The feature set

A full RTTY station,
rebuilt for Android.

Every part of the operating loop — copy, tune, transmit, log — in a fast Jetpack Compose UI, built on FT8AF's hardened radio stack. Here's what's inside.

20m · 14.074 MHzLive
050010001500200025003000
UTC 14:23:00Decoded in 64 ms● 14 signals
01 · Spectrum

Live band decoding & waterfall

Watch the whole 3 kHz passband at once. The waterfall scrolls continuously with UTC time markers and live mark/space tuning cursors, so you can see exactly where a signal sits and park on it instantly.

  • Continuous scroll with UTC time markers
  • Configurable spectrum width & zoom (Wide → 500 Hz)
  • Tap a signal to tune; TX marker stays aligned
Active QSO · EA8DHMacros
Send call
TX KD9XYZ EN52
Report sent
RX KD9XYZ EA8DH −12
3
Roger report
TX EA8DH KD9XYZ R−09
4
Confirm
5
Logged
02 · Operating

Programmable macros

One-tap function keys drive the whole exchange — CQ, answer, report, and 73 — with {VAR} substitution that fills in your call, the worked station, RST and exchange as the QSO runs. Tap the buffer, hit TX, and RTTYAF keys the rig and sends.

  • Macro keys: CQ → answer → report → 73 → log
  • {VAR} tokens for call, RST, grid and running serial
  • TX / STOP that keys and drops the rig cleanly
USB CAT + AudioConnected
RTTYAFAndroid
Your rigIC-7300 · FT-891
Mode
DATA-USB
BW
3000 Hz
PTT
CAT
03 · Hardware

USB CAT radio control

Plug your rig straight into your phone with a single USB-C cable. RTTYAF handles CAT frequency control, USB audio, and PTT — with a pile of reliability fixes for auto-connect races, multi-port handling, and serial control.

  • Rig model, control mode & audio device pickers
  • FT-891 correctly set to 3000 Hz in DATA-USB
  • TX volume mapped to the hardware volume buttons
Logbook · auto-uploadSynced
QRZ
DL7VEE JO62
Germany · 20m · RTTY
14:18
−18 / −09
Cloud
W3LPL FM19
Maryland · 20m · RTTY
14:02
−06 / −11
QRZ
JA3YBK PM74
Japan · 15m · RTTY
13:45
−12 / −15
04 · Logging

Cloudlog & QRZ auto-logging

Configure your log services once and forget them. The moment a QSO completes, RTTYAF pushes it straight to Cloudlog and QRZ — no exporting ADIF files, no copying callsigns by hand at the end of the night.

  • Cloudlog configuration dialog with automatic upload
  • QRZ automatic log upload
  • Every contact captured with both SNR reports
9:41

Waterfall

2.5 kHz·14 signals
Wide1.5 kHz500 Hz
01k2k3k
LISTENING·20m14.074
Decode Map Waterfall Log Setup
05 · Interface

Material 3 dark UI

The whole interface is a fresh Jetpack Compose rebuild on a Material 3 dark theme — high-contrast, legible at a glance in bright sun or a dark shack, and laid out for thumbs, with a compact density mode for tablets.

  • Jetpack Compose, Material 3, dark by default
  • Status-coded decodes: new, needed, worked, confirmed
  • Field-ready contrast and tap targets
Modem45.45 Bd
Baud
45.45 / 75
Shift
170 Hz
Mark
2125 Hz
Space
2295 Hz
USOS
On
Reverse
Off
06 · Modem

Tune it to the band

45.45 and 75 baud, the standard 170 Hz shift, adjustable mark and space tones, USOS (unshift-on-space), and a reverse toggle for inverted signals. Set it to match what you're hearing and pull weak copy out of the noise.

  • 45.45 & 75 baud, 170 Hz shift
  • Adjustable mark/space tones & reverse
  • USOS and an energy-gated squelch
And the unglamorous wins

Built on a
proven base.

RTTYAF inherits FT8AF's hardened USB CAT and audio stack, its Compose UI, and two full "bug bash" passes' worth of crash, leak, and lifecycle fixes — so the plumbing is solid before you key up.

Crash & leak fixes

NPE crashes, resource leaks, and threading races hunted down across the app.

Mark/space cursors

Live tuning lines on the waterfall show exactly where to park for solid copy.

Hardware TX volume

Set transmit level with the phone's physical volume buttons, mid-QSO.

Clean TX / STOP

One tap keys the rig and sends; STOP drops the carrier without a stuck tone.

Android 12+ clean

Lint errors and lifecycle bugs resolved for modern Android releases.

TX marker alignment

Transmit frequency cursor stays locked to your actual TX audio.

Ready to put a station
in your pocket?