Frequency Calibration via GPS

From Land Boards Wiki
Jump to navigation Jump to search

Inexpensive Frequency Standard with output synchronized to GPS satellites,

Features

  • U-Blox NEO-7M GPS Module
  • Remote Amplified GPS Antenna
    • SMA Male connector
  • FTDI-49MM
    • Used to program the GPS module
  • Pulse Generator modified to provide 50 Ohms, 5V drive
  • Mini-360 Switching Power Supply
  • 5V out
    • 7-23V in

Parts

GPS

NEO-7M-02.PNG

NEO-7M-04.PNG

NEO-7M-05.PNG

  • U-Blox NEO-7M GPS Module
  • SMA Female connector

U-Center Programming Software

FTDI

50 Ohm Driver

  • Used modified PulseGen card to drive 50 Ohms, 5V level output
    • Remove oscillator circuit
    • 5 parallel 74AC14 outputs with 249 ohm resistors on each output
  • Able to drive long 50 ohm coax
  • Square wave output
  • Very fast edges

Videos

  • GPSDO vs Rubidium Frequency Standard