A simple and easy WiFi-enabled ESP8266-powered WSPR and FT8 beacon which uses NTP + DS3231 RTC for timing.

Easy-Digital-Beacons-v1

A simple and easy WiFi-enabled ESP8266-powered WSPR and FT8 beacon which uses NTP + DS3231 RTC for timing.

The whole design is modular, field repairable, and super extensible. It is almost trivial to add support for more beacon modes.

The DT timings are very nice with NTP Sync, DS3231 RTC and the optional time-delta hack.

WSPR mode demo:

Beacon's web interface:

Sample 3D rendering:

Note: This 3D rendering is only published to help with the manual layout work on Zero-PCBs.

Si5351A module is connected via I2C to pins D1 (SCL) and D2 (SDA) of the Wemos D1 Mini board. Connect DS3231 similarly.

Note: See this schematic for details.

Build Steps

git clone https://github.com/kholia/Easy-Digital-Beacons-v1.git
make deps

cd ~/Arduino/libraries
git clone https://github.com/me-no-dev/ESPAsyncWebServer.git
git clone https://github.com/me-no-dev/ESPAsyncTCP.git

Add your WiFi credentials in credentials.h file

Notes

This will need a HF PA in most cases to be usable on the air.

(July-2021 Update): We are working on a more robust HF PA system.

See https://github.com/kholia/HF-PA-v2/tree/main/Images for sample images ;)

No end-user support is provided.

BOM

• 1 x 3/5mm LED (purple or pink is recommended)

• 1 x small regular (spst) chassis mount switch

• 1 x 0.25w 470 ohm resistor (CFR / MFR)

• Relimate male connectors

• Relimate female-female cables

• Female berg strips

• Zero PCB of a suitable size

Si5351A Module:

DS3231 RTC Module:

μC Board:

BOM Sources

• https://robu.in/

• https://www.electronicscomp.com/

• https://projectpoint.in/

Tips

Useful commands:

pacmd load-module module-null-sink sink_name=Virtual0
pacmd update-sink-proplist Virtual0 device.description=Virtual0
pacmd update-source-proplist Virtual0.monitor device.description=Virtual0

Use Gqrx and WSJT-X with a SDR device for initial frequency adjustment / calibration. This is essential for WSPR functionality. FT8 is more robust/tolerant of frequency deviations due to a much larger RX window.

Future Tasks

• EEPROM - save TX interval / schedule

• Add support for custom FT8 messages

• Re-announce mDNS stuff

• Change Si5351 calibration factor

• Make time-delta hack optional

• Reset to defaults button

References + Credits

• https://github.com/kgoba/ft8_lib

• https://github.com/etherkit/JTEncode

• https://github.com/Naguissa/uEEPROMLib

• https://randomnerdtutorials.com/esp8266-web-server-spiffs-nodemcu/

• https://lastminuteengineers.com/ds3231-rtc-arduino-tutorial/

• https://learn.adafruit.com/adafruit-si5351-clock-generator-breakout/wiring-and-test