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How to use GPS module for real-time location and PPS clock synchronization service
ICP DAS GPS-721 GPS Receiver and 1 DO, 1 PPS Output Module communicable Over RS-232 and RS-485.
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Raspberry Pi GPS Module USB Port – Kuongshun Electronic Shop
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VK-162 G-Mouse - Remote Mount USB - External GPS Navigation Dongle - Supports Stratux, Raspberry Pi, - YouTube
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GPS-DO expansion board GPS input PPS and 10MHz output port USB PC | eBay
Adafruit Ultimate GPS GNSS with USB - 99 channel w/10 Hz updates : ID 4279 : $29.95 : Adafruit Industries, Unique & fun DIY electronics and kits
Frontiers | Time Synchronization for Wireless Sensors Using Low-Cost GPS Module and Arduino
z050 USB GPS Dongle with PPS - ZTI
Time Server
USB GPS Module – ODROID
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PPS over USB
USB GPS Module – ODROID
Microsecond accurate NTP with a Raspberry Pi and PPS GPS - Austin's Nerdy Things
Adding PPS to a cheap USB GPS stick | Brendan's Radio Blog
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