The Australian company GenesisRadio is the producer of several kits for radio amateurs. They are mainly single- and double-band SDR transceivers. The novelty is the SDR transceiver for bands 160m to 6m, G59 . The G59 motherboard can be expanded with other blocks, e.g. PA, ATU or transverters on VHF bands. Currently, the first beta versions of this device are among radio amateurs.
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Declared parameters of SDR G59
SDR receiver
– tuning step after 1Hz, IIP3 32-35dBm – MDS: -116 to -122dBm (with preamplifier: -132 to -134dBm) – RX sensitivity is 0.15 – 0.2uV for 10 dB S/N – Suppression of unwanted mirror frequency -35dBc to -50dBc (hardware) or -60dBc (hardware + software) SFDR (Spurious free dynamic range) is 93-100dB to over 100dB for the G59C model – 1dB compression is at +10dBm signal level – the receiver has a second input for the RX antenna
SDR transmitter
– basic power is 10mW, with GPA10 10W – carrier frequency suppression 45-60dBc (hardware) – suppression of unwanted TX mirror signal: -35dBc to -50dBc (hardware) or more than 60dB (software) – built-in microphone preamplifier and electronic CW key with earpiece Thanks to Oliver MW0JRX, I have the opportunity to familiarize myself with the basic G59 module without an amplifier (power 10mw). Most of the components on the printed circuit board are in the classic design with terminals, only about thirty are in SMD design. All connectors are also on the PCB. The circuit solution also ensures the switching of RX/TX I and Q signals from/to the sound card.
The kit is said to take over 100 hours to make. The construction process takes place in phases, during which components are installed in functional blocks, e.g. power supply circuits, microprocessor circuits, etc. Wiring is definitely not suitable for a beginner, even though the construction instructions are very precise and detailed.
Although I received the G59 SDR transceiver already assembled and tested, the first attempts were not successful and the module appeared to be broken. Only the upgrade to the latest version of the Genesis software (modified PowerSDR by FlexRadio) meant a change and the first signals from the band were finally heard in the headphones.
You have to get used to the controls or use as much memory as possible. Depending on the bandwidth of the sound card, it is possible to work in the band segment where the oscillator is tuned (more precisely, the synthesizer Si570). The segment has a width according to the capabilities of the sound card, in my case 96kHz. For example, to fully cover the 3500-3800kHz range, four frequencies must be entered into the synthesizer.
The segment can be displayed in the form of a spectroscope, waterfall, etc. It is very advantageous especially when monitoring VHF bands, where it is thus possible to immediately register activity outside the frequency to which we are currently tuned. It is also possible to use the second receiver (the signal from the main RX goes to one earpiece, the signal from the second RX to the second earpiece).
The software provides great freedom in choosing a filter or improving the signal. A separate RX and TX equalizer is also a matter of course. In TX mode, it is also possible to turn on the compressor, IF shift (manual shift of the modulating signal relative to the filter, which achieves a different timbre of the voice), VOX,...
Here are some recordings with the SDR G59 from the bands
The reception is very good and I dare say that in some situations the G59 SDR outperforms many classic devices. The disadvantage of these devices is relatively complicated control, because all operations must be done with a mouse or keyboard. The G59 shows the direction in which the development of devices will go. For the price which is 349USD, it is possible to get a high quality device.
