JA7KPI Windom antenna for 40-80
- The total length of this antenna is 41m, height is about 11m, and diameter of element is 2mm.
JA7KPI modified this antenna originally used as Inverted-V type of 80m band Dipole.
Works on 40 - 80 meters band with acceptable swr.
Wire Antenna for 75 and 80 Meters
- This article is about a wire antenna that covers the entire 3.5 to 4.0 MHz band with an SWR below 2:1
consists of two coupled dipoles, one resonant at about 3.5 MHz and one resonant at about 4 MHz, resulting in the low SWR
Simple HF Baluns for 50/75 ohm coax
- Show diagrams, winding methods and tables of some 1:1 and 4:1 baluns for 1.8 - 30 MHz suitable for use up to 200W (400W peak) on systems using 50 or 75 ohm coaxial cable input where SWR should not exceed 1.6:1.
Vertical antenna for Vacation
- Vertical Vacation Antenna for 80, 40 and 20 Meter-Band, by Herbert OE3BMB
This antenna is a full size λ/4 for 20m and 40m band, and a shortened λ/4 for the 80m band.
Generally on the 40m band the SWR is under 1,6. In 80m and 20m band at the resonant frequency the SWR is about 1,1.
Matching Waves, VSWR at work
- When the radiation resistance (voltage to current ratio) of an antenna is the same value as the characteristic impedance of the transmission line (voltage to current ratio in the line), all of the electrical energy transmitted down the line is taken by the antenna and radiated into space in the form of a radio wave.
Yagi antenna Q Factor
- How you can calculate antenna Q factor for use in antenna quality evaluation instead of use of VSWR bandwidth.
10 m Aerial Matching Unit
- This simple matching unit will allow a 10 meters aerial to be used right across the 10m band without the need to physically adjust the elements, and offers a virtual 1:1 VSWR at 50 ohms impedance to the transmitter.
HB9FX Internet Remote Base JN37XH Hochwacht Zofingen Switzerland
- Tune and / or listen between 10kHz - 10GHz to professional Online-Receivers as Rhode & Schwarz EK070 or AEG E1900/3, Amateur-Radio-Transceivers, Web-SDR, Digital-Modes, Repeaters, EchoLink, APRS or control Antenna-Switch-Matrix, Antenna-Tuner, SWR & PWR- Control or Web-Cams.