A consumer weather station is two things. The display on the kitchen wall is
one of them; the other is a plastic box on a fence post that says what it can
see every sixteen seconds, in the clear, to anyone who happens to be
listening. This reads the box.
A section of its own, like the aircraft one, and for the same reason: it does
not fit through the scanner. A sensor message is a burst of a carrier
switched on and off, a fifth of a second long, and the scan path is a squelch
and a recorder -- it would record the bursts as clicks in a WAV file and
decode nothing. `bandsaunter weather` listens, `bandsaunter readings` reads
a log back, `bandsaunter sensors` says what is out there. Item 6 in the main
menu is the same thing without a command line.
Five families: the Tower 592TXR, the 5-in-1, the 6045M lightning detector,
the 609TXC and the 606TX. Temperature, humidity, wind speed and direction,
rainfall, strike counts, how far off the storm is, and battery state from all
of them. Every one is implemented from its published description and checked
against frames built from the same description, which proves the framing, the
parity, the checksums and the arithmetic and is not the same as having held
one of each.
The naming is the point. A sensor broadcasts an identity, and that identity
is a number that came out of a hat in a factory; it tells one sensor from
another and is no use at all for telling which is which. So press n while
listening: the display comes down, the sensors are listed, you name one, and
it goes back up, with the receiver running throughout. That is the moment it
is possible -- the sensor is on the screen saying 3.1 degrees, and the person
watching is the one who knows that the cold one is the shed. An hour later it
is a list of hexadecimal again. Names are written the instant they are given
rather than at exit, to a neighbouring file renamed over the old one, and one
given before a sensor has ever been heard waits under its identity and moves
across when the first message says which model it is.
Four things keep the neighbours' doorbells off the display. The checks the
message carries; a second copy, for the two models that carry only one byte
of check between them; a plausibility range, because a checksum can be
satisfied by a message the hardware could not send; and where in the burst
the message sits. That last one is the one that is easy to miss: a seven-byte
message read out of the front of a real eight-byte one is made of that
message's own payload bytes, whose parity is already correct, so the parity
bits contribute nothing and one byte of sum is all that is left -- and
corroboration cannot help, the three copies being identical. What gives that
window away every time is that it ends a whole byte before the burst does.
The Atlas is nine bytes like the lightning detector and lays its payload out
differently, so every decoder insists on a message type it knows. Anything
else that frames correctly is reported with its identity and no weather,
because wrong weather under somebody's sensor name is a worse answer than
none.
ism.py now delegates to this rather than keeping a second implementation of
the tower sensor, which fixes the channel letters -- A is 3, B is 2, C is 0,
and there is no D -- and the battery bit, which is set while the battery is
good. The two thinly-checked models are not reported from a scan at all: a
scan hears one burst, and they need two.
The option menus are now handed the module that owns the options rather than
importing the aircraft one, so one set of screens drives both sections and
will drive a third.
169 new tests, checked against nineteen deliberately broken builds; two of the
tests were too weak to notice their own mutation and were rewritten. Full
suite 2252 passed. Built as 2026-09-07_01.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016PsWPTweCT6pwxKngvVxcg
An audit rather than a feature, prompted by wanting this fit to hand to
somebody else.
Five options had no command-line flag written down in the table the manual
is generated from -- location, hold, schedules, tile_url and speed_unit --
so five flags that exist were missing from the manual. Four of them did
exist under other names and are now recorded; hold had no flag at all and
has one.
Four switches could be turned off from the command line and not back on:
--no-lookup, --no-basemap, --no-airports and --no-labels had no positive
halves, so an option turned off in the saved settings could not be turned on
again for one run. All four now have both.
And adsb, which opens the window and draws a map when it stops, could not be
given any of the settings that decide what those look like: no --at, no
--radius, no --tiles, no --map-brightness, no --width, --fps, --trail,
--fade, --stale, --airports or --labels. It takes all of them now.
The manual had no list of the aircraft options at all -- the ADS-B sections
were hand-written prose -- so five of them appeared nowhere in it. It now
generates an AIRCRAFT OPTIONS section from the same table the menu and the
flags come from, and the readme carries a table of all thirty-four with
their flags and defaults. Three tests hold the three of them together: one
that every option records its flag, one that every flag the table claims
actually exists on a command, and one that the readme names them all.
The installing instructions now list every dependency rather than only the
optional ones: the four Python packages with their names in Debian, Fedora
and Arch, and librtlsdr, which is a C library and therefore the one thing
pip cannot bring and a virtual environment cannot supply. What reaches a
network is written down too -- which host, when, and which file it is cached
in -- since somebody installing this on a metered or air-gapped machine has
to be able to see that nothing is fetched behind their back. build-repo.sh
needs dpkg-dev and apt-utils, which a minimal system does not have, and now
says so.
Verified rather than asserted: a clean virtual environment, pip install from
this tree, and a real log read back through the installed command. It pulls
seven wheels rather than the four the page claimed, the other three being
what Rich brings with it.
Also: matplotlib is gone from the readme's dependency table, nothing having
imported it; ffmpeg and Qt are in it, both having been missing; ffmpeg is a
Suggests on the package; and resume.sh is ignored.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016PsWPTweCT6pwxKngvVxcg
A night's scan leaves hundreds of files, most worth nothing and a few of
them the reason it was left running. Sorting that out meant leaving the
browser and going at the directory with mv and rm.
Five keys, meant to be pressed once each going down the list:
S I N file it into saved/, investigate/ or noise/
u put the last one filed back
d delete it and its sidecars, for good -- asks first
m lock the frequency out, so no later scan stops on it
Each of these acts on the whole capture -- the .wav, the JSON sidecar, the
IQ, the transcript and the decoded data -- because a recording in one
directory and its transcript in another is a pair nothing will ever put
back together. A move that cannot be finished puts back whatever already
moved. The cursor stays on the row it was on, which is now the next
recording, since a cursor that jumped would make one-key-per-recording
impossible.
m writes to the lock-out list in the settings file, the same one the
scanner's own l key maintains, so a birdie found while reading last night's
recordings is gone from tonight's. It says "the next scan": one already
running read its settings when it started.
The subdirectories sit under the recordings directory, so a scan writing
there never looks in them, and saunterbrowse ~/bandsaunter/saved reads one
back.
Also here, because this is the first part of the browser that writes:
- The help screen is back inside eighty by twenty-four. It had grown past
the bottom of an ordinary window, which puts "q quit" off the screen.
- The footer drops keys in a deliberate order when the window is narrow,
rather than ellipsising whichever happened to be at the end.
- Moving or deleting what is playing stops the player first.
- The pty harness accepted an env and ignored it, so a test aimed at a
throwaway settings directory wrote to the real one. It honours it now,
and conftest redirects the settings directory for every test besides.
1014 tests.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016PsWPTweCT6pwxKngvVxcg
A long scan leaves hundreds of recordings, each with a JSON sidecar of
measurements and, where a recogniser heard speech, a transcript. Reading
that meant opening files one at a time and guessing which were worth
playing.
saunterbrowse is a second executable in the same package. Arrow keys move
through the recordings; the transcript of whichever is highlighted fills
the top of the screen, because that is the part anyone actually wants to
read. Enter plays it, handing the file to whichever player is installed
-- the recordings are ordinary WAVs, every desktop already has something
that plays them, and a browser that cannot start would be worse than one
that cannot play. t opens the whole transcript full screen when it is
longer than the panel, and says so rather than cutting the end off
silently. / filters on the frequency, the name, the identification, or
anything that was said, which is the point of it: "was the repeater
mentioned" is a question about content.
Sidecars are read only for the rows on screen, so a directory of ten
thousand recordings opens instantly. Where there is no transcript the
panel says which of the reasons applies -- Morse (decoded, and shown),
data, a bare carrier, or speech never offered to a recogniser -- because
those want different things done about them. It only ever reads.
Two things were only found by driving it through a real terminal.
sys.stdin.read(1) goes through a buffered text wrapper, which in cbreak
mode waits for more bytes than one keypress provides: the program drew its
first frame and then hung, while tests against a stand-in stream object
passed. It reads the file descriptor now, and the tests drive a pty. And
stopping playback signalled only the direct child, so a player that is a
wrapper script kept the sound going with nothing on screen to stop it; the
whole process group is signalled instead, which is what start_new_session
was there for.
man saunterbrowse ships beside man bandsaunter, and the two point at each
other.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016PsWPTweCT6pwxKngvVxcg
Every setting now carries a paragraph saying what it is in everyday terms
and why someone who does not already speak radio would turn it up, down,
on or off: what the squelch knob actually is, why automatic gain is a bad
idea for scanning, why a bias tee can damage equipment, why setting the
transcription language matters on noisy audio. The menus and
`config --describe` show it alongside the existing technical detail.
packaging/make-man.py generates bandsaunter(1) from that same table, so the
manual cannot document a setting the program lacks or miss one it has --
tests check both, that the page renders through groff without a single
warning, and that the guidance survives into the rendered output. Around
it are hand-written sections on the commands, entering frequencies, the
band plan, lock-outs, the keys during a scan, HF, single sideband, files,
environment variables and worked examples.
The .deb regenerates and installs it rather than shipping a copy, so an
installed manual always matches the installed program.
The README picks up what the last few commits added: the plain display as
a saved setting, what the settings tests now guarantee, and where to read
the manual before installing.
Version is the day's build: 2026-08-22_01.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
The Dust Council