Тур 2

The main secret in such measurements is preliminary calibration. You need to determine in advance the values of signal delay to your QTH and the Doppler shift for the current contest time. Knowing these corrections, you need to use them. They will be different for each location.

Audio from Edlad FMD Duo fed to PC and oscilloscope. Frequency offset measured on Spectrum Lab. Peak_f readings written to a file every few seconds and post processed. Pulse width and UTC offset measured on oscilloscope triggered at 1pps from the RFzero. Screen grabs taken from the oscilloscope for later analysis. Latency through the Elad measured by generating local RF pulses from a Siglent SGS1062X generator which is locked to the RFZero 10MHz reference.

Recorded SSB audio, switching in GPSDO +500 Hz for reference. Tuning to CHU Canada for PPS. Signal deep in the noise and recognizable. only briefly over 15 minutes. Using SCILAB tools for bandpass filtering - but extreme multipath fading present. Much of this is a guess.

Cheap rf-generator 1 kHz below, measured. Audio compared to another generator at 1 kHz with oscilloscope in XY mode. Time measured with cursor on scope.

Calibrate IC-705 frequency via RWM time signal transceiver. Homebrew Software to pull audio from rig and write timestamps for audio parcels as they come in. Precision of timestamps relies only on NTP. A lot of Jupyter Notebook magic to do the actual measurment.

Used webSDRs to record WAV files. Analyzed WAV file data using Scilab scripts and cellphone audio spectrum analyzer.