPSDOs, changing the corner frequency of the low pass filter requires changing an onboard GPSDO YT 10 Mhz Lcd 2x16 With LED, UTC Time and GPS Localisation. 0 with a solid lock. Dec 29, 2018 · I think the biggest favor we could do for Lars is learn from his design and postings and refine his GPSDO/TIC design while keeping it affordable to all. Jul 21, 2021 · Lars' documentation provides an algorithm to find an empirical "optimal" value for the control loop time constant for T-Lars, your algorithm automates the task of monotonically increasing the initial time variable T-Erik up to some empirical stable time interval T-Erik(Max) where the measured phase difference is above some arbitrary value. I think what you can safely conclude from the graphs is that the whole system with the Bliley OCXO is the most stable of them, since the MDEV graph basically shows that the control loop has to do much less "work" to keep the OCXO locked. Antenna is a roof mounted “mushroom” type. It works fine, and with the box it is even a bit more stable, I think because of the OCXO temperature being more stable. vscode","path":"fw/lars-code-improved/. : February 08 2023 , Last version is 1. The visible ringing is due to a mismatch between the low impedance output of the OCXO and the high impedance of the 10x scope probe, but it doesn't affect the stability of the GPSDO one bit (or one Hz, I could say). Fig. Time gate is in hexadecimal. I ported it to PIC (PIC18F27Q84). 1 star. I have almost all the parts already, with the exception of the OCXO. Jul 26, 2019 · There is a thread somewhere with the XOR PLL I did with my GPSDO. Time lapse 30x or 82 mins total duration. ) Logged Readers discretion is advised. Hi Andrew. Jul 19, 2020 · I am thinking about building Lars's gpsdo in part so I can a second point of reference, to evaluate my surplus telcom GPSDO, and also because. 2 Nov 4, 2018 · However- my TP GPSDO's and its GPSDO controller's current home is still inside a plain white cardboard box, with the holes for jacks and wires cut out of it. GPS for global positioning system. 2 These are the original files for Lars' DIY GPSDO EEVblog project by Lars Walenius - Lars-DIY-GPSDO/README. pdf at main · paulvee/Lars-GPSDO-V4. The Q&A documents is called "QA for BOM 10MHz GPSDO V4. Jan 26, 2023 · Here's another variant of the Lars GPSDO. ldi r31,high(data7*2) ;" Lars DIY GPSDO " Ici on va chercher l'addresse mémoire ou se retrouve le data à afficher. Jun 15, 2020 · If you look in the original pdf from Lars, it shows the TL graphs that I referred to. The Sprint 6 layout. On page 3 of Lars' PDF documentation you have the correct plot for a few of his GPSDOs, which I am attaching. com/forum/projects/lars-diy-gpsdo-with-arduino-and-1ns-resolution-tic/ What is Lars Arduino based GPSDO Controller with 1ns resolution TIC? This is a flexible GPSDO (GPS Disciplined Oscillator) controller mainly for the experimenter and will work as a complete GPSDO with a GPS receiver that can output 1PPS (pulse per second) and a 10MHz VCO (voltage controlled oscillator). To use this mode use the /ei=port /itl command line options. The version of the Arduino code I use (gpsdo_V3_64) is a modified one from Lars' original to be able to use the circuit without the 1Mohm discharge resistor. Contribute to W3AXL/Simple-GPSDO development by creating an account on GitHub. Because part of the reason I am interested in the project is "affordable science" I dont want to spend a lot on the OCXO. Used NEO7 and 10kHz and then tried with 20 and 40KHz. 5pF) type. Regular Contributor; Posts: 130; Country: I'm very pleased with my Lars GPSDO, it stayed This is a significant improvement to the first version - Lars-GPSDO-V4. Files for my Lars GPSDO project. Unfortunately, no documentation. pdf", check the first post. Instead of the 1N5711 Schottky diode that Lars recommended, I'm now switching to a BAV199 (2pF) or a BAV99 (1. Feb 8, 2021 · @MIS42N I meant to explain the scope traces - sorry! I'm triggering from CH1 (yellow trace) which is monitoring the GPSDO's 10MHz output. 2/ibom. Oct 16, 2018 · So what that graph is, I finally understood myself , it is what Lars said, the DAC captured in the third numeric field from the Arduino serial multiplied by 2E-12 which in Lars's example with a gain of 500 and 130ppb range is the correct Hz/bit but in my case with a gain of 120 and a range of about 546ppb iiiiisss not Aug 5, 2021 · In Lars' GPSDO and the STM32 GPSDO, this is a constant defined at compile time, in Erik's GPSDO this is a variable that "adapts" to the stability of the TCXO. Watchers. T h e Z L 1 B P U Ve r s i o n. Notes to accompany board layout for the Lars Walenius and Murray Greenman GPSDO PCB based on Lars GPSDO published in the EEVBlog forum - Qw3rtzuiop/Lars-GPSDO-PCB The version of the Arduino code I use (gpsdo_V3_70) is a modified one from Lars' original to be able to use the circuit without the 1Mohm discharge resistor. Sorry if they are a bit basic I insulated my OCXO with closed cell foam and ran the GPSDO for 5 days, results below. he captures the Timer1 value at the beginning of the 1PPS ISR, he uses "timer_us" variable for "timer1 value in microseconds offset from 1pps"). I have built several complete GPSDO prototypes to test both Jul 18, 2021 · 1. I once checked with Temex about their FRS series and was told that the analogue C-field adjustment was truly analogue and step-less, but neither of the two old Temex ones that I tried worked brilliantly. This code is This serial port allows me to monitor GPSDO operation and change, on the fly, various parameters without having to first plug an Arduino Development cable into the Arduino board (plugging this cable into the Arduino board causes the Arduino to re-initialize -- an action I usually don't want to have happen if I simply want to monitor the GPSDO a derivative of Lar's Arduino GPSDO. Mar 21, 2022 · The assumption here is that this would prevent the voltage to the AVR ADC from exceeding 1. It should still lock if you use a small enough time constant. Contribute to paulvee/Lars-GPSDO-V1 development by creating an account on GitHub. When using an analog hardware control loop as in the Miller design and various old commercial GPSDOs, changing the corner frequency of the low pass filter requires changing an onboard Nov 26, 2019 · Hi, inspired by the discussion on Lars DIY GPSDO, I went on to try a different, slightly more elaborate approach on the topic. e. 25V). Aug 28, 2023 · The setup is: Lars Wilenius GPSDO with an NEC Toyocom TCO-6703N 10 MHz ovened osc. Lars \n. I don't have one to refine the support. The Lars GPSDO appears to be accurate (assuming the clock is still on frequency) with a median value of 10,000,000. Jun 24, 2023 · To reduce the temperature effects a bit, I already switched to using a Mica capacitor used in the Phase-diff circuit. The pulse width can be down to 10uS and probably even shorter. 14 beta version (and I believe earlier versions, too) support the "Lars GPSDO" to some extent. Nov 21, 2020 · I have some questions for the experts please. My approach has one main difference: instead of using external ICs (4046 and HC390) to divide the 10 MHz to 1MHz and measure the phase difference, I implemented those functions using PIC Configurable Logic Cells (CLC). Frankly, I am still indecisive about how I want to implement it. ldi r30,low(data7*2) ;Load adress of message in Z register rcall message Oct 25, 2020 · GPSDO TC_1000. Block diagram of a typical GPSDO The GPS Receiver The TimeLab software used to generate this graph is free, and the Lars' GPSDO code sends data in a format that the program can readily use. Oct 5, 2020 · Hi Neal, Q#1: I use two choke filters. I found a few very promising reciprocal counter designs from a developer (Michael Nowak) that is also published on this Forum, and started to experiment Feb 25, 2022 · In Lars' GPSDO design, the 1ns refers to the theoretical resolution of the phase detector in the PLL (phase-locked-loop), not to the duration of the 1PPS pulse from Mar 10, 2021 · Hi, I have undertaken the long term project of refactoring Lars' code / Arduino sketch for his GPSDO. Nov 7, 2021 · Note that you may find that the 32u4 and similarly the original 328P 8-bit, 16MHz MCUs simply do not have enough flash and/or processing power to simultaneously monitor the GPS and run Lars' GPSDO code, using for example the TinyGPS++ library. This is a significant improvement to the first version - Lars-GPSDO-V4. dzpd oygd vjvuxsp ypccnw duzynx slphkaoc mktyiak mmvs qawkvt lxydxfa