Expert Electronics extends their portfolio with a QRP SDR transceiver with 5W output power. The SunSDR2-QRP is a compact allmode transceiver which uses up-to-date digital components. A 16 bit analog digital converter (ADC) is clocked with 122.8 MHz sample rate and achieves a very good blocking dynamic range (BDR) of 115 dB. The excellent sensitivity and large signal handling capability is accomplished by using 9 analog bandpass filters in front of the ADC. The displayed spectrum width can be selected from 48 to 960 kHz. Up to a spectrum width of 384 kHz two simultaneous receivers are possible, above that only one. Additionally a 60 MHz panorama display is available.
In contrast to the already known SunSDR2-Pro transceiver the manufacturer has selected a smaller enclosure for the QRP transceiver, resulting in fewer antenna connetions. The audio output for headphones was maintained, just like on the larger radio. The audio signal for this output is created directly in the transceiver with an own 24 bit digital analog converter. The result is latency free high quality audio. Since the SunSDR2-QRP also offers a microphone connection right on the transceiver, there is no need to use the internal soundcard of the computer at all. Of course a headset conected to the computer can be used as well. One microphone connector (of two) on the radio is compatible with the Yaesu MH-31A8J microphone.
The connection to the computer is done via Ethernet cable. This is the better solution for high-end SDRs enyway, due to it's simplicity and higher speed than USB. A network infrastructure (Switch or Router) is not required, the transceiver can be linked with the supplied Ethernet cable directly to the computer. The morse key and a PTT is also directly connected to the radio, this simplifies set up very much. Additionally a 10 MHz reference clock input is available for very high precision frequency accuracy.
The SunSDR2-QRP transceiver can be easily remotely operated over a computer network by using the freely available ExpertRemote software. When a computer is available at the remote location (a Raspberry-Pi is sufficient), remote control over the internet is equally possible. For daily operation the supplied ExpertSDR2 software is used. This program offer rich functionality while maintaining a good ease of use. The QRP transceiver supports 8 open collector outputs which can be freely switched on and off, for example to switch antennas or a power amplifier.
All in all the SunSDR2-QRP offers an convincing price/performance ratio, regardless if you are looking for a compact portable transceiver or to start an affordable remote operated ham radio station.