ADX-POCKET — Shirt-Pocket Digital Modes HF Transceiver with CAT Control
Ultra-compact dual-board ADX variant by WB2CBA integrating USB hub, sound card, serial CAT control, and ATmega328P on a single controller board. Operates at 700mW from USB or up to 5W with external 12V power.
Overview
The ADX-POCKET is a miniaturized version of the ADX digital transceiver by WB2CBA that fits in a shirt pocket. It uses a two-board stacking design — a controller board with integrated USB hub, USB-to-serial converter, ATmega328P microcontroller, and CM108 USB sound card, topped by an RF transceiver board containing all the analog radio circuitry.
Key Features
- Single USB connection for sound card audio and CAT control
- Dual power modes:
- USB-powered QRPp mode: ~700mW from 5V USB
- External DC (10-12V): up to 5W QRP output
- Integrated USB hub with USB sound card (CM108) and USB-to-serial converter
- CAT control emulating Kenwood TS-2000 (9600 bps serial)
- Dual interface: classic buttons/LEDs or full CAT control via WSJT-X
Supported Modes and Bands
- Digital Modes: FT8, FT4, JS8Call, and WSPR
- Bands: 80m, 40m, 30m, 20m, 17m, 15m, and 10m via interchangeable LPF modules
Architecture
The two-board design separates concerns cleanly:
- Controller Board: USB hub, USB-to-serial, ATmega328P/AU MCU, CM108 USB sound card
- RF Board: Complete ADX transceiver RF section (CD2003GP receiver, Si5351 VFO, Class-E PA)
The boards stack vertically using pin headers, creating an extremely compact package while maintaining full ADX transceiver capability.
Operation
Can be operated in two modes:
- Classic mode: Physical buttons and LED indicators for standalone use
- CAT mode: Full computer control via WSJT-X with automatic band and mode switching
The ADX-POCKET is fully open source with PCB gerbers, firmware, and build documentation available on GitHub.
