This is a pair of dev boards designed to provide a local stratum 1 GPS based NTP server.

• ESP32-S3-MINI-N4-R2 (Dual CPU, 4M flash, 2M RAM)
• 10/100 Ethernet
• PoE, but can also be powerd by USB-C or DC 5V-28V
• 12 LEDs showing GPS status (number of sats on each network and PPS blink)
• L86 GPS module, with CR2032 battery holder (CR2032 recommended)
• WAGO connectors for connecting cable from main module to GPS

The Ethernet response is typically under 1ms, and typically 0.1ms jitter, allowing very accurate local NTP server for your home or office network.

The power supply flexability is also a key feature, either DC 5V-28V, or USB-C, or PoE. PoE requires the Ag9912-LP module (optional extra).

The 12 LEDs are WS2812, and the supplied code shows them lit in sequence, blue for NAVSTAR(GPS), red for GLONASS, and green for GALILEO, with one LED for each 2 active satellites in use (half brightness for final odd number). The last LED blinks yellow for each PPS on the second.

Unlike some GPS devices, which have a coax to a patch antenna, the GPS module connects via 5 cores to the main board, allowing it to be placed outside. If placing outside, an acrylic spray to protect the PCB is suggested. Solid core cat5 cabling works, but screened cable may be better in some cases. Cable can easily run several metres. You should ensure the GPS module has a good view of the sky for best results.

This a fraction of the price of typical commercial GPS NTP servers. The key differences are the latency - with commercial servers managing 0.1ms, and claiming 10,000 requests per second. This board is around 0.8ms latency usually, and total requests per second have not been measured but presumably under 1000 per second. A typical, even large, business, would not have any where near that many requests per second, so this is ideal as a business time server, but not so much as a high volume NTP pool server. Of course this could work as the main reference for a device that operates as a stratum 2 server, such as a FireBrick, and provide high levels of requests per second.

Supplied with resin 3D printed case for board and for GPS module. You'll need a lead, and solid cat5 is a good choice.

Ethernet should be used for NTP, but this can work over WiFi if you wish - the latency and jitter will not be as good.

MQTT reporting shows status, PPS reliability, requests per second, location, etc.

All parcels shipped with tracked shipping, usually shipped within one working day.