out of band

124 links

Shortened dipole for 10 & 40m bands - A shorten Dual-Band Dipole with overall length of about 11 m. For this antenna traps are substituted by inductors, in order to cover the 10 & 40 m. Bands.
[ Hits: 4138 | Votes: 1 | Rating: 1 ]

W5GI Mystery Antenna ^pop - W5GI Mystery Antenna is a multi-band wire antenna that performs exceptionally well even though it confounds antenna modeling software. This antenna covers 80 to 6 meters with low feed point impedance and will work with most radios, with or without an antenna tuner. It is approximately 100 feet long, can handle the legal limit, and is easy and inexpensive to build. It is similar to a G5RV but a much better performer especially on 20 meters.
[ Hits: 139383 | Votes: 123 | Rating: 7.55 ]

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.
[ Hits: 7715 | Votes: 8 | Rating: 6.25 ]

Echelon-Log Beverages - About beverage antennas, Enhanced F/B Beverages, Bandwidth of Directivity, arrays. This article describes two phasing systems for Beverage antennas that improve directivity and cancel rearward signals. These systems use lossy elements and require minimal components to achieve broadband performance.
[ Hits: 1860 | Votes: 1 | Rating: 10 ]

Open Wire Feed Line a second look - Put up the longest dipole you can fit, feed it with open wire line, connect it to the balanced output of your tuner and poof! Instant multiband antenna. Is life really that simple?
[ Hits: 2680 | Votes: 8 | Rating: 6.69 ]

The G5RV Multiband Antenna - A French translation of the ARRL antenna compendium chapter about the G5RV Multi-band antenna,
[ Hits: 1638 | Votes: 0 | Rating: 0 ]

W4JOH Cobra Antenna - The original Cobra antenna, is a multiband 160 or 80 to 10 meter, designed by W4JOH is built using standard insulated wire of about 14 gauge and fed with 450 ohm ladder line down to the shack into a tuner.
[ Hits: 1710 | Votes: 1 | Rating: 10 ]
What make the carolina windom so good - The off-center fed CAROLINA WINDOM provides outstanding performance on all bands. This includes all the WARC bands, 30, 17, and 12 meters.
[ Hits: 6615 | Votes: 3 | Rating: 4.67 ]
Some plain facts about multiband vertical antennas - There is considerable confusion as to what exactly a multiband vertical antenna is. The confusion concerns the method of feed, how much mismatch one can expect, how many radials are required, how the particular antenna is built for multiband use, plus some other points.
[ Hits: 1910 | Votes: 1 | Rating: 7 ]
A Stealthy HF Coat Hanger Antenna - A multiband stealth antenna. Tuner is required. The antenna is made from a $15, 500 ft roll of black #14 insulated stranded wire, about 120 small black wire ties, and maybe 30 or so large black wire ties.
[ Hits: 7403 | Votes: 5 | Rating: 9.4 ]

Windom Antenna with 4:1 balun - The Windom is an Off-center wire multiband Antenna. The old version was fed just by a single-wire connected on 1/3 of antenna's overall length or with an open-line feeder (later versions). Here is another model with coaxial feeder, which is compatible with Solid States - 50 Ohm output transceivers .
[ Hits: 8027 | Votes: 9 | Rating: 6.89 ]

ZS6BKW variant of the G5RV - The ZS6BKW variant of the G5RV claims to offer multi-band coverage without the need for a tuner. This article looks at whether or not these claims are valid in a real life installation.
[ Hits: 7997 | Votes: 12 | Rating: 7.75 ]

Southern California Repeater and Remote Base Association - SCRRBA is a volunteer organization providing coordination of a number of heavily utilized amateur radio frequency bands in Southern California.
[ Hits: 741 | Votes: 0 | Rating: 0 ]

Russian VHF Trophy - For carrying out of bilateral QSOs on band of 2 meters, 70 and 23 centimeters all kinds of modulation. It is authorized to spend QSOs, using all kinds of passage: TROPO, ES, AURORA, MS, FAI, EME, IONO,
[ Hits: 652 | Votes: 0 | Rating: 0 ]

Sights and Sounds of Digital Signals - Preview the waterfall signature of various digital signals and listen to the sound of the digital modes. Learn about the bandwidth requirements and why a linear transmitter path is critical to successful and correct use of many modes on the amateur bands by W1HKJ
[ Hits: 1044 | Votes: 3 | Rating: 6.67 ]

Near-Real-Time F2-Layer Critical Frequency Map - This map can be used to determine the frequencies that will always be returned to the Earth. Transmitted frequencies higher than the indicated contours (which are given in MHz) may penetrate the ionosphere, resulting in lost power to space. The map shows the radio auroral zones as green bands near the northern and southern poles.
[ Hits: 5270 | Votes: 24 | Rating: 4.84 ]

Is HF propagation reciprocal - Some test circuits using the ACE-HF System Simulation & Visualization software, about reciprocal propagation on HF bands by NW7US
[ Hits: 523 | Votes: 1 | Rating: 7 ]

FilterCAD - A free computer aided design program to help users without special expertise in filter design to create filters using Linear Technology's monolithic filter ICs. With FilterCAD, you can design lowpass, highpass, bandpass and notch filters
[ Hits: 11767 | Votes: 28 | Rating: 5.03 ]

11 KW Linear amplifier by I0JX - Use 4CX10000D / 8171, RF output power of 11 KW in key-down carrier on all bands. Power was measured with a Bird 4712 wattmeter and a 25 KW slug
[ Hits: 24613 | Votes: 33 | Rating: 7.86 ]

Interdigital bandpass filter designer - Fill out the form to design a bandpass filter as described in the January 1985 issue of Ham Radio Magazine. These filters are generally limited to frequencies above 200 MHZ because their size is slightly longer than 1/4 wavelength
[ Hits: 1117 | Votes: 6 | Rating: 7.67 ]