MB-1 SDR Transceiver for shortwave and VHF/2m with built-in computer
With the MB-1 by Expert Electronics a very remarkable SDR transceiver enters the market. The MB-1 offers transmit and receive capabilities of the usual HF bands, plus 6m, plus 2m VHF. The outstanding feature is a built-in computer with 7" screen and a user interface like it is known from more traditional radios. The MB-1 combines excellent state-of-the-art technology with established design and usability principles.
Expert Electronics already has shown their proficiency with previous SDRs and uses the gained knowledge to further enhabce their products, also with the MB-1. The receiver is characterised by a very powerful 16 Bit AD converter with a large dynamic range of approx. 129 dB. The sampling rate is 160 MS/s, the HF signal is directly sampled with out an analogue mixer (direct down conversion, DDC). Various band and low pass filters are used to limit the signal right at the input stage.
The pre-installed software 'ExpertSDR2' offers two independent receivers, which can be tuned in a frequency range from 9 kHz to 65 MHz and between 96 and 148 MHz on VHF. The max. displayed panorama spectrum is 80 MHz wide, during normal operations the waterfall and spectrum can be set to max. 312 kHz width. The displayed range can be recorded at the same time for later playback, for example to check a QSO in detail, or for analysing an unknown signal.
The transmitter works totally independent of the receiver, the signal is completed synthesized digitally for a maximum of spectral purity. The hardware of the MB-1 supports full duplex operation, i.e. simultaneous receive and tarnsmit. This can be very useful when using a transverter or for satellite operations . The transmit power is 100 W on shortwave and 50 W on VHF/2m. The The transceiver has 4 separate antenna connectors for shortwave, and two connectors for VHF (N sockets). A built-in automatic antenna tuner is available as an option. Up to four keying outputs for PTT can be used for the timed control of PTT keying various accessories like amplifiers, antenna relays etc (sequencer function). Further other open collector signals are provided for control of switching signals by the radio.
Built into the MB-1 transceiver is an entire industry standard computer, using a Mini ITX board. Windows 10 is pre installed as operating system. The SDR software ExpertSDR2 is also installed and configured for immediate start of operation after unpacking the radio. The open concept of the integrated standard computer allows the user to install other software like for example a logging program, decoder software for digital modes and much more. Even the usual DX cluster can be monitored on the built in 7" screen, since the computer of course has a network interface for internet access. As storage medium a 128 GB large SSD is used. All in all the reult is a very compact solution, not only for the shack desk at home but also for portable operations. Of course external devices like a keyboard, mouse and monitor can be connected as well. The manufacturer has done a great effort in designing an enclosure for maximum shielding between computer and HF part of the MB-1. This prevents interference right from the start. Both components, computer and radio, are supplied by the same 12V power supply. If required the user can install an alternative operating system like Ubuntu Linux, the ExpertSDR2 software is available for this OS as well.
MB-1 Functions and Features
- Receive frequency range: 9 kHz – 65 MHz & 95 – 148 MHz
- Direct HF sampling receiver (DDC, Direct Down Conversion)
- Transmit frequency range: all ham radio bands from 160m to 10m, plus 6m, plus 2m VHF (cofigurable)
- Direct synthesising of the transmit signal (DUC, Direct Up Conversion)
- 100 W transmit power on HF, 50 W on VHF
- Receiver with 16Bit ADC @160MS/s
- Two independent receivers with up to 312 kHz waterfall and spectrum width each
- Up to 80 MHz wide panorama spectrum width
- Extremely short latencies, ideal for CW, direct audio output on the transceiverwith 24 Bit DAC
- Input for external 10 MHz hi-precision clock
- Optional built-in antenna tuner (HF)
- Connections for transverter and external filters
- 7 programmable control and sequencer outputs (open collector)
- ALC input for automated adjustment of transmit power when using an amplifier
- Full and half duplex operation
- Power supply, 100-240V AC input, 50/60Hz
- Built in computer with Mini-ITX Board (Intel Core i5 @3GHz, 8GB RAM, 128GB SSD, HDMI/DP, 4x USB3, 2x USB2, 1x GBit-LAN)
- 7" screen (1280 x 800 px resolution)
- Windows 10 installed ready to use
- ExpertSDR2 Software included in shipment, installed ready to use
- Extensible functions by any PC software (Decoder, Logger, Skimmer etc.)
 Full duplex operation is supported by the hardware, but not yet by the software. This function is planned for a future version of the ExpertSDR2 software.
 The transmit-enabled frequency range is depending on the setting of the ITU zone in the software.
70 MHz (4m): possible via the exciter output (0 dBm). Requires additional, external filter.
50 MHz (6m): depending on the selected ITU zone setting.
27 MHz (CB): depending on software setting.
5 MHz (60m): depending on software setting.
LW (137 kHz): possible via the exciter output (0 dBm). Requires additional, external filter.
MW (437 kHz): possible via the exciter output (0 dBm). Requires additional, external filter.