A basic one will make noise when you trigger it with your radio via an open channel. This is great when you are trying to locate your model in heavy brush, or just thick grass.
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I'm one of a group of beta testers that has been using this product for more
than two years. It's been on numerous combat planes
that eventually all go out of control and end up in the bushes or over the trees.
In those two years we have never lost a plane with one of these in it.
The low voltage warning is unconfigurable. "The threshold is set at 4.4v for a 4.8v pack or 5.5v for packs of 6v or higher." How would it even know what size "pack" I am using? It constantly goes off because the APM is only sending 4.25v to my reciever. Also, a few of the tones are pretty loud, but not all. (Note from Aloft: Even if one of the lower level sounds is selected, if the model alarm is activated for more than 2 minutes it will change back to its loudest sound to help locate it.)
I have this setup on my VAS banshee. It has already saved me a couple long walks as i totally miscalculated where i had crashed. I fly it FPV and what it looks like in the sky verses the ground is totally different. This is loud enough to hear from far away. I have it setup on its own channel on my taranis. Failsafe turns this on and i can flip it on whenever i want manually.