The 828 and the 863 in both the Mi-8 and the Mi-24 have frequencies preset in the Mission Editor per aircraft. In the Mi-8, the selector is above the pilot's right shoulder on the overhead console, with a choice of 20 presets and AM/FM choice. These can be edited from the defaults as you wish. The Mi-8 also has the option to manually tune the 863 to selected frequencies while in the aircraft, on the console between the Crew Chief's feet.
On the real dialler with the red cross, for the 863 with 20 x presets, the numbers go from 0 to 19. I have an authentic one of these in my pit, and it is a clockwork wonder! The same system applies to the 828 running from 0-9.
molevitch's post in R-828 Radio question was marked as the answer