rf circuits

50 MHz Antennas by DF9CY (4 & 6 Element)  ^pop - Two well performing 50 MHz antennas designed with W7EL EZNEC along to many other antenna projects and related articles

Build A Tin Can WiFi Antenna - Build a tin can waveguide WiFi antenna in one hour. Then put it on a 18" inch direct tv dish. No coax signal loss. Use a USB device on antenna. Complete instructions to build this powerful wlan antenna

Romeo Fox Dx Group USA - Membership Info no cost to join

HF Hamtrader Nes - Trader net frequencies

The Amateur Radio Flea Market - Treffpunkt Amateurfunk (German)

SGC, Inc. - Manufacturer of HF transceivers, antenna couplers, antennas, RF Power amplifiers, portable antennas, speakers and other accessories for 28 years.

Signal Engineering - Signal Engineering technologically advanced antennas with modern design and construction technique. Up to date information about current line of high performance 10 and 11 meters antennas.

MARS Antennas - MARS, Israel's Antenna and RF System manufacturer, flat antennas for cellular, military broadband, multiband MF high power antenna

Nil-Jon Antennas - Performance Compact Antennas VHF/UHF mobile and base for ham, business, landmobile, police, fire, satellite, APRS, simplex, repeater, TV, FM, scanner or monitoring use.

Poly Phaser - Data, RF, video protectors coax combiner protectors, grounding Items

HD Communications - Rf Connectors,RF Amplifiers,RF Filters,HF cable and accesories. Tower hardware valves and tubes

Kiwa - Filters and performance upgrades for many receivers

Tigertronics, Inc. - Packet/telemetry modems, GPS tracking, sound card interfaces

Pacific Research Solutions - Repeater Controllers, Repeater Tone Panels, Telephone Interface, Remote Monitoring Systems, Process Control and TDS Monitors

US Frequency Allocation Chart - Colorfull radio frequency spectrum allocations in the US, in PDF Format

Current Aurora status - The Aurora in near real-time from Sweden

The Sunspot Cycle - Sunspot Numbers, The Butterfly Diagram, the Greenwich sunspot data and sunspot realted infos.

National Weather Service - Some little known facts about the NOAA Weather Radio system

CBC International CB Radio - "CB books, plans, and kits. Repairs, modifications, 10-Meter conversions, amplifiers, FM, unique high-performance accessories. Publishers of the classic ""Screwdriver Expert's"" Guide book."

RF Limited - CB and Ham Radio accessories

Radioman - Freeware dos VHF/UHF Logbook morse code facility, kenwood transceivers interface, moontracking, distance and bearing calculators by DF9CY but discontinued and unsupported

AREPS propagation programs - Collection of various propagation software by Space and Naval Warfare Systems Center, San Diego, Atmospheric Propagation Branch

RF prop  ^pop - RF propagation software

TH-D7 control program - This software allows you to control TH-D7 radio functions in real time, using a windows interface. This software will graph current activity of any 4mhz range, allowing the user to mouse click any active portion - automatically changing the radios frequency.

Gain receiver performance - Tips for those who wish to gain another level of performance from their receiver