Features & Capabilities

Simple Morse Decoder App for CW Beginner It is a Morse practice App that you can use to check if you are keying the correct code.

This is an App that decodes Morse code input from the microphone. It is a Morse practice App that you can use to check if you are keying the correct code. Signals with good S/N can be decoded correctly, but signals with bad S/N cannot be decoded correctly. Also, the performance will be degraded for extremely slow or fast signals. Usually about 5 to 10 characters are required for speed synchronization of Morse Code. Adjust the input signal so that the peak value changes from level 6 to level 7. Make fine adjustments to each parameter according to the reception status.

[Additional Functions] -In addition to the decoder using BPF, a new decoder using FFT has been added so that it can be switched according to the usage. -AFD (Auto Frequency Detector) function has been added to the decoder using BPF, and BPF can be set automatically by pressing the AFD button. -The decoder using FFT automatically follows the strongest signal in the band by AFD (Auto Frequency Detector) and AGC (Auto Gain Control). You can also hold the AFD / AGC parameters by pressing the Lock button.

  • There will be a time lag of about 1 to 2 seconds for AFD tracking.

[Control parameters]

  1. Audio Input Level 2.BPF ON/OFF 3.BPF of Center Frequency 4.BPF of Band Width 5.CW Speed Control ON/OFF 6.CW Speed Control Low, Mid1, Mid2 or High 7.Delete All Decoded Text 8.Realtime CW Signal Display 9.Input signal recording / playback function *Japanese/KANA text is not supported.

[Note] Since the signal after BPF is output to the audio output, it can also be used as an AF-CW filter.

[URL of this App working example video] https://youtu.be/Pwp7W4m-m34

User Growth & Download Statistics

App
By:
koji kamogawa
Rating:
5.00
(6)
Version:
3.3.0 Last updated: 2026-01-23
Version code:
881748205
Creation date:
2020-06-21
Compatible devices:
Size:
5.38MB
URLs:
Website ,Privacy policy
Full description:
See detailed description
Source:
Apple Apps Store
Data ingested on:
2026-06-05
Compare stats and ranking:

Contact the developer

Chrome-Stats does not own this Apple app. Please use these information below to contact the Apple app developer.
Developed by:
koji kamogawa
Apple Apps Store
https://apps.apple.com/us/app/rst-decoder/id1519587362
Website:
https://admob-app-ads-90661.web.app

User Reviews

After a few minutes to see what it’s all about, it showed the noise and code clearly. A bit of fiddling and I was copying nice code, as well as some pricy software. Of course, signal fading and bursts of occasional QRM would lose the code as most others also do. I will work more with this one, and so far I am very satisfied!
by Ea*****, 2023-01-17

If you think that this will copy someone with a bad fist, you’re an idiot. It does well with a strong signal and a good fist, as it should. The two decoding algorithms, Work well, even with QRN. If you don’t like what it does, then decode by ear, but go get a hearing aid, because you can’t hear like you did when you were in your 20s.
by ri*****, 2022-06-22

Works great for practicing and making sure I’m keying right, one thing I would like to see in this app is the ability to have the app in landscape.
by Ne*****, 2021-10-22
View all user reviews ›

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