Tagged: shortwave

DXLens: An iOS App Combining Shortwave Schedules, Propagation Data and Public SDRs

Thank you to Muayyad for sharing news about the release of his iPad/iPhone-compatible application, 'DXLens', designed for listening to remote shortwave SDR receivers. DXLens also comes with features like aggregated shortwave schedules from multiple sources, and propagation data and reception forecasting to help users choose the right global receiver for the conditions. He writes:

DXLens is a newly released iPhone/iPad application built around connecting the shortwave schedule and SDR listening workflows.

A listener can begin with a broadcast from EiBi, Aoki/NDXC, or HFCC, inspect the schedule-source evidence and transmission path, review modeled propagation context and assumptions, and then request compatible public SDR receivers for the frequency.

From there, DXLens provides a native listening workspace with live spectrum and waterfall, frequency/mode/bandwidth controls, receiver switching and reconnection, SDR presets, signal/session information, and local recording.

The app also includes Path Atlas, ionospheric and space-weather context, RF Environment tools, Model Audit, alerts, Custom listening views, and a structured reception logbook.

An important design boundary is that scheduled activity, propagation modeling, public receiver availability, and actual reception are kept separate rather than being presented as equivalent evidence.

The app appears to connect to the KiwiSDR network, and also has support for personal rtl_tcp based receivers.

At the moment, the app appears to be free, with no in-app purchases. DXLens is available on the Apple App Store.

DXLens Screenshots
DXLens Screenshots

Wavelingo: Real-Time AI Shortwave Translation for the KiwiSDR Network

Thank you to Christophe (F4DAN) for writing in about his new project called Wavelingo, an AI real-time shortwave radio translator. The software currently works with the KiwiSDR web SDR network. Christophe has a live public example running at wavelingo.app, however, with a 60-second timeout due to hosting cost constraints. Christophe writes:

Are you listening to a QSO in a foreign language on your transceiver? Click on the closest SDR (KiwiSDR fleet for now, more SDR to come in the future), and get real-time translations.

I opened a telegram channel to share updates and feedbacks on this projects - and provide support.

The software is open source, with the code available on GitHub.

Wavelingo - Real time AI translationfor shortwave radio stations received via the KiwiSDR network.
Wavelingo - Real-time AI translation for shortwave radio stations received via the KiwiSDR network.

RadioWorld Magazine Article about Software Defined Radios for Shortwave Listening

The latest August edition of the RadioWorld Magazine has included an article by James Careless about the use of software defined radios for shortwave radio listening. RadioWorld is a magazine targeted towards radio broadcast owners, managers and engineers all over the world. The article explores SDRplay and RTL-SDR Blog V4 units from the perspective of a shortwave listener new to software defined radios, comparing them to his high-end Sangean ATS-909X2 shortwave digital receiver.

The article can be accessed freely from this link and is found on pages 18-21.

First page of the RadioWorld Magazine article on SDRs.
First page of the RadioWorld Magazine article on SDRs.

The SDRSharp ListenInfo Plugin

SDR# is a popular software defined radio program that is compatible with RTL-SDR, Airspy and several other SDR devices. One feature is the ability for third parties to develop plugins for the software.

One recently released plugin that is gaining popularity is the "ListenInfo" plugin. The ListenInfo plugin uses a publicly available database of shortwave stations to display frequency station info for the LW, MW, SW bands within the SDR# spectrum display.

If you've ever been browsing the shortwave bands and wondered where a station is broadcasting from, and what it's transit power, beam direction and transmit schedule are like, then this will be a very useful plugin for you.

SDR# ListenInfo Plugin
SDR# ListenInfo Plugin

Video on Receiving HF Signals with the RTL-SDR Blog V3

Over on YouTube TheSmokinApe has uploaded a video showing how to use the direct sampling mode on RTL-SDR Blog V3 devices to receive HF transmissions, such as the ham bands, short wave and AM broadcast. In the video he shows how to activate direct sampling mode in SDR#, and then goes on to show reception of a few HF signals.

We note that an appropriate HF capable antenna is required to receive HF signals. The multipurpose dipole kits we sell are for VHF/UHF reception only. A simple and low cost HF antenna could just be a long wire running through your house.

HF Ham Radio with RTL-SDR Made EASY!

TechMinds: Testing the GA-450 Portable HF Active Loop Antenna

Over on the Techminds YouTube channel, Matt has uploaded his latest video which is a review of the GA-450 portable HF active loop antenna. The antenna costs between US$60-$80 + shipping and is available on Chinese market sites like Aliexpress and Banggood. It's advertised as covering 2.3 - 30 MHz, and uses a very portable and sturdy 20cm stainless steel loop. The active base amplifier is powered via a USB-C connector, and it even has a built in lithium battery for portable field use.

In his review Matt shows the antenna in action, noting that it's performance is quite a lot better than expected for it's small size, but it can't compare to his large half-wave end fed antenna. He notes that it appears to work best from 7 - 21 MHz, but not so well below 7 MHz. Overall he recommends it if you're looking for a small sized loop antenna.

GA-450 Portable Active Small Loop HF Antenna

SDRUno 1.41 Released: Scheduler and ADS-B Plugins Added

Last week SDRplay released version 1.41 of their SDRUno software platform. SDRuno is the official software for the SDRplay line of low cost software defined radio devices. The main new feature is the addition of the scheduler facility which allows users to easily schedule recordings. This is great if for example you wish to automatically record a shortwave programs playing overnight.

SDRuno V1.41 was fully released today. It includes the much requested full scheduler facility which allows you to set up numerous recording events for your RSP. As well as providing all the expected calendar options (time of day, date, start and stop times, repeating options and so on), you can also set the ‘profile’ for each recording – this allows you to pre-set frequencies, bandwidths, demodulator options (AM/FM/USB/LSB etc.), choice of filters and antenna port selection. Additionally you can choose the settings for connectivity to other third party software or the running of a specific plugin.

Introduction to SDRuno 1 41 - Scheduler & Profiles (VID597)

The new version also includes a finalized version of their ADS-B aircraft tracking plugin. Last month TechMinds tested the ADS-B plugin beta, noting that it worked well, but there were bugs with the built in mapping feature. In the official tutorial video the ADS-B plugin is demonstrated and shows that the mapping problem is fixed.

SDRuno ADSB Plugin (VID599)

A Hi-Z to 50 Ohm Impedance Matching Transformer for Improving HF/SW Reception

Thank you to Mitsunobu for writing in and sharing news about the release of his new product which is a Hi-Z (high impedance) to 50 Ohm matching transformer. This transformer allows you to use small antennas such as short telescopic whips for HF/SW reception on software defined radios.

Generally for HF reception you would want to use a full sized antenna, which can be many meters long and certainly not portable. However, by using an high impedance transformer it becomes possible to use smaller portable antennas. Reception with a small antenna and transformer will still be suboptimal compared to a full sized HF antenna, however, if the signals are strong enough the transformer will allow you to receive them decently.

In the tests shown on his blog (in Japanese, use Google Translate) he shows how the transformer adapter can be connected to a small telescopic whip and Malachite DSP SDR for portable use. Later he also shows how the adapter can make our Dipole Kit antenna work well for HF on a RTL-SDR Blog V3 with direct sampling.  

The product is only available via Amazon in Japan. However, Mitsunobu notes that Amazon.jp offers international shipping. He offers the transformer by itself, and a version including a short telescopic whip antenna.

Hi-Z to 50 Ohm Antenna Transformer for HF/SWL