/pico_jjy_tx

JJY transmitter for Raspberry Pi Pico W

Primary LanguagePythonGNU General Public License v3.0GPL-3.0

JJY transmitter for Raspberry Pi Pico W

Overview

This project is JJY transmitter for Raspberry Pi Pico W in proximate usage

This project supports:

  • Fetch JST time by NTP
  • Generate JJY signal
  • JJY carrier frequency is configurable for 40 KHz or 60 KHz

About JJY, please refer to https://jjy.nict.go.jp/jjy/trans/index.html

Supported Board

  • Raspberry Pi Pico W

Pin Assignment

Pico Pin # Pin Name Function Note
3 GND GND Ground
4 GP2 PIN_MOD_P JJY modulation differential output Pch
5 GP3 PIN_MOD_N JJY modulation differential output Nch
6 GP4 PIN_CTRL Control Output (option for external carrier generator)
  • If single-ended output is required, use GP2 and GND.

Connection Diagram

Connection Diagram

How to make the program work

  • Use Thonny or similar MicroPython IDE (Confirmed with Thonny 4.0.2, Python 3.10.9)
  • Install MicroPython (Raspberry Pi Pico) interpreter firmware on Raspberry Pi Pico W by Thonny
  • Confirmed with MicroPython v1.22.2
  • Add secrets.py to include your WiFi configuration and put it on the storage of Raspberry Pi Pico W
# secrets.py
secrets = {
  'ssid': 'xxxx',
  'password': 'xxxx',
}
  • Excecute pico_jjy_tx.py from Thonny
  • For stand-alone application, please rename pico_jjy_tx.py as main.py and store in the storage of Raspberry Pi Pico W

Tips for emitting JJY

  • The easiest way to make the clock detect JJY emulated singal in small room environment, is just to connect wired earphone between PIN_MOD_P and PIN_MOD_N pins and put the clock near the earphone cable. (This could damage the earphone. please try with cheaper one.)
  • For the more proper way, round ferrite rod bar antenna with appropriate driver would be suitable.