Read the stations that never say a word

Most of what identifies itself on the air identifies itself in Morse.  A
repeater, a beacon, an unattended transmitter: four to six characters, over
in a second or two, and no speech anywhere in the capture.  Every one of
those was being thrown away, in three separate places.

The callsign book and the map were built inside the transcription branch,
on the reasoning that callsigns come out of transcripts.  They also come out
of Morse and out of APRS headers, neither of which involves a speech
recogniser -- so a receiver with none installed found none of them, and a CW
ident reached the sidecar and stopped there.  Both are now built whenever
classification is on, and all three sources go through one place.

The CW decoder only ran where the classifier had already said cw, ook or
carrier.  A two-second ident is a fraction of a capture named after whatever
filled the rest of it.  Every capture is offered to it now, once it has
finished; a decode does not relabel a capture that plainly holds speech.

And the decoder's own gates were written for a paragraph.  Three characters,
eight elements, and any repeated character refused -- which read VVV, DE, AR
and K correctly and then discarded them.  Short is the normal case now, on a
second bar: perfect timing, nothing undecoded, and the keyed tone at least
20 dB over its band.  That last is not decoration.  With four elements the
dot length is fitted to those very elements, so noise lands on the grid as
neatly as keying does; a third of a second of white noise decodes as a
perfectly timed V.  Over 200 noise blocks the loudest bin never rose 13 dB
above the median while keying at 3 dB SNR sits above 40.  One keyed element
is still refused: a single pulse is an E or a T whether a person sent it or
the squelch opened on a click.  288 non-Morse cases, no false positives.

Feeding that text to a callsign lookup made truncation matter.  A capture
opens when the squelch does, halfway through an element as often as not, and
half a character is not a smaller reading -- a K missing its first dash is
an A.  So the sliced character is dropped, and so is the rest of its word,
because what is left can read as a whole one: K1AA caught halfway through is
K1A, which is somebody else.  Across 1805 truncated captures that is 107
invented callsigns down to none, with 550 correct ones still found.

Phonetics, which is the other half of the ask.  A recogniser has never heard
of the alphabet -- it writes what the words sounded like:

  Whiskey-One-Alpha-Whiskey    hyphenated
  WhiskeyOneAlphaWhiskey       run together
  Whiskey1AlphaWhiskey         and half in digits
  wiskey one alfa whisky       spelled the way it sounded
  whiskey one alpha, uh, whiskey   with the hesitation written down

All read back to W1AW now.  A word is only taken apart when it is phonetic
all the way through, which is what keeps it off "kilometre" and "victorious".

Two bugs found on the way, both of which invented a callsign:

 - Nothing is joined across a slash any more.  The beacon W1AW/B came back
   as W1AWB, which belongs to nobody, and W1AW-4 came back as nothing at all.
 - Nor across a gap the sender chose.  A transcript's spacing is the
   recogniser's guess and may be closed up; a word gap in Morse is seven dot
   units, so "KU0W K" is a station signing off, not a longer callsign.

Also here:

 - saunterbrowse gives Morse a panel of its own, with the licence under it,
   searchable with / and readable with t.
 - --simulate no longer looks anything up or writes a map.  The demo band is
   invented but W1AW is the ARRL's own station, and it would have been
   pinned to the same map a real scan writes.
 - classify._psk_order took the logarithm of zero on a silent block.
 - The demo band has a repeater ident in it, and its Morse no longer runs
   one repeat into the next.
 - conftest refuses a real licence lookup from any test.

1161 tests, up from 1014.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016PsWPTweCT6pwxKngvVxcg

tests/conftest.py

@@ -1,6 +1,7 @@
 """Fixtures every test gets.
 
-Both of them are about not touching the machine the tests run on.
+All three are about not touching the machine the tests run on, or anyone
+else's.
 
 The cache: a lookup writes to ``~/.cache`` by default, and a test run that
 touches the real one leaves entries behind and reads back entries an earlier
@@ -10,10 +11,14 @@ The settings: locking a frequency out writes it into ``config.yaml``, and a
 test that reached the real one would silently change what the next real scan
 does.  The constant is replaced in every module that holds a copy, so that
 forgetting to pass a directory somewhere cannot end in someone's own settings.
+
+The network: a licence lookup goes to a public database and returns a real
+person's name and address.  No test has any business doing that.
 """
 import pytest
 
 import bandsaunter.browse
+import bandsaunter.callsign
 import bandsaunter.cli
 import bandsaunter.config
 import bandsaunter.tui
@@ -25,6 +30,21 @@ def isolated_cache(tmp_path_factory, monkeypatch):
                        str(tmp_path_factory.mktemp("cache")))
 
 
+@pytest.fixture(autouse=True)
+def no_licence_lookups(monkeypatch):
+    """No test may contact the licence database.
+
+    One did, silently, and passed -- it was only visible because the
+    assertion it failed printed a real operator's address.  A test that wants
+    answers stubs this itself; anything else fails loudly rather than going
+    to the network and being slow, flaky and rude about it.
+    """
+    def refuse(self, call):
+        raise AssertionError(f"a test tried to look up {call} for real")
+
+    monkeypatch.setattr(bandsaunter.callsign.CallsignBook, "_request", refuse)
+
+
 @pytest.fixture(autouse=True)
 def isolated_settings(tmp_path_factory, monkeypatch):
     where = tmp_path_factory.mktemp("config")