New Features:
From 2026, AMNVOLT V4 hardware natively supports H.J.Berndt firmware without extra soldering or motherboard modifications, and ships with official firmware pre-installed by default.
You need to flash the H.J.Berndt version manually after receiving the unit, and this firmware developed by H.J.Berndt includes functions like RTTY/CW decoding.
V4, V4a, and V4b are simply version batch differences. Batch issues are not covered under warranty. (This information was updated on March 26, 2026.)
Important Note：The device ships with official firmware pre-installed by default. If you need to use the H.J.Berndt version, you need to flash it yourself after receiving the V4 unit.
About this firmware: Developed by H.J.Berndt, this firmware is equipped with multiple functions including RTTY/CW decoding.
V4 Update Content:
1. Added a shield to the Si4732 receiver to suppress electromagnetic interference; Add an ESD device to the antenna input to protect the chip.
2. The Hi-Z circuit has been moved to the front of the antenna path and uses a more stable VCC_RADIO power supply to preserve signal resonance and reduce noise.
3. Use wired headphones as an FM antenna (headphones are not included in the shipping package; this requires use in an environment with a strong FM signal and a long headphone cable for optimal performance).
4. The left and right audio channels have been swapped; the amplifier and speaker parameters have also been retuned to improve sound quality.
5. Replaced with more expensive and superior accessories: telescopic antenna and a non-slip knob cap with a better feel.
Basic Features:
1. Utilizes the ESP32-S3 controller + SI4732 DSP chip, supports all-band broadcasting, LSB USB AM/FM mode, and supports AGC/ATT.
2. 1.9-inch IPS high-definition color screen with adjustable backlight brightness and battery level display.
3. Built-in 1W cavity speaker for loud and pleasant sound quality.
4. Supports the latest firmware upgrade. The factory-installed firmware version is at least VER. 2.3.1. (Due to frequent firmware updates, please update to the latest firmware according to the manual upon receipt to maintain the latest user experience.)
5. Built-in headphone amplifier circuit, ensuring loud volume when listening with headphones.
6. Built-in Hi-Z circuitry improves weak signal resolution.
7. Maintains the original ESP32 module. (ESP32-S3-WROOM-1-N16R8).
Specifications:
- Brand: AMNVOLT
- Model (Hardware Version): V4
- Housing Material: CNC metal or ABS injection molding, two housing materials available
- Controller: ESP-32-S3
- Operating Modes: FM/AM/LSB/USB (Note: Airband is not supported)
- Receiving Bands: HF/SW/MW/VHF
- Frequency Range: LW, MW, SW (150kHz - 30MHz), VHF (64-108MHz)
- Screen: 1.9-inch, 170*320 resolution
- Screen Brightness: Adjustable from 32 to 255 levels
- Charging Port: TYPE-C (Cannot be charged with a fast charger)
- Audio Port: 3.5mm three-way stereo
- Antenna Port: SMA-KE (female)
- Battery Capacity: 800mA
Package Includes:
1 x AMNVOLT V4 Radio
2 x Antenna (Telescopic Antenna/Rotary Antenna)
Notes:
1. Earphones are not included in the shipping list. The earphones in the picture are only for demonstration of the FM antenna function. Please use your own earphones!
2. If you choose the CNC metal housing, the CNC aluminum alloy material has a certain shielding effect on wireless electromagnetic signals. While improving interference reception performance, it may also weaken the Wi-Fi signal connection strength. Please be aware of this before purchasing.
