Surecom SR-112 repeater. Fake? (see description)
The device listens for only 3-4 seconds, then, on its own, it goes into transmission mode. If, at this moment, I have not finished the transmission, I do not hear any response.
Purchased here - https://clck.ru/WghU3
I asked for technical support - in 2 places, on the manufacturer's website and in, as I understand it, the official store (email in the comments) - they advised to increase the volume on the radio connected to the repeater. I tried it - it seems - it works.