digital audio

45SD105 Vlada - Personal web site of a freebander, info on 11m digital modes, pictures of antenna projects

VU2LFA ham radio in india - This site is basically for the begeners (SWL) of india. This site is supporting to digital communication for hams also.

Live online streaming for arizona - Listen to original audio content from Flagstaff, Coconino County and Northern Arizona. Streaming Police scanner by azradiowaves.net

Contest audio file - MP3 file recording a QSOs with SP5CKA and SN7N (SP7PS) in SP DX Contest 2001 on 40m (recorded by SP7PS)

About digital modes - The digital modes provide a wonderful opportunity for those of us who would like to work on the HF bands but find CW too difficult and SSB phone prohibitive because of interference problems. The digital modes are easy to set up and get operating, require low power and a narrow band.

Recommended frequencies for digital modes - Active digital mode frequency list compiled by Jason Buchanan - N1SU

CQ SSTV de KB4YZ - Amateur slow scan television and digital sstv by KB4YZ

Kenwood ts-2000 and packet/digital mode - Using the TS-2000 for packet and digital modes. How to connect the Kenwodd TS2000 to TNC

Rocket Radio UK - UK based suppliers of CB, amateur radio equipment and DAB digital radios. Other products include antennas, base and handheld scanners, and accessories including microphones, books.

Transeltech - Communications products for hobbyist, industry and law enforcement, antennas, electronic kits, rf audio connectors, scanners. Ohio USA.

HamCalc v1.3  ^pop - By G4VWL, HamCalc is collection of calculators for radio amateurs: Antenna ERP calculations. Attenuators. Audio Filter design.Coil Winding. Decibels. Great Circles map and calculator HF Filters HF Traps Metric conversions OP Amps QRA Locator to Latitude/Longitude (and back) Radio Horizon calculator Resonance Satellite orbit calculator Timer calculations (555 timer)Zener Diode calculations

WEaudio recorder - WEaudio was born as a program to record activity on VLF band, it can records audio file on HD as long as you want within prefixed pauses. It can starts record at the hour you want to monitor.

WD6CNF DSP Filter - Audio Digital Filter, two bandpass filters, three notch filters, two noise filters graphical setting of filter center frequency and bandwidth Drag vertical lines on top of signal, Microphone input, speaker output Mono, 5 kHz bandwidth

Konfabulator - DX Cluster Priority listing - Freeware windows XP and MacOSX konfabulator widget dedicated to Amateur radio operators, is an easy interface to DX-Summit the ham-radio DX Cluster. DX cluster spots represents live ham radio communication connections, and are an invaluable resource for amateur radio operators. Users can choose Bands or operating modes like digital emissions, QRP IOTA and more. Spots are refreshed automatically and refresh rate can be set by users, with a minimum of 100 seconds.

DigiACE - DigiACE is an experimental Digital SSTV system. The latest version is posted as DigiACE.zip DigiACE uses the RDFT transmission system with some enhancements

CW Decoder  ^pop - This program allows CW operators to copy CW code with a computer. The decoded CW is displayed as text or can generate a side tone. There is a spectrum display of the audio with a sliding cursor to select a particular audio for decoding. The program also allows for keying a transmitter from the keyboard with full CW break-in operation.

FNpsk - The FNpsk program provides for accurate message handling and net management of amateur radio emergency communications using the PSK31 or PSK63 digital formats

TCube - TCUBE is a combination of a Spectrum Analyzer and a Two Tone Generator, with optional quadrature outputs. It can be used for measuring the intermodulation behavior of an audio circuit, and as a general purpose tool

RightMark - RightMark Audio Analyzer

SpectraScope - SpectraScope is a simple Windows interface program allowing your computer to view up to two audio waveforms in either the time or frequency domain. The program is a Windows soft panel operating as a dual channel oscilloscope and spectrum analyzer. The useful frequency of operation is 20 to 10,000 Hz in the time domain and 20 to 20,000 Hz in the frequency domain. The program uses the computer sound card to capture the audio input.

WD6CNF Voice keyer - Audio voice keyer Microphone input, speaker output Live microphone enable Record/play audio from twelve memories Display text of recorded audio Transmitter keyed via serial (com) port Loop (with variable delay) audio output

HamView - A freeware program to dig out weak signals buried in noise, functionally similar to the excellent FFTDSP of AF9Y, but with the added bonus of real time audio filtering of the incoming signals. Just point and click with the mouse, and the selected signal will stand out from the QRM and noise.

Audio spectrum analyzer  ^pop - Analyzes audio from 10 Hz to 20 kHz, input from microphone or wave file, Variable sample rates (8000 Hz, 11025 Hz, 22050 Hz, 44100 Hz) Variable transform sizes (1k, 2k, 4k, 8k) Upper and lower limits adjustable Continuous, averaged, peak hold

QRM and noise reduction Priority listing - You will find on these pages my experiences and results on antennas and local/non-local QRM/noise reduction. Using a broadband vertical active magnetic loop and a home made / designed broadband amplifier. Two vertical magnetic Alford loops are used in an array. Analog and Digital Signal Processing and a dual phase coherent Software Defined Radio (SDR) are used. By PA0SIM

A 80/40m Direct Conversion HF Receiver with DDS VFO - Juha (OH2NLT) and Matti (OH7SV) have designed JUMA-RX1, an award winning 80/40m direct conversion HF receiver with highly accurate direct digital synthesis VFO. The receiver is very compact, because it constructed using surface mount components. No coils need to be wound to construct this receiver!