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[Update 15 May 2021] ULARI Transceiver VHF 7W device was discontinued because the manufacturer of Linux-based boards for these devices (NanoPi Duo modules) stopped manufacturing them without any earlier notice. Please check out my ULARI Transceiver VHF 7W Duo2 for direct replacement with the same functionality.

ULARI Transceiver VHF 7W Hardware

ULARI Transceiver VHF 7W is based on NanoPi Duo 256 MB module from FriendlyARM. The device consists of a microprocessor module and a motherboard with all necessary external components including VHF transceiver, hybrid power amplifier, 7-pole low-pass filter. The whole system includes::

  • SMA VHF antenna connector,
  • A 100 Mbit Ethernet connector with surge protectors,
  • Two USB connectors with surge protectors, 5V/1A total current consumption (suitable for moderm LTE modems),
  • Wifi chip with external antenna,
  • RS-232 serial port (via 6-pin minidin connector),
  • DS18B20 thermometer connector,
  • Four leds informing about device operation,
  • SD CARD connector for operating system image.
This device is a standalone VHF tranceiver. All you need to do is to connect a proper VHF antenna and you can send and receive RF signals from VHF band.

Technical parameters

  • Dimensions (without connectors): 100x94x32mm,
  • Weight: 280g
  • Housing material: aluminium, PCB panels,
  • RX frequency: 136-174 MHz,
  • TX frequency: 136-174 MHz,
  • TX power: 3-7 W,
  • Low-pass filter: 7-pole,
  • VHF antenna connector: SMA female,
  • Wifi connector: SMA female (antenna included),
  • Power connector: round 5.5/2.1mm (with plus at center),
  • Thermometer connector: terminal with screws,
  • Serial port connector: minidin 6-pin female (1 serial port),
  • Supply voltage: 12-14 VDC,
  • Power consumption (at 12V): TO-BE-MEASURED

ULARI Radio Interface photos

ULARI Transceiver VHF 7W front view ULARI RTransceiver VHF 7W rear view ULARI Transceiver VHF 7W PCB view ULARI Transceiver VHF 7W NanoPi Duo module

NanoPi Duo pinout

NanoPi Duo pinout diagram with with description of used pins.

NanoPi Duo pinout diagram

Rear panel RS-232 port pinout

RS-232 port can be used to connect any serial port devices with RS-232 voltage levels. Devices with low current consumption can also be powered from this connector. GPS-RS232/Microsat/2 is compatible and works nice.

Minidin 6 pinout

  • Pin 1 – 5V output, do not short-circuit, max. current 100mA,
  • Pin 2 – GND,
  • Pin 3 – hard-wired to negative voltage for WS-2300/WS-2350 weather station support,
  • Pin 4 – RS-232 Port 2 TXD,
  • Pin 5 – RS-232 Port 2 RXD,
  • Pin 6 – not used.
hardware_vhf7w.txt · Last modified: 2021/05/16 00:57 by sq3plx