audio filter

QNEWS Ham Radio News - Daily updates to the weekly QNEWS Ham Radio News service in text realaudio and RF

PE1PKU Peter - technics, radio astronomy, great links, duplex filter

EI4IX Dave - Dedicated to 50MHz and 144MHz. Online 2m and 6m logs. Real Audio sound clips of Tropo, Aurora, Sporadic E, Meteor Scatter, TEP and F2 Propagation.

Ham Radio Community Chapter Priority listing - Ham radio webcam live, solar updates, radio mods, satellite images, audio and video interactive, polls, links, constant events, weather, qrz database, by kd4sai

N1EU's Web Site - Original articles and useful hf links for contesting, TopBand 160M, FT-1000MP, Ten-Tec, SSB Audio, Mods and WriteLog

Remote controlled receivers  ^pop - Use real audio streams to listen to Hf and VHF stations around the world via remote controlled receivers connected to the web.

US Police Scanner  ^{updated  pop} - Live, 24-hour audio broadcasts of police scanners in major cities around the United States.

VK2FLR DX Sounds Archive - Real Audio files containing interesting examples of VHF DX propagation from Sydney, Australia

Gisela Dierking NF/HF-Technik Germany - Many interessting accessories, like unversal audiofilter, Mixer interface for sound card, highvoltage powersupply,accessories for 706, hamradio vacation, and more

Industrial Communication Engineers - RF parts, filters, rf switching products.

Ham Radio & DSP - Related histories, facts and opinions by EA2BAJ, includes example of PSK MT63 QPSK audio files in wav file

Scanrec Scanner Recorder - Scanner Recorder (Scanrec) is a free audio recorder that is primarily designed to record speech. It has a VOX control that allows the user to save disk space when no sound is present in the signal. Since FM communications has such an effective squelch, the recorder works best with FM. HF ham bands and World Band radio have such a poor signal to noise ratio that the VOX gate on Scanrec might not be very easy to set.

Vox Recorder  ^pop - 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. Vox Recorder has been designed in particular for radio-scanner hobbists.

QSO Manager - HF QSO/QSL/Award managment, ADIF Import/Export, full version free to everybody. Requires Access 97 or Access 2000 (with JPEG and TIFF filter installed), screen resolution 800x600/1024x768

BeaconSee - BeaconSee shows you, in real time, worldwide HF band openings on your PC. Analyses the audio signals from your radio, which is tuned to the NCDXF IARU HF beacon network and shows you the signal strength received from each of the 18 beacon transmitters as a plot of frequency spectrum against time.

Free programmable DSP-Filter  ^pop - Free programmable LOW/HIGH/BANDPASS FIR filter in the audio range 0-4kHz

Voice Descramble - This program descrambles band inverted encrypted transmissions, usually found on VHF/UHF. It uses a NCO (numerical controlled oscillator) to re-produce the originally inverted audio band.

DSPFilter - MM Hamsoft  ^pop - Freeware DSP filter by JE3HHT

SSB Pileup player - It plays back max 10 WAV audio data as one Real SSB Pileup Windows98/NT4

RemIcom-B - Freeware RemIcom-B is a very simple ICOM remote program. Display of current frequency, mode and filter ITU HF Band assignment (ITU Region 1, 2 and 3 selectable) HAM HF Band usage analog frequency band display

Spectra - Accurate spectrum analyzer in the range 0 - 2500 Hz, makes an accurate FFT analysis of an audio signal coming from the soundcard

Vox Actuated Recorder for Windows - 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.

SSB and CW Filter - A pdf file with schematics of an ssb and cw filter AF amplifier

Mode J Desense Filter - This type of filter can be used in a Mode J satellite station (uplink on 2m, downlink on 70cm) to reduce the problem of the uplink signal desensing the receiver

Toroid Pro - Designed by microwave engineers to provide filter, radio,microwave and Ham radio engineers with all relevant information of an inductor and core at his or her finger tips