40 metre

A portable 10/20/40 mt vertical antenna  ^pop - A portable vertical antenna for 10 to 40 meters, designed for mobile operations can be used in a car as seen in pictures. A modified version for 20 and 40 meters is described too.

A 30/40 meters band vertical anetnna - A shortened 30/40 meters band vertical antenna in italian

40 meter double bazooka antenna - A double bazooka antenna plan for the cw portion of the 40 meter band by k0ru

3 Elements on 40 Meters - The inverted "U" 3 elements on 40 meters by ik2egl

Shortened vertical antenna for 7 Mhz - A simple drawing of a shortened antenna for 40 meters by using a PVC tube

Trapped dipole for 80 and 40 m - This article explores a theoretical model for the losses of an 80m / 40m trapped inverted V dipole antenna system using a bootstrap coax trap, but does not examine the pattern of the antenna.

The ZigZag Vertical Beam - Six metre enthusiasts might like to experiment with this ‘Zig-Zag’ four-element vertical for lofts. Brian Williams, GW0GHF

OH7SV Windom baluns - Windom baluns for kilowatt range made with two ferrite toroidal cores amidon ft-140-61 and another schema with two ferrite rods

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.

Multiband HF antenna - A multiband hf antenna for restricted spaces covering 80 40 20 15 meters Based on the VK2ERG shortened 80M dipole

Magnetic loop for 40 meters - Mag Loop aerial for 40mtrs. Diameter is 3 Mtrs. Rotator and tuning with pictures.

JJ6 Antenna - Beam antenna for 14-18-21-24-28-50 Mhz by G4ZU in french

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.

Musings on the Miracle Whip design - A modified design of this popular portable antenna The whip described here will tune up to a respectable SWR on 40 metres and up.

A Q&D Multiband Antenna - A brick, some PVC tubing and a few other common hardware store items can be transformed into an effective Quick & Dirty RF-launcher—for less than $25! By Michael Atlas, N7FC

BiQuad Antenna for 144/440 - This is a vertically polarized Broadside and Collinear Array each Loop is a vertically polarized Broadside Array both the right and the left side of the Loop is a bent 1/2 wave dipole working 180 degrees out of phase with the other one and that gives you 4.15dbi of gain by KE4UYP

2400 MHz Helix Antenna - This antenna is easy to build and suitable for broadband work, satellite work and terrestrial work.

ZL1BPU Rotator Controller - A very simple controller circuit, with fairly smart performance! The ZL1BPU Rotator Controller has been designed as an add-on unit for the popular Kenpro KR-400 and Yaesu G-400 rotators. The controller consists of a small circuit board which fits inside the rotator control box (see picture).

Shortened antennas - Drawings of shortened antenna for indoor usage, using short pvc tubes for 2 , 20 and 40 Mhz by f1rfm

UKSMG sporadic-E competition - THE Six Metre event of the year The contest is open to all users of 50MHz, whether or not UKSMG members.

G4UCJ 6 meter report and recordings - Recent six meters report from UK with recording of some QSOs

Makidenki - Transvertes, AO-40 Convertes, FM-TV transmitters UHF loop antennas

Accute Micro - China supplier of ceramic bandpass filters in standard resonator sizes of 2~6mm , 8mm , 10mm and 12mm with freqency from 400Mhz~4Ghz and sections 2~10

40 Meters QRP AM/CW transmitter - VU2VWN project to homebrew a CW for 40 meters band

A single board no tuning 23 cm transverter - This transverter uses bandpass filtering with printed hair-pin filters. By KK7B