# RST Scope — Spectrum&WaterFall Display App

> Amateur radio spectrum scope and waterfall display app with audio input analysis. (iPhone/iPad app by koji kamogawa.)

- Source: https://appshunter.io/ios/app/rst-scope/id1550582276 (this page in markdown: same URL + `.md`)
- Developer: [koji kamogawa](https://appshunter.io/developer/1488210713)
- Category: Utilities, Education
- Price: Free
- Rating: 5.00/5 from 1 App Store ratings
- Age rating: 4+
- Requires: iOS 15.6 · 5 MB
- Languages: American English, Japanese
- Released: 2021-01-28
- Data updated: 2026-08-22
- Monetization: ad-supported
- User reviews in markdown: https://appshunter.io/ios/app/rst-scope/id1550582276/reviews.md

## What is RST Scope?

This is an app for amateur radio operators with a narrow band of audio frequency, spectrum scope & waterfall display.

You can get a rich display by microphone inputting the speaker output of a radio that does not have a spectrum scope or waterfall function. The FFT allows you to distinguish between the dot and dash of Morse code.

[function]
1. Ability to change the speed of the waterfall
2. Ability to adjust the level of audio input
3. Function to switch the display band between wide and narrow
4. Display pause function (pause / cancel by touching the screen)
5. Function to switch the cross hatch ON / OFF by longTap
6. Frequency resolution is fixed at 40Hz.
7. Function to switch the USB/LSB by Left/Right Swipe
8.Recording/Playback function of Input Sound

RST Scope(Free) 
https://www.youtube.com/watch?v=1s9RvOFp52g

## Key features

- Spectrum scope and waterfall display
- Morse code distinction via FFT
- Adjustable waterfall speed
- Adjustable audio input level
- Switchable display band (wide/narrow)
- Display pause function
- Recording and playback of input sound


## Frequently asked questions about RST Scope

### What is RST Scope used for?

RST Scope provides a spectrum scope and waterfall display for amateur radio operators. It helps visualize audio frequencies and distinguish Morse code signals, especially for radios that lack these built-in functions.

### Does RST Scope have ads?

Yes, RST Scope contains advertisements. As it is a free application, advertisements are displayed to support its development and maintenance.

### What devices does RST Scope support?

RST Scope is available for iPhone and iPod devices. It is designed to run on Apple's mobile operating systems.

### How often is RST Scope updated?

The latest version of RST Scope is 2.7.0, last updated on December 27, 2025. This indicates a recent update, suggesting ongoing development and support.

### Can RST Scope record audio?

Yes, RST Scope includes a recording and playback function for input sound. This allows users to capture and review audio signals received through the app.

### What is the frequency resolution of RST Scope?

The frequency resolution for RST Scope is fixed at 40Hz. This provides a specific level of detail for analyzing the audio frequency spectrum.

### How can I switch between USB and LSB modes in RST Scope?

You can switch between USB (Upper Sideband) and LSB (Lower Sideband) modes in RST Scope by performing a Left or Right swipe on the screen.

### What is the user rating for RST Scope?

RST Scope has a perfect rating of 5.0 stars from 1 rating. This indicates a highly positive initial user reception.

## Version history (last 5 releases)

### 2.7.0 — 2025-12-27

We updated the operating stability and display format.

### 2.6.0 — 2023-05-01

Updated Admob SDK.

### 2.5.0 — 2023-02-18

Reviewed the drawing area according to the display size.

### 2.4.0 — 2022-12-07

Updated info.plist file.

### 2.3.0 — 2021-06-12

Fixed a bug.

## Apps similar to RST Scope

| App | Rating | Price | Category |
| --- | --- | --- | --- |
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| [Amateur Radio Toolkit 2025](https://appshunter.io/ios/app/amateur-radio-toolkit-2025/id6737146858) | 2.7 (10) | Free | Utilities |
| [niliBOX](https://appshunter.io/ios/app/nilibox/id6740749067) | — | Free | Utilities |
| [QTH Grid Square Locator](https://appshunter.io/ios/app/qth-grid-square-locator/id6738007254) | — | Free | Utilities |
| [On-Air Net Scraper](https://appshunter.io/ios/app/on-air-net-scraper/id1536271710) | 4.4 (13) | Free | Utilities |

## More apps by koji kamogawa

- [UkeDrum](https://appshunter.io/ios/app/ukedrum/id1488210714)
- [RST 599](https://appshunter.io/ios/app/rst-599/id1488919851)
- [WabunMorse](https://appshunter.io/ios/app/wabunmorse/id1490745806)
- [音耳せん](https://appshunter.io/ios/app/id1496478545)
- [RST 599 Pro](https://appshunter.io/ios/app/rst-599-pro/id1497452984)
- [RST 599x](https://appshunter.io/ios/app/rst-599x/id1498597799)

All apps by koji kamogawa: https://appshunter.io/developer/1488210713

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-08-22.*