HamGeek uSOTA-ATU USDX HF QRP SDR Transceiver Built-in ATU-100 Antenna Tuner with Dual OLED Displays

uSDX_ATU:
1. uSDX: HF QRP SDR Transceiver
uSDX is optimized and modified based on Guido PE1NNZ's open source project uSDX/QCX-SSB. uSDX is a shortwave QRP SSB/CW transceiver. With 1602 LCD screen and ultra-small size, it is easy to carry.

Open source address: https://github.com/threeme3/QCX-SSB
Discussion group: https://groups.io/g/ucx/topics

2. ATU: (Automatic Antenna Tuner Unit):
Automatic Antenna Tuner Unit is a miniaturized clone of David Fainitski, N7DDC’s infamous 7X7 ATU100 automatic antenna tuner unit adapted for QRP operation up to 10 watts.

uSDX_ATU Performance Characteristics:
1. uSDX:
- 8 bands: 3.5MHz; 5.3MHz; 7MHz; 10MHz; 14MHz; 18MHz; 21MHz; 29MHz
- Emission efficiency: higher than 85% ( 3.5MHz; 5.3MHz; 7MHz; 10MHz; 14MHz); higher than 80% (18MHz and 21MHz); higher than 70% for 29MHz
- Connect to PC, use FT8, JS8, FT4 and other digital mode software control, support CW automatic decoding
- It can reach 3-5W power in 8 bands and can freely upgrade the PA module (TO-220)
- High-precision TCXO for KDS, frequency accuracy better than 1PPM, frequency stability better than 0.5PPM
- Independent core board, RF PA board and ATU board to avoid own signal interference
- Ultra-small size: 100 x 90 x 57mm/3.9 x 3.5 x 2.2" (without protrusions)
- All LPF parts use 100V C0G/NP0 capacitors
- Use original LM4562 or LM833 or LT6231 op amp chip
- Rich interfaces: HEADPHONE, PTT OUT, MIC/PTT, SPK/MIC
- BNC antenna interface (with BCN-SL16 adapter, easy to match antenna)
- External power supply: 12.6VDC (13.8VDC power adapter)

2. ATU:
- Maximum tuning inductance: 8.42µH
- Minimum tuning inductance: 0.05μH
- Maximum tuning capacitance: 1869pF
- Minimum tuning capacitance: 10pF

uSDX_ATU System Functions:
- Full mode support: USB, LSB, CW, AM, FM
- All-digital and software-based SDR receive channels
- All-digital and software-based SSB transmit channels
- Receive attenuator: 0dB, -13dB, -20dB, -33dB, -53dB, -60dB, and -73dB
- DSP filter bandwidths: 4000, 2500, 1700, 500, 200, 100, and 50 Hz
- Receiving background noise: –135dBm at 28MHz (BW=200Hz)
- Receiver Front-End selectivity: Tuning frequency -45dB/decade roll-off +/- 2kHz
- SSB/carrier suppression: transmit, better than 45dBc; receive, better than 50dBc
- DSP functions: Automatic Gain Control (AGC), Noise Reduction (NR), Voice Triggered Xmit (VOX), RX Attenuator (ATT), TX Noise Gate, TX Drive Control, Volume Control, dBm/S meter

Three-Layer PCB:
- ATU-board
- PA-board: 8 band
- Mainboard

Rear Panel Connector (JACK):
1. Headphone Jack (3.5 mm):
Tip–Audio out
Ring–Audio out
Sleep–GND

2. MIC/PTT (KEY) Jack (3.5 mm):
Tip–Mic input
Ring–PTT
Sleep–GND

CW-KEY INPUT MODE:
Tip–DAH
Ring–DIT
Sleep–GND

3. SPK/MIC Jack (3.5 mm):
TIP: SPEAKER
RING 1: MIC
RING 2: PTT
SLEEVE: GND

4. PTT OUT Jack (3.5 mm):
Tip–SSR output
Ring–SSR output
Sleep–GND

Package Included:
- 1 x Main Unit uSDX_ATU
- 1 x 12.6VDC Power Adapter (or 13.8VDC)
- 1 x BNC-SL16 Adapter
- 1 x BNC-BNC Cable
- 1 x UV-3R Handheld Microphone (including MIC, PTT, SPEAKER functions)

Note:
- Note that there is no built-in battery or built-in speaker. External power supply 13.6v is required.