The radio in this video is a Kenwood TH-D74A HT. I used a roll-up antenna temporarily affixed to a 7ft fiberglass pole.

Slow Scan television (SSTV) is a picture transmission method used mainly by amateur radio operators, to transmit and receive static pictures via radio in monochrome or color.
The SSTV transmissions for this event are scheduled for April 11 - 14, as part of the Celebration of the Cosmonautics Day, which falls on April 12. Images will be related to the Interkosmos project (https://en.wikipedia.org/wiki/Interkosmos).
This opportunity should cover most of the world during the operational period.The image transmissions should be on 145.800 MHz and the mode is planned to be PD120.