User manual for the Shangzhi SM34-32ch-433MHz wireless serial communication module, covering features, specifications, wiring and operation.
The SM34-32ch-433MHz module provides up to 32 configurable channels in the 413‑443 MHz ISM band with a transmit power of +30 dBm (1000 mW). It supports TTL‑level UART or RS‑232 interfaces, multiple baud rates, and includes error‑correction and watchdog functions for reliable half‑duplex communication.
The manual describes power requirements (+3‑5.5 V, <5 µA standby), pin definitions, channel selection via JP2 jumpers, antenna recommendations (50 Ω), and installation steps. Technical specifications, dimensions (47 mm × 30 mm × 7 mm), and accessory lists are also provided. This manual is written in Chinese.
| Transmit Power | +30 dBm (1000 mW) |
|---|---|
| Frequency Range | 413‑443 MHz |
| Number of Channels | 32 |
| Supply Voltage | +3‑5.5 V DC |
| Receive Current | ≤27 mA |
| Transmit Current | ≤495 mA |
| Standby Current | ≤5 µA |
| Operating Temperature | -20 °C ~ 85 °C |
| Dimensions | 47 mm × 30 mm × 7 mm |
The module can reliably transmit over 2500 m when the antenna height is greater than 1.5 m.
The SM34 provides 32 selectable channels.
It offers a TTL‑level UART interface (COM1) and an RS‑232 interface (COM2), but only one can be used at a time.
A 50 Ω impedance antenna is required; the manufacturer can supply matching antennas on request.