low pass audio filter

20m delta loop  ^pop - This antenna is fed for vertical polarisation, to give a low angle of radiation for DX and also a nearly omni-directional radiation pattern

G5RV multi-band antenna - Multi-band centre-fed antenna capable of very efficient operation on all HF bands, specifically designed with dimensions which allow it to be installed in gardens and other open spaces which accommodate a reasonably-straight run of 31.1m (102 ft) for the flat-top standard model.

Low reactance multiband center feed wires - An antenna system is more easily interfaced to a radio when the input reactance at the feedline terminals is low or close to series resonance

Rotatable delta loop - W2UP rotatable low band receiving delta loop

W5JI Boatanchor Haven - Dedicated to the Care and Feeding of BoatAnchors, includes some Drake catalogs, and 1968 Collins Mechanical filter catalog pages

AA9PW.com FAA and FCC Exam Practice - home of the AA9PW exam practice pages.This site is designed to allow you practice for the following FCC Radio and FAA Aviation licensing exams.

QRZ Ham Radio Exam Test - This testing system serves as a training aid to help amateurs and prospective amateurs in passing the FCC exams neccessary to obtain US amateur radio licenses.

Virginia Beach Police  ^pop - Live dispatch audio from the Virginia Beach Police Department by www.hrconnect.com

Virginia Beach Fire Department / EMS - Live streaming audio of the Virginia Beach Fire Department and EMS services by www.hrconnect.com

Norfolk Fire and Rescue - Live dispatch audio from Norfolk Fire and Rescue by www.hrconnect.com

Chesapeake Police Dispatch - Live dispatch audio from Chesapeake, Va police dept by www.hrconnect.com

Newport News Police & Fire Dispatch - Live dispatch audio from Newport News, Virginia by www.hrconnect.com

Low Power Radio Modules - Low power radio modules - supplying rf modules, rf transceivers, radiometrix transmitters receivers, low power radio modules, scada, frequency hopping, 900 mhz, wireless data transmission, data telemetry, gps modules & receivers and more

CW Operators' QRP Club Inc. - The CW Operators' QRP Club exists for those who enjoy low power amateur radio and homebrewing.

Morse Code For The Rest Of Us: Learn Morse Code quickly and easily. - Morse Code For The Rest Of Us: Learn Morse Code quickly and easily. Have fun with the Morse Code tutorial which is guaranteed to help you pass the FCC 5 word per minute test.

Radiopejlorientering - Radio Direction Finding - The Swedish ARDF page is mainly presented in the Swedish language, but some articles are in English.

PC to RTX interface - Schematics for IC-706, IC-718, IC-756PRO, TS-570, TS-870, and simple universal S.B. interface All three interfaces presented on this page employ galvanic isolation of the transceiver from PC computer. Audio paths are separated by transformers, optocouplers serve to separate the digital paths (PTT and RTTY keying).

Independence Missouri Police Scanner Page - Independence Missouri Police Scanner, live & recorded audio broadcasts.

Frequency Guide Victoria - A site for every scanner enthusiast but especially for people living or visiting the lower Vancouver Island Area and Victoria B.C. Canada. This page has pictures with aerial pictures.

ScanNewBedford.com - Welcome to scannewbedford.com. This site was built for people who would like to hear a live broadcast of New Bedford Massachusetts public services. There are also a few frequencies from other local towns such as Dartmouth, and Fairhaven being broadcasted on our live audio feed. The web site is free for everyone to use and pass along to another friend. Thank you and enjoy the Scan New Bedford Live Scanner Audio Broadcast of New Bedford`s Police, Fire, and EMS.

Radio Nepal - Radio Nepal airs broadcasts on mediumwave, shortwave and FM frequencies and news bulletins and music on the Internet via RealAudio.

Spectrum Lab  ^pop - DL4YHF's Audio Spectrum Analyser Spectrum Lab or Speclab started as a simple FFT program running under DOS a long time ago, but it is now a specialized audio analyzer, filter, frequency converter, hum filter, data logger and more. Can be used for MTHELL QRSS, DFCW, PSK, MSK, Castle

Koch Method CW Trainer - Based on the Koch Method as described by David G. Finley, N1IRZ, this software allows you to start out at the full speed you want to achieve by learning two letters and adding an additional letter once you reach 90% proficiency.

23 cm GaAs FET preamplifier - On 23cm the best way to obtain a good RX-sensitivity is to use a GaAs-FET in the front-end, since these devices show very low noise figures.

Receive only processing equipment - One of our most popular products, receiving preamplifiers are used for achieving top signal band performance in competition operating, low noise longwave reception, repeater applications into the UHF region, or lab use