The Australian company GenesisRadio is a producer of several kits for amateur radio. They are mainly single- and double-band SDR transceivery. The novelty is the SDR transceiver for bands 160m to 6m, G59 . The G59 motherboard can be expanded with additional blocks, e.g.. PA, ATUs or transverters on the VHF band. Currently, the first beta versions of this device are among radio amateurs.
Declared parameters of SDR G59
SDR receiver
– tuning step after 1Hz, IIP3 32-35dBm
– MDS: -116 up to -122dBm (TNC settings in UI-View for cooperation with AGW PE: -132 to -134dBm)
– RX sensitivity is 0.15 – 0.2uV pre 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 the signal level + 10dBm
– the receiver has a second input for the RX antenna
SDR transmitter
– basic power is 10mW, s 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 an electronic CW key with an 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.
It is said that making a kit requires more 100 hours. The construction process takes place in phases, in which components are placed in functional blocks, e.g.. power supply circuits, microprocessor circuits and so on. 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 seemed to be broken. Until the upgrade to the latest version of the Genesis software (modified PowerSDR by FlexRadio) meant a change and finally the first signals from the band sounded 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 a band segment, where the oscillator is tuned (more precisely, a 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 range 3500 – 3800kHz four frequencies must be entered into the synthesizer.
The segment can be displayed in the form of a spectroscope, waterfall etc. It is very convenient especially when watching VHF bands, where it is thus possible to immediately register off-frequency activity, which we are currently in the mood for. It is also possible to use a second receiver (the signal from the main RX goes to one earpiece, signal from the second RX to the second handset).
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. The compressor can also be switched on in TX mode, IF shift (manual displacement of the modulating signal relative to the filter, thus achieving 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 the mouse or keyboard. G59 shows the direction, which the development of devices will take. For the price, which is 349USD, it is possible to get a high-quality device.
