I outlined the radio ranges of common German radio sets in German armored vehicles in this forum, a few yrs ago.
Basically, the radios had ranges of 8-11 kilometers in voice com mode, and say 15 - 30 kilometers in morse mode, both ranges depending on the transmitter model used in a given vehicle. In Command Ops, one grid box is 1 km wide/long. 8 grids (=8 km) is nothing, if the scenario covers large areas (say 30 km * 40 km).
Historically, tank units were pretty much on their own, once they lost radio (voice com) contact with the most forward friendly forces.
Morsed messages could be and were still transmitted, but in combat this mode couldn't be used, in most situations.
Some armored recon vehicles had retractable radio poles (height: 6-8 meters) and somewhat more powerful radio transmitters, but these were mostly used for artillery observation (often in or bordering to enemy territory, though).
So, recon or tank units tasked to scout or interdict enemy supply lines behind enemy lines, conducted their missions way outside their radio ranges (in Russia, both sides conducted such missions by pushing/filtering through enemy flanks, for example, sometimes with dashes of up to 20-35 kilometers), and raced back towards friendly lines to get back into radio range and to report results, sightings, locations of enemy supply lines/hubs, troop movements and/or worthy arty or bomber targets.
I am too lazy to dig out my old post, but I am sure that my post was pretty detailed.
If it comes to the creation of an East Front DLC, radio ranges will have to be rendered, imho, in order to accurately depict the historical (limited) capabilities for command and control in conjunctio with radio ranges. For instance, units outside the radio range (morse range) should not be able to call for arty, as a starter, imho.
There might be other ways/ideas to implement/emphasize the use/importance of radios and their particular ranges when it comes to recon missions or armored operations in general.
Maybe like this: If a fast unit finds/observes enemy units while being well out of morse radio range, then the enemy's EXACT location should only be presented to the player when the recon unit has reestablished radio contact. Not sure if something like this would be feasable.
The lack of information in the high echelon HQ about the whereabouts of say a Recon unit or a fast tank unit should make it into the game, somehow, imho.