The Field Notebook is a 14-part operator’s tutorial that reads the GopherTrunk debug.log one line family at a time. The Cookbook told you which lines prove a rig is alive; From Spec to Shipping argued that the log is an instrument, not a diary. This series is the instrument’s manual: for each line — startup WARNs, lock and hunt lines, the TETRA and DMR decode-status counters, the carrier-offset WARN, the DMO noise meter versus its traffic counter, overruns and host_drops, the MRC health line, capture and recorder lines, the voice chain’s teardown reasons — it answers the same three questions. What does each field measure? What does a healthy rig print? Which deep dive do you open when it doesn’t?

The running thread is that almost every field report in the issue tracker already contained its own diagnosis in a line nobody read: a counter that was a noise meter mistaken for traffic, a success-only line that carried no information, a WARN firing on one sample of a ten-second condition. The series ends with the one-page field card and with how to turn a log into a bug report that gets fixed — what to paste, which capture to make, and what “verified” means before anyone closes the issue.

Every post reads three ways: a TL;DR + cheat-sheet for skimmers, bold headers, tables, and diagrams for the medium read, and full prose with real log excerpts for the deep read.

New here? Start with When decoding fails in the Scanning module for the big picture, then come back for the lines.<ol class="post-list series-list"><li class="post-card"> <h2 class="post-card__title">The Field Notebook, Part 1: Startup — The Lines Before the First Lock</h2> <p class="post-card__meta"> Tutorials </p><p class="post-card__desc">An operator’s reading of GopherTrunk’s startup log block — the two “gophertrunk starting” lines, device opened and gain set, and the config WARNs the daemon prints before its first lock, including the gain-in-tenths trap, two systems on one control tuner, and the pool gate that used to log nothing.</p></li><li class="post-card"> <h2 class="post-card__title">The Field Notebook, Part 2: Lock Lines — Locked, Lost & Transitions</h2> <p class="post-card__meta"> Tutorials </p><p class="post-card__desc">An operator’s reading of GopherTrunk’s control-channel lock family — cc-hunt trying and locked, the per-protocol cc locked lines, the cc.lost events behind a re-hunt, cchunt hunt failed with its IQ diagnosis, the camped idle state, and the transition counter that turns “it drops sometimes” into a number.</p></li><li class="post-card"> <h2 class="post-card__title">The Field Notebook, Part 3: The TETRA Decode-Status Line</h2> <p class="post-card__meta"> Tutorials </p><p class="post-card__desc">An operator’s field-by-field reading of GopherTrunk’s tetra decode status line — sb_bursts, bsch_ok and bsch_fail, sch_pdus and sch_pdus_fail, frag_abandons — the “locked but deaf” signature where bsch_ok climbs while sch_pdus stays zero, and the signal-time resync and payload-drought watchdogs that recover it.</p></li></ol><p class="blog-feed-link"> See all tutorials or subscribe via RSS. </p>