frequency counter

EH antennas and CFA antenna - Many antennas function because of common mode currents, rather than working in spite of them. Two popular examples are CFA and EH antennas. Another recent example, appearing in Antennex's compact antenna articles, is a thick stub "vertical" with no counterpoise.

Quarter Wave with radials - VHF quarter wave antenna mainly for scanner usage, The quarter wave antenna is an easily designed and constructed antenna for whatever frequency you want, although with the following design, you may to limit it to the VHF and UHF bands due to the physical size.

Multi-Elmac - THE MULTI-ELMAC AF-67 Trans-Citer is a ten-tube variable frequency or crystal controlled seven band transmitter.

The Northern Beacon - Beacons frequencies and location. This is the 1st edition of an enormous collection of Long-and Medium Frequency Beacons monitored in Norway

Pipo Communications - The highest-quality and most reliable Dual-Tone Multi frequency encoders.

K2RF Communications Products - K2RF is a manufacturer of radio frequency, audio, and video processing products including repeater link controllers, speech limiters, and RF equipment for the commercial, HAM, and amateur radio consumer.

Delta Technology - DELTA Technology is specialized in the lightning protection field, surge arresters, lightning counter.

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

Definition of frequency bands - Definition of radio frequency bands, hf vhf uhf etc.

The Shortwave Broadcast Bands - For convenience, the shortwave part of the radio-frequency spectrum is subdivided into bands. Each band has its own unique propagation characteristics

USCG Navigation Center DGPS - Differential Global Positioning Service (DGPS) is a land-based augmentation system that receives and processes signals from orbiting GPS satellites, calculates corrections from known positions and broadcasts these corrections via a Medium Frequency (MF) Transmitter to DGPS users in the Broadcast Site’s coverage area.

Frequencys for wefax - Where wefax transmission can be heard.

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.

Frekvenser.se Swedish frequency list - On of the best Swedish frequency lists, in swedish

Melbourne metro scan frequency guide - Police, fire, transport, ambulance and many more frequencies

S.A. Scanner Monitoring - Police, emergency services, fire and other useful frequency pages

J Pole calculator  ^pop - Enter the operating frequency and calculate dimensions of your jpole antenna

AC6LA MoxGen - MoxGen will show you the dimensions and generate an antenna model file for a 50 ohm Moxon Rectangle antenna, given the design frequency and wire size

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

RF and Microwate Power Amplifiers - RF and Microwave Power Amplifier and Transmitter Technologies, amplifierlinearity, efficiency and available RF power devices.

Coaxial Cable & Power Handling - This calculator can be used to estimate the attenuation (dB loss), power handling capability, and transmission efficiency for some of the more popular Wireless Communications and MIL Spec cables at the frequency of interest

50MHz frequency counter, V-meter - Circuit schematic PCB and photo documentation on building a 50 Mhz frequency counter

Direct Conversion HF Transceiver with DDS LO - Direct conversion HF radio with DDS frequency synthesizer is very interesting concept. OH7SV and OH2NLT are experimenting with such rig. Full stories will become available when project matures. Here we have some preview pictures and material.

6m High Pass TVI filter - Are you suffering from TVI? Then why not try this filter for size. It is a three-stage high-pass filter that blocks low-frequency 50MHz signals while letting through UHF TV.

iCOM PCR 1000 Web Resource Page - ICOM PCR 1000 user website with tips, manuals, hacks and frequency list for this no-interface radio receiver.