Why do you think something is wrong? What value are you expecting?
The value in raw: 'BQH/AQAA' is Base64 encoded and tells you that you sent the binary data 0x0501FF010000.
That could be two numbers sent with 3 bytes each, LSB, in which case you could use the example for decoding coordinates to get the original values back (which would then be -65275 and 1). But only you know what data your node is sending, and how it encodes it.