@sputman101 I had this issue with a few planes in the past and did some work to dig in to why some planes work and some don't.
Long story short: SOME developers put in an automatic .5 seek. The Just Flight Pipers have this for example...
You set 342 because you physically can't put in a ".5" and it will tune to 342.0 see if the signal is detected, then automatically and silently it'll tune 341.5 and take a second or 2 to see if it gets a signal. If it does it'll lock to that. If not, it'll go back to 342.0 and cycle between them until it gets a signal lock.
You can see it happening if you have a way of motioning simvars: (A:ADF ACTIVE FREQUENCY:1, Number) will show it. You'll see it cycling between .0 and .5, then back to .0 and so on, even though the instrument itself can't show decimals.
Just to note that, as Nick says, the Black Square fleet doesn't work like that
But hopefully it'll give you some insight into why SOME planes that show just integer values, still seem to work.
And like you say, in real life the tuning is so broad you could put in .5 or .0 and it would just work. Doesn't work like that in sim though, unless the devs put in that .5 seek cycle, or give a switch like Nick.
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