Originally Posted by Mike Cross
If ATC can combine frequencies so that everything is heard on both why can't the mil?
RAF wouldn't pay for the upgrade.
I worked at a DERA unit where you could (and did) cross couple VHF and UHF so that both sides could hear all R/T. It was the same Comms fit as is standard in Military ATC units but with an extra software upgrade.
However, it is dubious whether this would have any benefit with the Military set up in ATC. The Zone / LARS position may be standalone, in which case that's all that particular Controller is working, or it might be combined with Approach. If the latter is the case you may only hear traffic departing (though some units have a separate departures frequency) or traffic initially calling for join. SOP then is if they are VFR they tend to stay with Approach, IFR they will then get handed to Director - so you won't hear them anyway.
The Civil system of 1 ATCO - 1 bit of airspace is totally different to the Military system which is based on 1 ATCO - 1 particular task.