ntp NTP server frequency stability Stratum 2+ NTP servers have multiple potential sources of error, let's experiment with lowering them.
TCXO TCXO RTC Raspberry Pi Hat, part 2 The motivation for this project is NTP servers in datacenters - it can be expensive to get a GPS antenna on top of other people's buildings with a wire running down into your
ntp TCXO RTC Raspberry Pi Hat History I'm bringing my RTC Hats [https://blog.dan.drown.org/tag/stratum2/] back online (source code [https://github.com/ddrown/stm32-input-capture-f031] and hardware design [https://github.com/ddrown/stm32-input-capture-f031/tree/master/hardware]
stratum2 Drift One of my goals with the RTC Pi Hats [https://blog.dan.drown.org/tag/stratum2/] was to have a more stable local frequency. This is useful when you can't reach your upstream
ntp TCXO RTC Hats: aging & RTC frequency I'm focusing on oscillator aging and RTC frequency in this post. See also: initial data [https://blog.dan.drown.org/tcxo-rtc-hats-initial-data/], picture [https://blog.dan.drown.org/tcxo-rtc-hats/], other stratum 2 posts [https:
ntp TCXO RTC Hats: Initial data The TCXO RTC hats [https://blog.dan.drown.org/tcxo-rtc-hats/] are collecting data. I'm focusing on the RTC part in this post. See also: other stratum 2 posts [https://blog.dan.drown.org/
ntp TCXO RTC Hats My new stratum 2 NTP server hats arrived from Macrofab today! I have a few hand soldering things to do (32khz crystal and headers), and then I can start calibrating them.
time Temperature compensation, part 2 In the last part [https://blog.dan.drown.org/temperature-compensation/], I measured the TCXO to fit a frequency vs temperature curve. Frequency vs Temperature curve Below are the final curves that I went
time Temperature compensation Temperature effects are usually the largest source of frequency changes in clocks. So I have three temperature sensors on my test system [https://blog.dan.drown.org/frequency-synchronization-without-phase-in-ntp/]. The sensors are: one built
time Frequency synchronization without phase in NTP I've been working on my high accuracy RTC project [https://blog.dan.drown.org/stm32f030-devboard-with-tcxo/]. Here's a picture of one of the two systems: Connections The TCXO devboard, BME280, and PCF RTC are
stm32 stm32f030 devboard with TCXO I'm interested in making a high accuracy real time clock (RTC). To experiment with the hardware I need for that, I created a development board based on the STM32F030F4P6 (which is a 20-TSSOP