Reported with two screenshots: both slices in USB on an inverting transponder,
slice B sitting at exactly 435.100000, and the red TX badge on the 2 m DOWNLINK.
The log named the cause in one line:
flex: satellite armed (rx slice 0, tx slice -1)
Creating a slice is asynchronous — "slice create" is answered later with the
index — and SetSatellite returned without waiting. Everything downstream then
ran against an uplink of -1 and silently did nothing: no antenna, no CTCSS tone,
no sideband, never tuned, and never sent "tx=1". So the radio went on
transmitting on the downlink, which is the one failure here that puts a signal
where it must not go, and the frequency and mode on screen were simply the ones
the slice had been created with.
Three fixes, because the ordering can fail in more than one way:
- Arming waits for both indices before reporting the pair armed, and says so
plainly when the radio does not produce them.
- The uplink is adopted from the SLICE STATUS as well as from the create
reply. The status needs no sequence-number correlation: if satellite mode is
armed, the uplink is unknown, and a slice is in use that is not the
downlink, that is it — the radio is saying so.
- What the uplink is owed is remembered — its mode, its antenna, its tone —
and given to it when it appears. Those three are sent ONCE; only the
frequency is re-sent every tick, so a slice that arrived late kept nothing.
Co-Authored-By: Claude Opus 5 (1M context) <[email protected]>
Three things the tracker was leaving to chance on a FlexRadio, all reported from
a real pass.
ANTENNAS. Settings ▸ FlexRadio holds a per-band RX/TX antenna map, and it was
applied in exactly one place: the entry form, on a band change, to the active
slice. A pass never goes through that path — the tracker arms two slices itself.
So both were left on whatever the radio last used, and a station with
transverters (XVTA on 2 m, XVTB on 70 cm) heard nothing at all, having
configured precisely the thing being ignored. The two slices are on two
different bands, so they cannot share one setting: the downlink takes the
receive antenna for ITS band, the uplink the transmit antenna for its. Per
slice, not through sendSlice, which addresses whichever slice is active — during
a pass that is the downlink, so the uplink would never have been set.
SIDEBAND. satMode forced USB above 30 MHz on both sides. An inverting
transponder turns the passband over, so lower sideband up comes back as upper
sideband down: FO-29, RS-44 and AO-73 were being worked with the operator's own
audio going through upside down. The tracker now decides both sidebands from the
transponder's inverting flag and passes them separately; a bare "SSB" still
means USB, so nothing else changes.
CTCSS. Nothing set it, on any bird. The frequency plan has carried the tone all
along — 67.0 on SO-50 and AO-91, 141.3 on PO-101 — and an FM repeater does not
answer without it, which is indistinguishable from a satellite that is not
there. It goes on the uplink slice, value before mode so the radio cannot
transmit the previous tone in the gap between two commands.
Written against the SmartSDR slice API and UNTESTED on hardware.
Co-Authored-By: Claude Opus 5 (1M context) <[email protected]>
The hard part of satellite tuning is not the arithmetic, it is deciding
who owns the dial. A tracker that forces both frequencies fights the
operator every time they turn the knob to follow a station across a
linear transponder; one that never touches the receiver leaves them
chasing a signal that slides nine kilohertz across a 70 cm pass.
So the operator owns the receiver and the tracker follows them. Every
second it asks the radio where the receiver actually is. Where it put it,
nothing has changed. Further than a dial-turn's tolerance, and the
operator has chosen a station: what they landed on is converted back into
a nominal frequency, and the transmitter is derived from that. Which is
the division of labour on a linear bird — the operator listens, the radio
does the sums.
Three ways to reach the radio, because a satellite pair is a shape of
operating rather than a manufacturer's feature. An IC-9700 or IC-9100 is
asked for its OWN satellite mode: it pairs main and sub, gives full
duplex, and keeps the dials linked the way its designers meant, which is
always better than an imitation built out of split. A Flex gets two
slices, A the downlink and B the uplink, created when missing, because
"slice B does not exist" is not something to make an operator fix at the
start of a ten-minute pass. Everything else gets the downlink, and is
told so — half the job announced beats half the job hidden.
What goes in the log is the NOMINAL pair. Two stations working each other
through a transponder read different numbers off their dials at the same
instant; the only figure they can both agree on is the transponder's own.
FREQ is the uplink and FREQ_RX the downlink — the one place a satellite
QSO differs from every other kind, and the reason FREQ alone cannot
describe one.
rouggyandClaude Opus 5