random length

TX Four Square Antenna - A 220-ft tower that has five catenary lines, each about 500 feet long. Four of these lines, running NE, SE, SW, and NW support four 1/4-wavelength wire verticals used in a 160-meter four-square antenna.

19 elements Low Temperature 144MHz LFA Yagi Priority listing - This antenna has been deisgned using the very latest PSO techniques available today. There is simply no other 2m antenna of this boom length with better Sly Temperature or G/T figures.

An Inexpensive Vertical Antenna for 2m - This antenna is constructed from RG58 coax and a length of 1.5 m PVC pipe

Bobtail dipole - Bobtails are vertical arrays that look like the letter "E" turned 90° clockwise onto its tails. They have 3 quarter wave vertical elements and are one wavelength long. The Half Square is a shortened Bobtail- it has 2 quarter wave vertical elements and is a half wave long.

A 4:1 Air-wound Balun - 40mm diameter grey PVC pipe with a length of 9.5cm

Delta Loop antenna - This DeltaLoop antenna has a length of 125 meters, divided into three sides of 40, 42 and 43 meters.

All About Ham Radio Ladderline - Ladder Line Myths, Line Types, Spacing and Impedance, Length by KV5R

Adjusting HF Antenna Lengths  ^updated - Find out how much to adjust the length of a quarter wave whip or a half wave dipole rather than the outright cut-and-try method.

G4FON Magnetic Loop Antenna - A simple multi-band magnetic loop antenna designed for 20, 30 and 40 metres, but by changing the overall length of the wire coverage of other bands is feasible

A 5/8 wavelength mobile whip - by Lou Blasco VK3ALB

Dual Band Quad Antenna - 4elements 50Mhz and 70Mhz dual band OWA Quad Antenna with a 2.7 metre length boom by G0KSC

Double Quad For VHF UHF - Double quad wire antenna for the 2m and 70cm band. Each of the two squares is the size of a wavelength by DF7DJ

Five eighths wavelength vertical antenna - The basics of a five eigths wavelength vertical antenna, a form of RF antenna widely used for mobile radio communications applications

VSWR Reactive Power - Many antennas and antenna designers neglect the true cause of loss. The major problem using short antennas is the reactance, not the length

Bootstrap coax traps for antennas - Analysis of an antenna trap where a coil is formed of a length of coax cable, the outer conductor of one coax end is tied to the inner conductor of the other coax end, and the remaining connections form the terminals for the trap.

70cms and 2m Dual Band Aerial - A prototype antenna built using a single approx. 2.3 meter length of 4mm stainless steel wire

K0WA 40 meter verticle - The antenna is comprised of three lengths of 12 foot aluminum which telescope together.

Long wire antenna random wire - About longwire antennas, technically to be a true longwire an antenna needs to be at least one wavelength long, but common use of the term by Hams is for any random wire length that is end fed.

Random Wires revisited - Article on random wire antennas by KH6JRM

2-El Portable Yagi for 10-20 mt  ^updated - This Yagi has a constant element-distance of 1,50 m. You must only correct the lengths of the elements for QSY, see table down. For the bands 10 m and 12 m the Yagi is working as a reflector-radiator-Yagi, for 15 m and 17 m as a beam with radiator and director.

Roger G3XBM's Amateur Radio Blog - Simple QRP projects, 10m, 6m, WSPR beaconing, sub-9kHz and other random stuff

KE2YK's Random Oscillations - Amateur radio news, events and other electronic stuff by KE2YK

EME Low Noise 14 elements Yagi - Ideal for EME with a Sky Temperature never seen at this boom length. Amazing pattern and flat SWR. 50 Ohm with no matching required.

Radio Works - RadioWORKS is a tool for calculating various items related to radio waves and radio wave propagation. Get detailed information about a frequency, such as the free-space wavelength, band classification, propagation methods, common transmitter configurations, etc. Calculate antenna lengths or frequencies. View a 3D coverage map by providing a latitude / longitude coordinate and transmitter height.

CW Trainer for Linux - Easy to use CW Trainer for Linux. Adaptable for both the Koch and Farnsworth method of learning CW. Makes random tests or can read text from a file