Techno Keyer is an autonomous CW (continuous wave) keyer with encode/decode abilities for amateur radio (ham radio) enthusiasts to send out morse codes with USB keyboards.
ℹ ️ This repository only contains firmware implementation of Techno Keyer. The hardware design and schematics are not included.
The design of Techno Keyer comes with a VFD (vacuum fluorescent display) module, which makes it feels more like other vintage electronic devices from 1980s. Because of this idea, the word "Techno" seems to be a good fit for naming this project.
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Dimension: 115mm (W) x 52mm (D) x 45mm (H)
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Display
- 16x2 VFD display for messages and status.
- Blue LED for CW key output status.
- Red LED for audio input status.
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TX Mode
- Transmit morse code by input form USB keyboard.
- Work as a straight key by the 3.5mm key port.
- Display input messages on VFD before sending out.
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RX Mode
- Receive morse code (CW) audio signal from radio or other source.
- Decode and display messages received on VFD.
- Select specific pitch frequency for audio input.
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Configurable
- Set CW speed (10-50 WPM) for transmitting.
- Set VFD brightness.
- Set pitch frequency (400-1000Hz) for buzzer output (TX & RX mode).
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Power On
- Connect USB Type-C cable to power the Techno Keyer on.
- The VFD will display the welcome message.
- After 2 seconds, the keyer will enter the transmit (TX) mode.
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Send Morse Code
- Plug USB keyboard to the Type-A port.
- Connect radio to the 3.5mm key port, set key mode as straight key.
- Use the USB keyboard to input messages.
- Press Enter or Space key to send out the message in morse code.
- Press Backspace key to retract the last word.
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Decode Audio Input
- Connect audio source to the 3.5mm audio input jack.
- Rotate the rotary encoder to adjust the centering pitch frequency.
- The Techno Keyer will decode morse code from audio signal matching target pitch frequency automatically.
- The decoded messages will be displayed on the VFD, and the Techno Keyer would entering the receive (RX) mode.
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Config Settings
- Press the rotary encoder button to enter the configuration mode.
- Press the encoder button again to select the setting to change.
- Rotate the encoder to change value of selected setting.
- The settings include:
- VFD brightness (0-100%)
- TX Speed - CW speed for transmit mode (10-50 WPM)
- TX Tone - Pitch frequency for transmit mode (400-1000Hz)
- RX Tone - Pitch frequency for receive mode (400-1000Hz)
- After configuring the last menu item, press the encoder button to save and exit the configuration mode, all changes made would be saved.
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Other Functions
- The buzzer could be turned off by the switch beside the USB type-C port.
- Press the rotary encoder button for 3 seconds to restart the keyer.
ℹ ️ Note:
- If TX mode is active, the audio input will be blocked for 3 seconds after sending out the last character.
- If RX mode is active, the keyboard input will be blocked for 3 seconds.
- Developed with PlatformIO and Arduino framework.
- Platform:
esp32-s3 - Libraries:
- ESP32-S3-WROOM-1 module as main MCU
- CIG25-1605N VFD module
- Rotary encoder
- Solid state relay (TLP175A) for CW key control
- LM567 tone decoder
- CH9350 USB keyboard & mouse communication control chip
- Passive Buzzer with one switch to turn it off
- 3.5mm key port
- 3.5mm audio input jack
- USB Type-A keyboard input port
- USB Type-C port for power supply and serial communication
Pins used by ESP32-S3-WROOM-1 module for Techno Keyer.
| GPIO | Description |
|---|---|
| 12 | SPI clock |
| 11 | SPI data out (MOSI) |
| 21 | SPI chip select for pitch tuning potentiometer |
| 10 | SPI chip select for VFD |
| 17 | VFD enable |
| 18 | VFD reset |
| 15 | Keyboard data receive (RX) |
| 16 | Keyboard data transmit (TX) |
| 5 | Rotary encoder A |
| 6 | Rotary encoder B |
| 7 | Rotary encoder button |
| 14 | CW (morse code) signal output |
| 2 | Buzzer output |
| 8 | Audio signal input |
- Morserino-32
- K45B CW Modem w/USB Keyboard I/F
- K4ICY's CW Morse Decoder
- wb7fhc-cw-decoder
- VK2IDL_CW_Decoder
Designed by BD4WEI. Build on 🌍 with 💓.