AMNVOLT V4 ATS MINI SI4732 Radio ALL Band DSP Radio FM AM SSB LSB USB Receiver Built-in Hi-Z Headphone Amplifier Circuit

the blow pictures, which shows how to check thehardware info on the firmware system-information screen.Basic Function Specifications:1. The main control uses ESP32-S3, combined with the SI4732 DSP chip, supporting AM/FM and LSB/USB modes, and featuring AGC/ATT functions.2. Equipped with a 1.9-inch IPS color screen (resolution 170×320), it supports backlight brightness adjustment (32~255 levels), and can display battery level.3. Built-in 1W cavity speaker, with clear output volume.4. Supports firmware upgrade. The factory firmware version is not lower than VER.2.3.1. Due to the frequent firmware updates, it is recommended that users upgrade to the latest version after receiving it according to the instructions to obtain a better user experience.5. Built-in headphone amplifier circuit, providing sufficient output amplitude when listening with headphones.6. Built-in high-impedance input stage, used to enhance weak signal reception capability.7. The main control module is recommended to use the original ESP32-S3-WROOM-1-N16R8. Non-original or counterfeit modules may have compatibility or performance differences.8. A shielding cover was added to the Si4732 receiving circuit section to reduce electromagnetic interference; ESD protection components were added to the antenna input port to enhance electrostatic protection capability.9. The high-resistance input circuit was adjusted to the front end of the antenna signal path and was powered independently by VCC_RADIO to maintain signal resonance stability and help reduce background noise.10. A new feature has been added to support the use of wired headphones as an FM antenna. Note: The headphones are not included with the product and must be provided by the user; this method is effective only in environments with strong FM signals, and the longer the headphone cable, the better the reception effect.11. The left and right channel outputs have been swapped; at the same time, the matching parameters of the power amplifier and the speaker have been redefined to optimize the overall listening experience.12. Some peripheral components have been replaced with models that are more cost-effective and more durable: The telescopic antenna structure has been strengthened, and the knob cover has been changed to a non-slip design, providing a more comfortable feel.13. The motherboard hardware is natively compatible with the third-party firmware developed by H.J.Berndt, and no soldering or jumper modifications are required for the motherboard. The official firmware is pre-installed by default on the factory, and users can manually upgrade to the H.J.Berndt version if needed. This firmware additionally supports RTTY/CW decoding and other functions. Note that the device is not pre-installed with this third-party firmware at the time of shipment.Main parameters:- Brand: AMNVOLT- Main : ESP32-S3- Working mode: FM / AM / LSB / USB (does not support aviation frequency band)- Reception frequency range:- LW / MW / SW: 150kHz ~ 30MHz- VHF: 64 ~ 108MHz- Screen: 1.9 inches, resolution 170×320- Backlight brightness adjustment range: 32 ~ 255 levels- Charging interface: USB Type-C (does not support fast charging protocol charger)- Audio interface: 3.5mm three-section stereo socket- Antenna interface: SMA-KE (inner hole type)- Battery capacity: 800mAh- Shell material options: Two versions of shells are available for selection: metal and ABS injection molding.Packaging List:- AMNVOLT V4 Digital Receiver × 1- Extendable Rod Antenna × 1- Rotating Circular Antenna × 1Precautions before purchase:1. The version with metal casing has an aluminum alloy material which can provide some shielding against electromagnetic waves, which may help reduce some external interference. However, it will also weaken the Wi-Fi signal reception strength. Please make an appropriate choice based on the usage environment.2. The headphones are an optional accessory and are not included in the package. The headphones shown in the picture are only for illustrating the FM antenna function. Users are required to prepare them themselves.