It is a short-wave QRP SSB/CW transmitter-receiver. Portable size is easy to carry and use outdoors, built-in speaker, adopts 1602n LCD screen. It supports connection to computers and using FT8, JS8, FT4 and other digital mode software to control and supports automatic CW decoding. Features: Improved performance: Compared to the old usdx, the new usdx has several improvements: the headphone jack and power/microphone button have been moved to the front panel,to make it easier to connect headphones and power button,Moved buttons to the bottom of the LCD screen for a larger touching area and more comfortable use,The built-in speaker effect has been improved, and the circuit board has reserved pads for various improvements,which can be used as a template to learn DIY updates,It can also quickly change QRP and CW Frequency and support CW side tone volume control. 8 bands include 80m/60m/40m/30m/20m/17m/15m/10m and support all modes: USB, LSB, CW, AM, FM (SSB modes with good reception effect but poor transmission effect. AM and FM are free, but with poor effect. ) It can reach 8 gears of 3-5W and reserve the necessary sot-223 and to-220 pads for upgrades. High emission efficiency: 80m/60m/40m/30m/20m efficiency is more than 80%, 17m efficiency is more than 70%, and 15m/10m efficiency is more than 60%. DSP Functions: Automatic Gain Control (AGC), Noise Reduction (NR), Xmit Voice Trigger (VOX), RX Attenuator (ATT), TX Noise Gate, tx unit control, volume control, dbm/s meter. Open source firmware and allows you to experiment, you can add new features, cartridges can be shared via github, software complexity is 2000 lines of code. Based on VOX software, which can be used as fast Full Break-In (QSK and semi-QSK operation) or RX/TX switching assistance to work in digital modes (PTT interface not required), external PTT output/TX delay PA control. Fully digital and software-based SSB transmission stage: samples the microphone input and reconstructs the SSB signal, controlling the SI5351 PLL phase (through small frequency changes over 800 kbit/s I2C) and PA amplitude (via PWM PA keyforming system). Technical data: Material: aluminum alloy; Power: 13,8 V (max. 1,5 A) Charging: 12,5 V/1 A RF Output Power: 3-5W MDS receiver noise level: -135 dBm at 28MHz (at 200Hz BW) Front-end selectivity receiver: steep drop -45dB/decade ±2kHz from tuned frequency Locking dynamic ranges: offset 20 kHz 123 dB, offset 2 kHz 78 dB Package Weight: 520g/1.1lb List of things to pack: 1 * Transceiver 1 * Microphone