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To change the data rate to DR0 you need to send one byte in binary representation 00010000 (0x10) to port 52. Many LNS interfaces have Base64 input and you can use an online converter from binary to Base64. 00010000 binary is “EA==” string in Base64.
To set 4 unconfirmed attempts on DR0 send “QA==” (01000000 in binary) to port 52
To change the data rate to DR3 you need to send “Ew==“ (00010011 in binary) to port 52.
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