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# SparkPNT GNSS Disciplined Oscillator

**Type:** Product page · **SKU:** GPS-26289 · **Brand:** [Sparkfun](https://core-electronics.com.au/brands/sparkfun-australia)
**Page:** https://core-electronics.com.au/sparkfun-gnss-disciplined-oscillator-high-precision-timing.html ([markdown](https://core-electronics.com.au/sparkfun-gnss-disciplined-oscillator-high-precision-timing.html.md))

Designed and manufactured in Boulder, Colorado, USA, the SparkPNT GNSS Disciplined Oscillator (GNSSDO) is the perfect solution for your high-precision...

## Pricing

- **Price:** $3,895.00 (inc GST) — $3,540.91 AUD, exc GST
- **Quantity discounts:** 5+ $3434.68 (exc GST) · 25+ $3363.86 (exc GST) · 100+ $3222.23 (exc GST)

## Availability & dispatch

- Available with a lead time — expect dispatch between Aug 17 and Aug 24.

## How to buy

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## Description

Designed and manufactured in Boulder, Colorado, USA, the SparkPNT GNSS Disciplined Oscillator (GNSSDO) is the perfect solution for your high-precision timing and frequency needs. This is our most advanced timing product based on the multi-constellation, multi-frequency, L1/L2/L5-ready mosaic-T from Septentrio.

The Septentrio mosaic-T offers a high-precision solution for time and frequency synchronization under challenging conditions, such as during GNSS jamming or spoofing. It provides unmatched resilience thanks to its all-constellation multi-frequency capabilities and AIM+ technology. Time pulse precision is 5ns, and better than 1 nanosecond with an optional [subscription to Fugro AtomiChron®](https://sparkfun.com/gnssdo_registration). Event accuracy is better than 20ns. We've paired the mosaic-T with the SiT5358 Super-TCXO from SiTime to provide the best clock frequency stability, accuracy, and holdover during GNSS outage. Are you looking for a very accurate time and frequency solution for your lab or remote equipment? This is it!

Under the hood, the GNSSDO is based on the mosaic-T GNSS module from Septentrio, plus the Espressif ESP32-WROVER processor (16MB flash, 8MB PSRAM). The disciplined 10MHz oscillator is the SiT5358 Super-TCXO from SiTime: ±50ppb stability; ±1ppb/°C frequency slope; ±58ppb typical 20-year aging; with digital control via I²C; the [Allan Deviation](https://core-electronics.com.au/attachments/localcontent/Allan_Deviation_1017476d4ad.jpg) approaches 1E-14 at 10000 seconds with AtomiChron® enabled. The mosaic-T has USB-C connectivity (with Ethernet-over-USB) and multiple UARTs, and it supports full Ethernet connectivity. You can connect the mosaic-T directly to your Ethernet network - our product supports Power-over-Ethernet too. The ESP32 is there to discipline the TCXO and control the OLED display. Remote configuration is easy, thanks to your access to the internal ESP32 serial console via TCP.

We've designed the GNSSDO to be robust and deployable. Internally, all electronics (except the Qwiic OLED display) are mounted on a single circuit board. The mosaic-T GNSS antenna, Pulse-Per-Second output, disciplined 10MHz output, and EventA input are all connected via SMA connectors. If desired, the 10MHz SMA can also be configured as an input, allowing you to use your own TCXO. IO connections are made via a 3.5mm header with cage screw connections. The IO voltage is selectable between 3.3V and 5V. The Reset and Log switches have been positioned carefully; Log is easily clicked when required, and Reset is flush and needs a more assertive press. The edge of the microSD card protrudes slightly when inserted, making it easy to eject and re-insert. Then there is the beautiful custom extruded aluminum case with machined end panels and slotted flanges, making it simple to install the GNSSDO in a weatherproof enclosure up on the roof or in your server rack.

The included antenna has been certified by the National Geodetic Survey. The [ANTEX](https://geodesy.noaa.gov/ANTCAL/LoadFile?file=SFESPK6618H_NONE.atx) and [ANTINFO](https://geodesy.noaa.gov/ANTCAL/LoadFile?file=SFESPK6618H_NONE.003) are available. The full listing under **SFESPK6618H** is on the [NGS Antenna Calibrations](https://geodesy.noaa.gov/ANTCAL/)website. AtomiChron® service is delivered over-the-air using the same GNSS antenna that is provided with the kit, no internet access is required.

The GNSSDO has multiple power options. Any or all of these can power it: the mosaic-T USB-C connection, the ESP32 USB-C connection, Power-over-Ethernet (36V to 57V), or an external DC power source between 9V and 36V. The GNSS SMA antenna connection provides 3.3V for the included active L1/L2/L5 antenna.

Our kit includes everything you need to get up and running. Please see the 'Includes' tab for more information.

**Please Note:** the mosaic-T firmware (4.14.4) supports RTCM input for RTK Rover positioning. However, **RTCM output is not supported**. You cannot use the mosaic-T as a RTK Base. The documentation suggests you can, but, sadly, you cannot.### Features & Specs

| MODULE | RECEPTION | CONSTELLATIONS | INTERNAL ANTENNA | COMMUNICATIONS HARDWARE | APPLICATION | CORRECTIONS SOURCE |
|---|---|---|---|---|---|---|
| Septentrio mosaic-T | L1/L2/L5 | GPS, GLONASS, Galileo, BeiDou | No | Ethernet | Timing Source | Fugro AtomiChron® |

### Overall Device Specs

- Designed and manufactured in Boulder, Colorado, USA
- KSZ8041NLI Ethernet PHY interface
    - 10Base-T / 100Base-TX with auto-negotiate and Auto MDI/MDI-X
- microSD socket
    
    - Connected directly to the mosaic-T for fast data logging
- OLED display
    
    - 128x64 pixels
- SMA connections
    
    - GNSS antenna with 3.3V power for an active antenna
    - 10MHz output/input - switchable:
        
        - 10MHz disciplined output (configurable for 5V / 3.3V / 2.8V / 1.8V "CMOS" output and 50 Ohm)
        - 10MHz input (50 Ohm, -14dBm min, +12dBm max)
    - Pulse-Per-Second output (PPSO) (configurable for 5V / 3.3V / 2.8V / 1.8V "CMOS" output and 50 Ohm)
    - EventA input (configurable for 5V / 3.3V / 2.8V / 1.8V and 50 Ohm)
- I/O Connections
    - Robust 3.5mm screw terminals
    - Fully isolated external DC power input (9V - 36V)
    - Switchable 3.3V or 5V I/O voltage
    - mosaic-T COM2 UART: TX, RX, RTS, CTS
    - CTS can be configured as a VCCIO voltage output if needed
        mosaic-T EVENT-B input
    - I²C (SCL2 / SDA2) for an external TCXO
- Custom extruded aluminum case with machined end panels
    
    - Designed to IP42
    - A weatherproof enclosure is required for outdoor use
    - Matte-effect front and rear stickers
- Power options:
    
    - mosaic-T USB-C connector
    - ESP32 USB-C connector
    - Power-over-Ethernet (36V - 57V)
    - DC power input (9V - 36V)

### GNSS Receiver and Oscillator Specs

- Septentrio mosaic-T
    - multi-constellation, multi-frequency GNSS timing receiver
    - Accurate and resilient with dedicated timing features
    - Highly secure against jamming and spoofing with AIM+ unique interference mitigation technology combined with Fugro AtomiChron® services
    - Update rate of 10 Hz
    - 448 hardware channels for simultaneous tracking of all visible supported satellite signals:
        - GPS: L1C/A, L1PY, L2C, L2P, L5
        - GLONASS: L1CA, L2CA, L2P, L3 CDMA
        - Beidou: B1I, B1C, B2a, B2b, B2I, B3
        - Galileo: E1, E5a, E5b, E5 AltBoc, E6
        - QZSS: L1C/A, L1 C/B, L2C, L5
        - NavIC: L5
        - SBAS: Egnos, WAAS, GAGAN, MSAS, SDCM (L1, L5)
        - On-module L-band
    - Supports RTCM input for RTK Rover.**RTCM output (RTK Base) is not supported.**
    - Time pulse precision: 5ns
    - Time pulse precision with AtomiChron® (delivered over L-Band): < 1ns
    - Event accuracy: < 20ns
    - Operating temperature: -40 to 85 °C
    - USB-C interface (UART and Ethernet-over-USB)
- SiT5358 disciplined 10MHz oscillator
    - ±50ppb stability
    - ±1ppb/°C frequency slope
    - ±58ppb typical 20-year aging
    - Digital frequency pulling via I²C
    - [Allan Deviation](https://core-electronics.com.au/attachments/localcontent/Allan_Deviation_1017476d4ad.jpg)approaches 1E-14 at 10000 seconds with AtomiChron® enabled
    - Operating temperature: -40 to 85 °C (Industrial)

### Documentation

**SparkFun GNSSDO**

- [Product Manual](https://docs.sparkfun.com/SparkFun_GNSSDO/)
- [Quick Start Guide](https://core-electronics.com.au/attachments/localcontent/quick_start_guide-v10_371365d7460.pdf)
- [Register for AtomiChron® Subscription](https://sparkfun.com/gnssdo_registration)
- [Schematic](https://core-electronics.com.au/attachments/localcontent/schematic_40001ae4df8.pdf)
- [PCB Dimensions](https://core-electronics.com.au/attachments/localcontent/dimensions_217297d53b3.pdf)
- [Case Dimensions](https://core-electronics.com.au/attachments/localcontent/dimensions-enclosure_355026b3baa.pdf)
- [Hardware GitHub Repo](https://github.com/sparkfun/SparkFun_GNSSDO)
- [ESP32 Firmware](https://github.com/sparkfun/SparkFun_GNSSDO/tree/main/Firmware)
- [Allan Deviation](https://core-electronics.com.au/attachments/localcontent/Allan_Deviation_254703c9675.jpg)

**Septentrio mosaic-T**

- [Septentrio product page](https://www.septentrio.com/en/products/gnss-receivers/gnss-receiver-modules/mosaic-t)
- [Septentrio resources: datasheet, firmware, manual, software tools, USB driver](https://www.septentrio.com/en/products/gnss-receivers/gnss-receiver-modules/mosaic-t#resources)
- [mosaic-T Hardware Manual](https://core-electronics.com.au/attachments/localcontent/mosaic_hardware_manual_v1_3896681e0a5.pdf)
- [mosaic-T Firmware Reference](https://core-electronics.com.au/attachments/localcontent/mosaic-T_Firmware_v4_214232ca390.pdf)

**SiTime SiT5358**

- [Datasheet](https://core-electronics.com.au/attachments/localcontent/SiT5358-datasheet_36594a910a0.pdf)

**Fugro AtomiChron®**

- [Fugro AtomiChron®](https://www.fugro.com/expertise/other-expertise/atomichron)
- [Mastering time: the challenge of time Synchronization](https://www.fugro.com/news/podcasts/2024/mastering-time-the-challenge-of-time-synchronisation)

## Images

- [Product image 1](https://core-electronics.com.au/media/catalog/product/G/P/GPS-26289-1.jpg)