frequency 453.850

Another Approach to Active Antennas - Active antenna with a frequency response that is flat from 5kHz to over 30MHz

Ham Bands - Simplified U.S. frequency allocations table by K8ZT

Arizona Spectrum Management Association - This is the site for the Arizona Spectrum Management Association. This group is a frequency coordination group for the Arizona and the Tri-State Area

Microset - Power supplies, rf power amplifiers, dummy loads, frequency counters, repeaters antennas manufacturer based in Italy

Tecom - Tecom industries product line encompasses a wide range of highly sensitive active and passive antennas for use in airborne and ground applications, providing complete coverage of the 20 MHz to 40 GHz frequency range.

LCD Digital Dial DDS VFO - N3ZI KITS: Low Cost Frequency Counter and DDS-VFO kits

Satellite Frequency List - List of satellite frequencies from HT to VHF and UHF

AMSAT : Satellite Operating Frequencies - A comprehensive list of Ham Radio satellite frequency usage listed in order of frequency

MFSK16 - An MFSKMulti-Frequency Shift keying DX Mode. A new weak signal DX mode for Radio Amateurs, employing M-ary FSK, phase continous tones and convolutional coded FEC.

WSPRnet Weak Signal Propagation Reporter Network - A group of amateur radio operators using K1JT's MEPT_JT digital mode to probe radio frequency propagation conditions using very low power transmissions. Computer sent/received Morse signals received by amateurs and collected on an online database.

PorkControl for Yaesu FT-817ND - PorkControl is a Java-based software controller for the Yaesu FT-817ND (and older FT-817) HAM transceiver. It is currently in beta and released under the GNU GPL v2 on Windows, Linux and MAC OSX. PorkControl is used to control frequency and other features without using the fiddly controls on the unit itself. It also supports automatic radio control to access repeaters based on the UK Repeater List.

Yaesu 857 and 897 Extending frequency coverage - How to extend frequency coverage for yeasu FT 857 and 897 in italian by HB9TQF

Suomen taajuuslista 2000 - DB Frequency Site From Finland. In Finnish

LCD Digital Dial DDS VFO - Low Cost frequency counters and DDS VFO's for QRP and Vintage Radio's. LCD Digital Display, Frequency Counter or DDS VFO

Microwave Antenna Design Calculator - Available to run on all major operating systems, this free calculator provides quick estimation of antenna size required for a given gain and frequency.

SimJT - SimJT is a simulation program. It generates audio-frequency JT65 and CW signals in a background of gaussian white noise, with user-specified signal-to-noise ratio.

QSO Clock - little program for those that can never find a pencil when we hear the DX station calling CQ on the frequency on which we're tuned up.

Legendary microphones for ham radio - Graph of the frequency response of some of the legendary microphones favoured by radio hams

Resonant Frequency Calculator - This web based application will compute circuit values required for an L-C circuit to resonate at given frequency. Also it will compute the resonant frequency if given values for L and C.

Universal frequency counter & voltage meter - to be used with QRP transceivers

Frequency Locked Loop VFO for HF - A device which joins in a single microprocessor a digital programmable frequency meter and a control logic capable to lock a manually tuned VFO to its actual frequency by IK3OIL

Beware: RF Safety Considerations! - RF Safety reource page with links and more documentation on radio frequency safety

FCC OET -- Radio Frequency Safety - FCC Policy on Human Exposure to Radiofrequency Electromagnetic Fields

Noise tutorials - Noise foundamentals. Radio frequency interference noise.

Calculating the Received RF Noise Power - Voacap, high-frequency ionospheric communications analysis and prediction