SimpleSSTV

Encode and decode SSTV signals

Free · In‑App Purchases

Transmit and receive SSTV images for free! With automatic listening, recording and post-processing features. SimpleSSTV is a native iOS app for encoding, decoding, and live-transmitting slow-scan television (SSTV) signals — the method ham radio operators use to share images over audio frequencies. Slow-scan television converts images to audio tones. Each pixel's brightness becomes a specific frequency between 1500-2300 Hz. Sync pulses at 1200 Hz mark line boundaries. The result is an audio signal you can transmit over any voice-capable radio, or record for later playback. SSTV has been used by amateur radio operators since the 1950s. It's still actively used today on HF bands, VHF repeaters, and for receiving images from the International Space Station. ENCODING (Image → Audio) • Load any image from your photo library, camera, or Files • Automatic resize and crop to SSTV resolution • 14 supported modes covering all major SSTV formats • Real-time encoding with progress visualization • Play audio directly through speakers for VOX-triggered transmission • Export to WAV or M4A for later use • Optional FSK ID and CW ID (Morse code) callsign transmission • Test pattern generator for signal testing DECODING (Audio → Image) • Load WAV, M4A, or MP3 audio files containing SSTV signals • Live microphone capture for real-time SSTV reception • Automatic mode detection via VIS code identification • Precision audio trimming with dual-view waveform editor • Re-decode saved images with different mode, sync offset, or slant correction • Handles real-world signal imperfections: timing drift, noise, sample rate variations • Optional decode watermark stamps mode, timestamp, and callsign on received images • Waterfall spectrogram display shows signal frequency over time Note: It's super important to get a clean audio signal into the decoder. There's a new help section in settings with audio setup advice, USB adapter recommendations, and decode troubleshooting. LIVE CAMERA MODE • Real-time camera feed with front/back camera switching • Three trigger modes: Continuous, Motion-triggered, or Periodic interval SUPPORTED MODES (14 total) • Martin M1 (114s), Martin M2 (58s) • Scottie S1 (110s), Scottie S2 (71s), Scottie DX (269s) • Robot 36 (36s), Robot 72 (72s • PD50, PD90, PD120, PD160, PD180, PD240, PD290 AI CARD GENERATOR • Generate custom QSL calling cards with AI-powered image generation • 8 built-in styles or write your own prompt • Callsign and greeting rendered directly on the card • Tap any recent card to reload it with all original settings ISS SSTV EVENTS • Get notified when the International Space Station transmits SSTV images • Automatic alerts before and during events, with frequency, mode, and callsign info • Info card on the decode tab with event details and countdown FAQ & SETUP TIPS • Practical advice on audio setup and USB adapters • Decode quality troubleshooting • Quick reference for all 14 SSTV modes IMAGE LIBRARY • Automatic saving of encoded and decoded images • Grid view with full preview, metadata, and sharing • Re-decode any saved image with different settings • Filter by encoded or decoded 10 LANGUAGES Available in Arabic, Chinese (Simplified), Dutch, English, French, German, Polish, Portuguese (BR), Spanish, and Turkish — with full right-to-left support. PRIVACY No accounts, no analytics, no tracking. Your images and audio stay on your device. Buy once, use forever. We do not use, sell or share your data for advertising or marketing purposes. Note however that if you use the optional QSL card generator, your prompts will be sent to Google's servers for image generation. Be aware: Encoded images are audio signals — anyone receiving the audio can decode them! REQUIREMENTS • iOS 18 or later • Camera access for live mode • Microphone access for live decode This simple, no nonsense utility was built by a ham radio operator for ham radio operators. 73!

Ratings & Reviews

  • This app’s overall rating was recently reset.

Added ISS "notice" event type, to show ISS information that isn't an SSTV event such as news about radio outages, etc.

Version 0.9.2

The developer, Jeroen Rombouts, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .

  • Data Not Collected

    The developer does not collect any data from this app.

    Privacy practices may vary, for example, based on the features you use or your age. Learn More

    Accessibility

    The developer has not yet indicated which accessibility features this app supports. Learn More

    Information

    Seller
    • Jeroen Rombouts
    Size
    • 4.6 MB
    Category
    • Utilities
    Compatibility
    Requires iOS 18.0 or later.
    • iPhone
      Requires iOS 18.0 or later.
    • iPad
      Requires iPadOS 18.0 or later.
    • Mac
      Requires macOS 15.0 or later.
    • Apple Vision
      Requires visionOS 2.0 or later.
    Languages
    English and 9 more
    • English, Arabic, Dutch, French, German, Polish, Portuguese, Simplified Chinese, Spanish, Turkish
    Age Rating
    4+
    In-App Purchases
    Yes
    • Remove or change encoder watermark $2.99
    • 120 AI Card Credits $8.99
    • 30 AI Card Credits $3.99
    • 10 AI Card Credits $1.99
    • Learn More
    Copyright
    • © Strange Loop Software
  • Privacy Policy

    • Supports

    • Family Sharing

      Some in-app purchases and subscriptions may be shareable with your family group when Family Sharing is enabled. Learn More

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