[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),
ULARI Radio Interface photos
NanoPi Duo pinout
NanoPi Duo pinout diagram with with description of used pins.
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.
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.