The Marker Beacon sound just comes abruptly on with constant volume, then is abruptly gone after passing over. In real life the Marker Beacon will fade in, reach max volume as you pass overhead, then fade back out. This would add so much to realism when flying.
In general you’re right, as it’s just an audio transmission over radio that will fade with distance from the (directional) antenna pattern. However, the output effect is going to depend on the audio panel as there is often an amount of squelching and muting before the marker beacon audio passes through to the speakers. For example, placing the GMA340 on high marker sensitivity will allow you to hear an OM farther away.
Marker beacons are highly directional, and that direction is up. The valid signal area is a 2,400 ft × 4,200 ft ellipse as measured 1,000 ft above the antenna. They don’t fade in and out.
That’s a bit extreme. They will fade a bit around the periphery of the pattern, but the point is you’re either going too fast through it to notice, and/or your IC system is gating it (muting it until it reaches a certain threshold).
Put your marker sensitivity on high and you will hear it from farther away and it will get stronger when you’re in the middle of the pattern.
Hmmm… I don’t think I’ve seen if MSFS will create this sound effect with the marker beacon sensitivity set to high. I will try that but doubt it will work.
And for the purists out there… and you know who you are, yes, the sound is brief as you pass over but I have not personally experienced it just suddenly blaring full volume and then gone after passing over. I do have enough real world IFR experience to back this up.
Yeah, the sim treats every radio signal as binary - either you’re getting it full blast, or not at all. It’d probably need to be a custom sound set for a specific aircraft. Or maybe a mod.
It does seem to add some crackle to radio signals if they are further away. Still intelligible, but not as clean as when you are closer.