Paul, N1BUG, announced on the evening of 4th December 2018 that he would be transmitting DFCW60 on 137.779 kHz overnight. This provided an opportunity to experiment with the Argo software by I2PHD.
The KiwiSDR was tuned to 136.000 kHz and the audio fed to Argo via a virtual audio cable. The Argo spectrum was centred around 1779 Hz. The grabber is accessible, when active, via the following link. Screenshots from last night below: