Drofseh
commented
2 years ago Radios that should support this include the AN/PRC-77, AN/PRC-148, AN/PRC-152, and AN/PRC-117F.
Radios that should not support this include the AN/PRC-343 which has fixed channels.
I am not sure about the SEM series of radios and I do not have much experience using them.
In Acre2, if the omnidirectional setting is turned off, all radio antennas have realistic radiation patterns throughout their frequency range.
This means that depending on the use case some frequencies are much better for transmission/reception in that use case.
Examples:
See this video for the antena pattern for the AN/PRC-117F which is referenced in these examples: https://www.youtube.com/watch?v=a-ydqMUjAMY&list=PLBWDus4X4wWfAA4aM3U6J70XtwwStSUdz&index=6
If you want to assign a channel for Forward Air Control to allow communitcation with an aircraft, frequecies below ~130M Mhz have a pattern that is largely perpendicular to the direction of the antenna, as in the transmission is sent more strongly out horizontally across the ground and more weakly vertically into the air. Above ~130 Mhz the frequency pattern shifts higher and more parallel to the antenna, allowing for better communication with aircraft at higher altitudes.
This is also important in trying to balance TvT missions. If you look at that same video, you'll see at 30 Mhz there is a maximum total gain of about -15 dBi, while at 100 Mhz the maximum total gain is about 4 dBi, with a nearly identical pattern. This means if Side A is assigned a channel at 30 Mhz and Side B is assigned a channel at 100 Mhz, Side B will have a significant advantage in terms of transmission distance over Side A, giving them much better comms at longer ranges.
The AN/PRC-77 does not have channels at all, so being able to directly assign default frequencies is very important for this radio. See #433