github.com/strickyak/svxlink-raw-audio-udp-receiver

svxlink-raw-audio-udp-receiver

lms.go: A calibration program for Rx volume in svxlink.

Print 28 plus the Log-Mean-Square of groups of 50 samples, and then ":" and the max of every group of 10 of those. Listens on UDP for the packet format that comes out of svxlink when you specify RAW_AUDIO_UDP_DEST=127.0.0.1:1825 in your [Rx1] clause. The samples are between -1 and 1, so their squares are between 0 and 1. The printed 28+LMS with my IC-2730 radio with volume at 1:30 and "Mic" device at 42% volume tend to be

• 7 to 8 when radio squelch is closed,
• 15 to 18 when radio squelch opens but has dead air (receiving empty carrier),
• 19 to 23 when I am speaking,
• 20 to 24.5 for the repeater voice ID,
• 22.7 to 23.2 for the bee-boop,
• 25 is just about the maximum,
• 25.77 on the carrier drop.

Hint: less -p ': 2' test-and-id-and-drop.42.130.lms with 2 spaces between : and 2 to find non-dead air.