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Presented here is a transceiver to computer sound card interface complete with automated transmit key function. A sound card interface is simply the audio coupling of a computer soundcard and a transceiver to allow various computer applications that send and receive SSTV, RTTY, PSK31 and other similar modes based on soundcard generated signals.

Vsound is a Linux software which allows you to digitally record the output of another program. The recorded output can be saved to a WAV file or can be transferred into another software. It's basically an audio transfer cable software.

MultiKeyer is a dedicated computer keying program designed for amateur radio operators engaging in specialized operating activities such as Earth-Moon-Earth (EME) and Meteor Scatter, as well as general contest operations. It provides distinct modes for both CW and Phone transmissions, enabling automated message sequencing and playback of pre-recorded audio files. The software's interface shares a similar "look and feel" to the popular WSJT Meteor Scatter/EME program, facilitating ease of use for operators familiar with that platform. For CW operations, MultiKeyer offers an EME Auto mode for sending timed messages crucial for EME and Meteor Scatter, alongside a Contest mode that handles automatic CQ calls and preprogrammed messages. On the Phone side, it features a Sequenced Phone mode for transmitting prerecorded .wav files during Meteor Scatter events and an Auto Phone mode for contest use. The program leverages serial COM ports for CW and PTT signaling, and the soundcard for .wav file playback, with configurable PTT interrupt options. MultiKeyer integrates with TRX-Manager for PTT and CW keying, and can send callsigns for logging. It also supports WSJT-style "callsign.txt" files for lookups and adheres to the SO2R protocol for parallel port connections. Designed for Windows 98 and NT, it generally functions on Windows 95, ME, XP, and 2000, requiring a 133 MHz Pentium-class processor.

Vox Recorder is a Windows utility wich allows recording sound from an audio source only when an audio signal is present; its main purpose is to avoid the recording of the silence eventually present at the input.

Windows freeware database containing frequencies, locations, and a small logging program capable or recording audio

The ICOM IC-7300 is a cutting-edge HF transceiver that has garnered significant attention since its release. This review, published by ARRL in QST, provides an in-depth analysis of its features, performance, and usability. The IC-7300 is known for its direct sampling technology, which enhances its sensitivity and selectivity, making it a favorite among amateur radio operators. The review covers various aspects, including the user interface, audio quality, and overall operational capabilities, providing valuable insights for both new and experienced hams. In addition to its technical specifications, the review discusses the IC-7300's performance in real-world scenarios, such as DXing and contesting. It highlights the transceiver's ability to handle weak signals and its versatility across different modes. The review serves as a helpful guide for those considering the IC-7300 for their station, offering a balanced perspective on its strengths and potential drawbacks. Overall, this review is an essential resource for anyone interested in the ICOM IC-7300 and its place in the amateur radio landscape.

Recorded scanner radio traffic from police and fire department communications. Stockton Police scanner recordings of pursuits, fights, shootings, officer involved shootings, in progress high intensity calls.

The Adonis Electric Co., Ltd. catalog details a range of amateur radio microphones, including mobile, desktop, and bike-specific models, alongside essential accessories. Featured products include the _FX-6_ flexible microphone and various interconnecting cables designed for seamless integration with transceivers from Icom, Yaesu, and Kenwood. The catalog also presents specialized items like microphone selectors, alternator noise filters, and peripherals such as voice memory units and double VOX controllers, enhancing operational flexibility for hams. These products are engineered to improve audio clarity and operational convenience for amateur radio operators, particularly in mobile and fixed station environments. The inclusion of conversion codes ensures compatibility across major transceiver brands, simplifying setup. The alternator noise filter addresses common mobile RFI issues, contributing to cleaner signal reception and transmission, which is crucial for effective DXing and contesting.

Xcorder is a windows Freeware audio recorder written by MM0BFF, designed to work mainly with radio receivers but may be used also in several different ways for audio recording needs.

About numbers stations, and their criptic transmissions, where to listen to them and some audio recording samples by fascinating shortwaves

EME operation news, typical moonbounce audio recordings

A page about fascinating Very Low Frequency and natural radio, with lots of streaming audio links from remote receivers. Some experimental stereo pairs around the world.

Deciphering weak or noisy **CW** (Continuous Wave) signals often presents a challenge for amateur radio operators, particularly in contest environments or during DXpeditions. CWLab04X addresses this by providing a software solution that leverages **DSP** (Digital Signal Processing) capabilities of a soundcard to decode Morse code. It functions as both a receiver and a sender, supporting traditional CW and a unique "CCW" mode designed to enhance copyability of signals struggling against high noise floors. The program offers two installation methods: a Windows-specific installer for straightforward setup or a zipped package compatible with Windows and Linux systems running Wine. Users must first download and review the accompanying PDF documentation, CWLab04.pdf and CWLab04_Hardware.pdf, which detail the software's operation and the necessary soundcard interface circuit. The hardware PDF outlines a direct connection from the receiver audio output to the soundcard input, with optional conversion of the soundcard output for hard-keying or microphone input. CWLab04X is intended as an operational aid rather than a replacement for skilled human copy, particularly highlighting the effectiveness of its CCW mode in adverse signal conditions. The software was last revised in April 2009, with installation requiring the LV Runtime 602.

Have you ever wanted to listen in on a serious SO2R DX contest effort? hear what the low bands sound like from New England? enjoy a contest without having access to a radio? This is your chance!

The page provides a utility to record QSOs for amateur radio operators, allowing them to send the recorded signal back to the other station. It addresses challenges with VOX capability in radios and offers solutions for different radio models.

JaRec is a multi-platform Java application which can be used to control your own CAT enabled transceiver (with support for audio) using a Serial/USB Serial/Bluetooth or network connection. jAReC can act as both a server and as a client. The PocketRxTx Android application can be used as a client securely to connect over the network and control (CAT) your radio transceiver remotely via jAReC server over the Internet or local LAN, with bi-directional audio support.

CWRX, a freeware Windows application, decodes Morse code (CW) signals directly from a sound card's audio input, presenting the decoded text on screen. It supports various receive bandwidths and filtering options, allowing operators to optimize signal reception in different QRM conditions. The program's core functionality focuses on robust CW decoding algorithms, crucial for weak signal work and contesting environments. Developed by OZ1IVA, Lars Harbo, this utility provides a straightforward interface for real-time CW interpretation. It integrates basic logging capabilities, enabling users to record decoded transmissions for later review or contest submission. The software is specifically tailored for the Windows operating system, ensuring compatibility with common shack computer setups. Its design emphasizes ease of use for amateur radio operators seeking a dedicated CW decoding solution. The program's small footprint and direct functionality make it a practical tool for both casual listening and more intensive operating sessions, without requiring extensive system resources.

The resource provides a specific wiring schema for adapting a Kenwood PG-4S cable to be compatible with Kenwood TH-F6A, TH-F7E, and TH-G71 handheld transceivers. It details the necessary pinout modifications, illustrating how to convert the existing PG-4S cable, which is typically used for data transfer or programming, into an interface cable for these specific HT models. The content focuses on the electrical connections required to achieve this cross-compatibility, presenting a practical solution for hams who already own a PG-4S and wish to avoid purchasing additional dedicated cables for their TH-F6A, TH-F7E, or TH-G71 radios. The adaptation process involves reconfiguring the connections to match the audio and data port requirements of the target handhelds. This technical information is particularly useful for operators seeking to interface their Kenwood HTs with sound cards for digital modes or for programming purposes, leveraging existing hardware. The page offers a direct, functional approach to hardware modification, emphasizing reusability and cost-effectiveness for Kenwood transceiver owners.

Presents the Aceco product line, focusing on their range of frequency counters, RF testers, and specialized bug finders. It details the capabilities of the _FC-1000_ and _FC-2000_ series as user-friendly, affordable frequency counters operating up to 3 GHz. The resource also highlights the _FC-3002_ as a portable RF finder capable of automatically tuning _ICOM CI-V_ or AOR scanners to detected signals, emphasizing its utility in secure monitoring. Furthermore, it describes the _FC-5000_ series as a wideband FM receiver that rapidly locks onto and demodulates FM signals, outputting audio through a built-in speaker, making it suitable for counter-surveillance and radio communication testing. The page provides technical specifications and operational distinctions for each product series. The content is structured to differentiate between the core functions of frequency measurement, signal tracing, and FM signal demodulation across the various models. It clarifies that these devices are not traditional scanners but offer faster signal acquisition for specific applications. The information is presented in both English and German, with a note indicating ongoing translation efforts for the German sections. The resource serves as a product catalog and technical overview for Aceco devices, distributed by WiMo Antennen und Elektronik GmbH, providing essential details for potential buyers interested in RF measurement and surveillance tools.

Processing a single RTTY signal from a transceiver's 3-kHz audio, GRITTY employs _Bayesian statistics_ for superior decoding accuracy compared to traditional trial-and-error methods. This approach not only decodes 5-bit Baudot codes but also calculates the probability of error for each bit, enabling features like color-highlighting unreliable characters and smart squelching based on error probability rather than signal amplitude. This allows decoding of very weak signals while suppressing strong, undecodable interference, resulting in minimal garbage text. The program intelligently analyzes decoded text, comparing similar callsigns bit by bit and merging probabilities using the Bayes formula. This often allows GRITTY to determine the correct callsign and place it on the call stack even when all received copies are corrupt. The same methodology is applied to correct errors in exchange numbers and CQ/DE keywords, and to fix incorrect shift states. GRITTY offers an open API interface, documented in its Help file, for integration with other programs, allowing them to receive decoded data and mouse click events.

Minimal interface circuits for receiver and transmitter audio, also for PSK31

This online guide details the microphone pinout for the Kenwood TR-7950 transceiver, specifically addressing the wiring configuration for a dynamic mobile microphone with a **500 Ohm** impedance. It provides a pin-by-pin breakdown for the 6-pin microphone connector, identifying the function of each active pin. The resource specifies that Pin #1 is for the microphone audio (white wire), Pin #2 controls the _PTT_ (black wire), Pin #3 activates the memory down function (blue wire), and Pin #4 controls the memory up function (red wire). Pin #6 is designated as the ground connection, while Pin #5 remains unused in this configuration. The document focuses on the physical wiring necessary to restore microphone functionality to the Kenwood TR-7950, a transceiver capable of **45 watts** output on the _2m band_. It directly addresses the technical challenge of re-establishing correct electrical connections after microphone wires have been disconnected from the connector. The information facilitates proper microphone operation for simplex QSOs and other voice communications. DXZone Focus: Online Guide | Microphone Pinout | Kenwood TR-7950 | PTT Wiring

Lage collection of 6 Meters and 2 meters QSOs, recorded in real audio format by OE3MWS

Shortwave Monitoring Station in Berlin: DX news, HF propagation, greyline, DRM news, QSL gallery, audio recordings and more

Maker of QRP Kits, QRP CW receiver and transmitters, audio CW Filters, antenna tuners, dummy loads, and morse code practice oscillator

For amateur radio operators engaged in **radio direction finding** (RDF) and **transmitter hunting** (T-hunting) activities, this resource provides a catalog of printed circuit boards (PCBs) for constructing various DF and foxhunt-related projects. The offerings include PCBs for 80-meter fox transmitters and receivers, UHF fox transmitters with audio recording capabilities, and several designs for general-purpose radio direction finders. Specific projects like the "Simple 80M ATX-80 Transmitter" and the "N0GSG DSP Radio Direction Finder" are listed, along with attenuator boxes and specialized components for Doppler DF systems. The catalog details PCBs for projects published in prominent amateur radio magazines such as *73's*, *CQ*, *QST*, and *PE*, indicating their origin and design pedigree. For instance, the "Montreal Fox Controller" is sourced from the *Homing-In* column by Joe Moell, K0OV. The resource also lists components for advanced Doppler DF systems, including main boards, LED display boards, and antenna switch boards, with options for programmed PIC microcontrollers. Pricing for each PCB is provided, allowing hams to acquire the necessary components for their DIY RDF endeavors.

Hidden transmitter hunting, often called fox hunting or Amateur Radio Direction Finding (_ARDF_), presents a unique challenge for radio amateurs. This resource details the _PicCon_ controller, a specialized device designed to automate the transmission of signals for such events. It integrates with a standard radio transceiver, functioning similarly to a packet radio TNC, by controlling the Push-To-Talk (PTT) line and injecting audio tones or modulated CW Morse code into the microphone input. The _PicCon_ unit is field-programmable using DTMF tones received via the radio, storing all settings in EEPROM for power-off retention. Its compact design and low power consumption (a few milliamps from a 7-35VDC source) make it suitable for remote deployment. An onboard LED indicates operational status, and a push-button allows manual start/stop of transmissions without DTMF. Typically supplied as a kit, _PicCon_ includes a PCB, components, and a comprehensive manual (available in HTML, RTF, and PDF formats). The kit provides a six-conductor interface cable, but users must supply radio and power plugs due to varied configurations. Byon, _N6BG_, developed this controller, which is available from the Byonics website.

Beacons recorded audio files by kl7fdq

DarkIce is a live audio streamer. It records audio from an audio interface (e.g. sound card), encodes it and sends it to a streaming server. Works on Linux and MacOSX

EchoLink and IRLP Internet Radio Linking Project Node's, Hurricane Watch Audio Feed's and Info, Live Scanner/Other Feed's from the USA, Local Ham Frequencies, Online Receiver's, Shoutcast Live Audio Feed's from the USA, Southern California Frequencies and more

Audio files to help identify rf noise (rfi). Identify the RFI that interferes with your reception. RFI Noise identification.

This tutorial provides step-by-step instructions for setting up the ICOM IC-7300 to work with WinLink and WinMor. The process begins with downloading the necessary USB driver from ICOM Japan, followed by configuring the radio settings through the menu. Key settings include selecting the correct output and data modes, as well as ensuring the USB serial function is properly set. Once the radio is connected to the PC via USB, the drivers will install automatically, allowing for seamless communication. After confirming the installation of the USB Audio CODEC and COM port, users are guided to download the RMS Client Software for WinLink. The tutorial emphasizes the importance of understanding the WinLink system and provides links to additional resources for setup. Finally, it details how to configure the WinMor modem settings, ensuring the ICOM IC-7300 is ready for effective digital communication. This guide is essential for operators looking to enhance their digital capabilities using the IC-7300.

This project hereby presented is a complete HAM radio simplex 'smart' repeater, built around a Motorola GM-350/950, Arduino NANO board and a WINBOND audio recording integrated circuit

To aid in learning and improving Morse code proficiency, this resource offers an extensive collection of downloadable MP3 audio files. The content includes character practice groups, common words, punctuation, and full-length novels, all rendered in CW. Speeds incrementally increase, catering to both beginners and those aiming to build speed, with options for _Farnsworth_ spacing at lower WPM and standard spacing for higher rates. The resource also provides a Perl script, `gus_morse.pl`, allowing users to generate custom audio files from UTF-8 text. Users can download archives of sequential MP3 files, with options for English, German, Spanish, Esperanto, and Italian content. The audiobooks progress from **5 WPM** to over **40 WPM**, with some archives offering _omnibus_ collections of multiple works. The site emphasizes the importance of consistent daily practice and patient aural observation to develop procedural memory, moving beyond conscious dit and dah counting to direct character recognition. It also details the transition from Farnsworth to normal spacing, aligning with FCC and ARRL recommendations.

Award-winning MP3 Recorder software for Windows 7 and Windows 8 will capture streaming audio without using Stereo Mix feature.

Kenwood Ibérica's online presence details their extensive product line, including the NEXEDGE NXDN and DMR digital radio systems, alongside traditional analog offerings. The site categorizes transceivers by mode, such as HF / Todo Modo (All Mode), and portable/mobile VHF/UHF units, catering to various amateur radio operating preferences. This includes specific accessories like batteries, chargers, microphones, and programming cables, essential for maintaining and customizing radio equipment. The Spanish portal also highlights Kenwood's broader electronics portfolio, extending beyond amateur radio. This encompasses car electronics, featuring navigation and multimedia systems, as well as marine receivers and speakers. The product range covers everything from CD and CD-less car receivers to power amplifiers and DashCam/RearCam solutions, demonstrating the brand's diverse market reach. Beyond communications gear, the site presents home audio systems, including all-in-one receivers and portable party speakers. This breadth of offerings underscores Kenwood's long-standing presence in both the consumer electronics and two-way radio sectors, providing a centralized resource for product information and support.

The HotPaw Morse Code Decoder application for macOS processes audio input to transcribe Morse code characters into text. It presents both an audio spectrum graph and a tone amplitude graph, which aid in configuring a narrow band audio filter. Operators can set the audio filter for tone frequencies between 400 and 1600 Hz, optimizing reception for various CW signals. The software offers user-configurable settings, including WPM dot/dash speed detection, a noise threshold level, and the option to use Farnsworth timing for inter-character spacing. The Morse code WPM detection automatically adapts from approximately 8 to 40 WPM, with a lock feature for the estimated speed. A High Speed WPM Mode is available for code speeds ranging from 40 to 80 WPM, catering to faster CW operators. The application's decoding performance is influenced by signal level, signal-to-noise ratio, frequency and WPM stability, keying quality, and proper configuration, with an initial learning phase required for WPM estimation to stabilize. An external microphone or line-in may be necessary for optimal performance on some MacBook models to mitigate fan noise or room reverberations. Version 1.4.4, updated on November 11, 2021, includes compatibility improvements for newer macOS releases. The developer, Ronald Nicholson of HotPaw Productions, does not collect any user data from the application.

The Icom IC-7300 is a popular HF transceiver among amateur radio operators, known for its advanced features and ease of use. However, integrating it with software like Ham Radio Deluxe (HRD) can be challenging due to compatibility issues. This guide provides step-by-step instructions on how to configure the IC-7300 to work seamlessly with HRD 5.24, the last freeware version available. It covers the installation of necessary drivers, setting up virtual COM ports, and configuring audio settings for digital modes. To begin, users must download and install the Icom USB driver, which creates a virtual serial COM port for communication between the radio and the computer. The guide details how to check for this new port and adjust the CI-V address settings to ensure proper communication. It also explains how to set up the soundcard settings in HRD for digital modes, allowing operators to transmit and receive audio effectively. Following these instructions will enable IC-7300 owners to maximize their radio's capabilities with HRD.

Over 100 amateur radio beacon audio files are presented, offering a direct auditory experience of propagation conditions across a wide spectrum of frequencies, from 1.8 MHz to 47 GHz. These recordings, primarily captured by IW3FZQ and IK3NWX, document signals from beacons such as DK0WCY, IY4M, GB3RAL, and S55ZRS, providing a valuable resource for **propagation study** and **beacon monitoring**. Each entry in the list specifies the beacon's callsign, its operating frequency in kHz, and the recording operator. This compilation includes signals from beacons located in various grid squares like JN55VF, JO44VQ, and IO91IN, illustrating diverse geographical origins. The frequencies covered span the 160m, 80m, 40m, 30m, 20m, 17m, 15m, 12m, 10m, 6m, 4m, 2m, 70cm, 23cm, 6cm, 3cm, 1.2cm, and 6mm amateur bands. Users can listen to these recordings to identify characteristic beacon tones and observe signal strength variations. The resource also invites other radio amateurs to contribute their own beacon audio files, fostering a collaborative archive of propagation data. The last update to this collection was on March 24, 2009, indicating a historical snapshot of beacon activity. Accessing the files requires the Real Player software.

Breakaway Pipeline allows you to send audio to or from another program on the same computer. This will permit to forward audio streams, virtually like connected via a cable taken form any radio receivers, like online web sdr or your digital modes receiver like WSJT-X or fldigi to anther application running on the same PC.

VK3OT audio recorder qsos.

One hundred and fifty words per minute (WPM) is a configurable speed setting in this online Morse code translator, which facilitates bidirectional conversion between plain text and **Continuous Wave (CW)**. Users can input text to generate corresponding Morse code, or enter Morse code using dots and dashes to receive a text translation. The tool supports various alphabets, including Latin, Cyrillic, Ukrainian, Hebrew, and Arabic, broadening its utility for international communication. The platform offers multiple output methods for the generated Morse code, including audible playback, visual flashing, and device vibration. Advanced configuration options allow for precise control over the sound's pitch (frequency), volume, and overall speed, including a **Farnsworth speed** setting. This flexibility enables users to customize the learning or communication experience to their specific needs. Additional features include the ability to save the generated Morse code audio as a WAV file and to create shareable links for messages, which can be sent with or without the accompanying text. The interface is entirely web-based, built with HTML5 and JavaScript, ensuring broad compatibility across modern browsers.

Demonstrates the capabilities of CW_Shark, a dedicated 32-bit Windows application for Morse code operations. This software facilitates the analysis, decoding, and encoding of CW signals, providing hams with a versatile tool for various aspects of amateur radio communication. It supports four distinct modes: Decode Only, Keyboard QSO, Straight or Paddle Key QSO, and Straight or Paddle Key Practice, catering to different user needs from passive listening to active keying. Operators can utilize the Decode Only mode for signal analysis, while the Keyboard QSO mode allows for text-based interaction. The Straight or Paddle Key QSO mode offers a direct interface for traditional keying, enabling real-time communication. For skill development, the Straight or Paddle Key Practice mode provides a structured environment to hone Morse code proficiency. CW_Shark integrates essential functions for CW enthusiasts, supporting both learning and active participation in Morse code exchanges. Its focused design aims to assist operators in mastering and enjoying the art of _CW communication_.

The WaveNode WN-1 is a precision, full-featured Amateur Radio Station Monitoring System which now includes Audio Announcing for RF power, SWR, and DC monitoring using HF and UHF remote sensors.

For over 20 years, bhi Ltd has specialized in digital signal processing (DSP) technology to mitigate noise and interference across various radio channels. Their product line, including the _ParaPro EQ20 Audio DSP_ units, focuses on enhancing receive audio quality, even for operators without significant noise issues, by offering precise parametric equalization to suit individual hearing preferences. The core offerings are noise-cancelling speakers and in-line modules, specifically engineered for amateur radio applications, but also adapted for commercial, PMR, and marine radio systems. The company provides audio demonstrations, such as a 20m SSB example and a 14MHz band filter comparison, allowing users to hear the effectiveness of their DSP units against common QRM sources like plasma TV interference or diesel engine noise. Located in Burgess Hill, West Sussex, UK, bhi Ltd emphasizes clear voice communications, aiming to remove unwanted noise and leave only intelligible speech.

This resource provides a unique historical audio archive of 50 MHz DX contacts, documenting significant F2 and Es propagation events experienced by PA2S (formerly PA2HJS) since 1978. The collection includes recordings of beacons and two-way QSOs with stations across North America, South America, Asia, Australia, Europe, and Africa. Specific entries detail contacts with rare DX entities such as ZS6PW, VE1AVX, C5AEH, J52US, TR8CA, LU8MBL, VK8ZLX, and various Japanese stations, often noting the mode (SSB or CW) and propagation type. The archive also highlights challenging pile-up situations and frustrating near-misses during major openings. The recordings, initially in RealAudio format for solar cycles 21 and 22 and later in MP3 for cycle 23, offer a practical illustration of 6-meter band conditions over several solar cycles. The content allows hams to listen to actual signals from different continents, observing signal characteristics like typical TEP fading from 5H3RA or strong F2 backscatter from OZ1BVW. It provides a comparative perspective on propagation effectiveness between solar cycles, noting that cycle 23, while not as robust as previous cycles, still yielded interesting openings. The archive serves as a valuable educational tool for understanding real-world 50 MHz DXing and propagation phenomena.

The direct conversion receiver described consists of only a bandpass filter, mixer IC, VFO and audio filter. With only 22 parts, this simple circuit should take a few hours at the weekend to construct.

Audacity is a free, easy-to-use, multi-track audio editor and recorder for Windows, Mac OS X, GNU/Linux and other operating systems. The interface is translated into many languages.

Details the construction of an **HF converter** designed by M1GEO, George Smart, specifically to extend the frequency range of the FunCube Dongle Pro (FCD) for amateur radio reception. The FCD natively covers 64 to 1,700 MHz, but this project enables reception from 0 Hz to 64 MHz by up-converting signals to the FCD's operational range. It employs a **double-balanced mixer** with a 100 MHz local oscillator (LO) to translate incoming HF signals; for instance, a 1 MHz signal appears at 101 MHz within the FCD's passband. The design incorporates a 7th-order Chebyshev low-pass filter with a 62 MHz cutoff frequency at the input to mitigate image frequencies, ensuring cleaner spectral presentation. George provides the schematic, PCB masks, and Gerber files for replication, noting that Far Circuits also offers PCBs. The resource includes test results for the low-pass filter and measurements of LO leakage, identifying -36.8 dBm at 100 MHz as a potential sensitivity concern. M1GEO discusses potential improvements, such as adjusting the mixer's LO drive, adding a balance pot, or incorporating a post-mixer high-pass filter to reduce LO breakthrough. Audio recordings from 40m and 17m demonstrate the converter's performance with WRplus SDR software.

A simple free running oscillator oscillating at the receiver\'s IF (intermediate frequency) beats with the incoming signals in either CW or SSB and the resultant audio frequency goes to the AF amplifier.