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An inverted U wire antenna for 200 meters and down

The Walnut Tower antenna project

Interesting project to remotely control, using a servo control circuit, a common commercial antenna tuner by N30X

Build the PAC-12 Antenna a multi-band portable vertical designed by KA5DVS, here's an award-winning, easy-to-homebrew, multi-band portable vertical antenna designed by long-time antenna aficionado James Bennett, KA5DVS. He's documented the design and construction plans for a portable antenna

This is a combination center and top loaded multiband antenna by Mark D. Lowell, N1LO PDF File

Pictures of 2.4 Ghz antennas, JN1GKZ S-band homemade antennas

The 80-meter loop antenna, measuring 86 meters (282 feet) of wire, effectively operates across 8 HF bands from 80 through 10 meters, despite its length being a compromise for specific bands. This design prioritizes a "low enough" SWR across multiple bands, aiming for lower SWR values on higher frequencies due to increased feedline losses. A 200-ohm feedpoint impedance provides a workable SWR on every band, with feedpoint impedances ranging from 100 ohms for lower bands to 300 ohms for higher bands. Radiation patterns for the 80-meter loop, mounted at 15 meters high, show a maximum gain of 7.6 dBi at a 90-degree takeoff angle on 80 meters, and up to 12.9 dBi at a 10-degree takeoff angle on 12 meters. This configuration supports regional contacts on 80 meters and provides good DX performance on higher bands. Practical construction notes emphasize using robust supports like trees, ensuring wire slack with _egg insulators_ for wind resilience, and employing an oversized 2 kW 4:1 _balun_ to safely handle higher SWR conditions, even with 100W transceivers. Feedline losses are minimized using _LMR-400_ coax or ladder line, with power transfer efficiency between 80% and 95%. Antenna simulations were performed using _xnec2c_, and the provided NEC file is compatible with other NEC2 derivatives. The antenna is tunable on 6 of 8 bands with an internal ATU and all 8 bands with an external autotuner like the LDG AT-200 Pro.

This homebrew legal-limit antenna tuner is based on the famous "Ultimate Transmatch" introduced by the late Lew McCoy, W1ICP. The Ultimate Transmatch was described in the "Beginner and Novice" section of the July 1970 QST (Page 24).

Calculates resonant frequency of a loop antenna, correcting for distributed capacitance.

A dual-bander for 80M and 40m. An Extended Double Zepp (EDZ) is a 5/4 wavelength center-fed dipole. This article will introduce the Half-Extended Double Zepp (HEDZ) which has characteristics that a lot of amateur radio operators should find quite interesting

Article with detailed pictures of an endfeed antennna for 20 and 30 meter band

A portable antenna for mode B and J satellites

DIY Basic Electronic Theory, Basic Antenna Theory with Antennas built from common materials. What does SWR really mean. Baluns from transmission line.

Simple and cheap antenna for 40/80 meter band in Italian

This drawing shows a simple 10 meter wire J-pole antenna designed for 28.4 MHz. It is a vertical, end-fed Zepp-style antenna made from common materials and intended for easy home construction. The main radiating element is a straight length of stranded copper wire, either 14 or 18 gauge, cut to about 16.5 feet. At the top, the wire is supported by an insulator, allowing the antenna to be hoisted vertically. The matching section is made from 450-ohm ladder line, approximately 7 feet 9.5 inches long, and shorted at the bottom. This matching stub transforms the impedance so the antenna can be fed with coaxial cable. The feed point is tapped about 6 inches above the bottom of the stub, with the shield and center conductor connected at the proper points. A choke balun is formed with five turns of RG-58 coax in a 4-inch diameter loop to help reduce unwanted RF on the feed line. The drawing notes that this antenna has about 0 dBd gain, similar to a dipole, but offers an omnidirectional pattern and low-angle radiation when installed high. Its main advantage is practical performance, simple construction, and effective coverage for 10 meter operation.

This Antenna is not really practical for AO-40 reception, but horn antennas have a number of qualities useful in microwave antenna testing and noise figure measurements.

Constructing and designing full size, single band stacked yagi antenna arrays

A QRP antenna tuner for 20 meters band

This rugged antenna, an omnidirectional collinear, is capable of surviving harsh environments. It's a good choice for repeater installations and can be top, or side mounted to the tower by WA6SVT

An interesting article about homebrewing antenna traps for multiband antennas by VE3GK

A detailed drawing of a VHF UHF Log periodic antenna by VA2PHI

Plans, photos, electrical and mechanical design for this HF Log periodic antenna.

A few hours of fun with PVC and wire and you have got yourself a respectable road radiator. The antenna consists of little more than some PVC pipe topped by a RadioShack replacement whip antenna and a couple of coils made from a small roll of #14 house wire.

The multi-band trapped dipole is resonant on approx 3.7, 7, 14, 24 7 28.5 Mhz. The overall top length needs to be approximately 32.9 Meters

How to select an antenna for scanning. This is a Readers Digest version of antennas, meant to give new users some idea of the different antennas and their good and bad points.

One is an EFHWA for 20-40 meters, and the other is a matching unit for the antenna by n0lx

Even if using a tuner this multiband antenna will let you operate from 160 to 10 meters. If you could only put up one antenna, this would be it. Project by N0KHQ.

This antenna is intended as a simple, inexpensive solution for the newcomer to experiment across the 40m band (7.0-7.2MHz) when only restricted space is available

Base, mobile marine and cb antennas

Article designed to answer basic questions about antennas

Guide to calculate effective gain of antennas

Concentric Open Loop Antenna Fed Off-Centre similar to the cobwebb antenna but resonating on 20-17-15-10 meters band

80m to 23cm beam antennas, oscar antennas, and antenna rotors

Sardine Can Antenna. is a BiQuad or Bi circle - wire length each side (8 x 1/4 waves ) 31 mm

The finest in VHF/UHF antennas for Amateur and Commercial Applications. Antennas and Repeater Controller Accessories includes Rutland Arrays.

Article by Ed WE6W on a double bazooka antenna

Moxon antenna for 50 MHz, The Moxon rectangle is a quite broad-band antenna, but it is not quite broad enough to cover the entire band.

2el 40Ft front to back spacing 80 meters Quad antenna

40 meters band Delta loop antenna plan that is vertically polarised

What is the best balcony antenna? what antenna would you recommend for use on typical hotel balcony? Read some answers here

Antenna Tuner operation, correct way to tune an antenna.

The resource provides detailed information about a five-band indoor magnetic loop antenna designed for amateur radio operators. This antenna is capable of operating on the 20, 17, 15, 12, and 10 meter bands, making it a versatile choice for various HF communications. Constructed from a single 3-meter length of 22 mm copper tube, the design emphasizes compactness and efficiency, which is particularly beneficial for operators with limited space. The page includes insights into the construction process, tuning, and operational tips, catering to both novice and experienced users. In addition to the technical specifications, the resource also discusses the advantages of using a magnetic loop antenna indoors, such as reduced interference and improved performance in urban environments. It serves as a practical guide for those interested in building their own antenna, offering a straightforward approach to antenna design and construction. Overall, this resource is a valuable addition to the toolkit of amateur radio enthusiasts looking to enhance their station with an effective indoor antenna solution.

HF VHF/UHF yagi and quad antennas, towers and headphones manufactured in holland

Antenna for GSM, CB, marine, VHF/UHF, HAM and high frequency 1,9/2,4GHz

The PringlesCantenna is an ultracheap Yagi-type directional antenna that can be built for under $10. The original Pringles Yagi was designed by Andrew Clap.

This antenna modification is for the IEEE 802.11b networking protocol that operates at 2.4 GHz. It can be scaled easily to the 5 GHz frequency used by IEEE 802.11a by simply scaling the dimensions on the feed can and the excitation antenna to 2.4/5 = 48% of the dimensions shown above.

Coaxial Cable Dipole for 30 meters band by I2NDT with detailed pictures of his dipole antenna setup.

Arrl document about invisible antennas and indoor systems. It is important to consider that few compromise antennas are capable of delivering the performance one can expect from the full-size variety. But the patient and skillful operator can often do as well as some fellows who are equipped with high power and full-size antennas. The "cliff-dweller" may not be able to "bore a hole" in the band as often, and as easily, but DX can be worked successfully when band conditions are suitable.

Some practical indoor antennas that can be built by anyone

How to make a simple but effective Slim Jim antenna. It includes a calculator to work out all the mesurements for the frequency you require.