Tech Minds YouTube review questions #2
Questions from the Tech Minds YouTube review:
What is the gps antenna for?
A number of things actually. There is a software-defined GPS receiver as part of the Kiwi. it is used to provide automatic frequency calibration of the main 66.67 MHz low phase-noise oscillator that feeds the ADC and FPGA. It's also used to generate GPS timestamps that are applied to the audio stream to support the Kiwi's TDoA direction finding capability. GPS time and date will be used if it cannot be sourced from the Internet. Determining timezone requires determining location and GPS obviously helps with that. Otherwise approximate location from the public IP address must be used.
The KiwiSDR map is currently one of the very best things on the internet IMO.
This is due to the efforts of our friend Pierre who runs the numbers station site priyom.org. You'll note that map.kiwisdr.com forwards to his map site rx.linkfanel.net. Pierre has provided the Kiwi map service for many, many years and we are indebted to his contribution.
Can this receiver record a section of the RF spectrum to an IQ file similar to the RSP family of SDRs?
Currently only the bandwidth of the audio channel which is either 12 or 20.25 kHz depending on the mode the Kiwi is set for. There is a utility written in Python for connecting to the Kiwi and recording audio, waterfall and S-meter data including as IQ files. See: kiwiclient. There have been some experiments in providing a wide band mode so that several hundred kHz of spectrum could be recorded or processed, but this has not yet been released. See: wideband-iq-streaming-mode-for-local-processing
