Build a pair of QHAs, one for 2 meter and one for 70 cm, a diplexer is of course needed to connect both to the single antenna connector of a dualband radio

Antenna especially for frequencies in the range 2 - 5 GHz this design is very easy, practical, and, non critical

Ask anyone with a helix, it really is the best and simplest antenna for the job

a 23 cm 10-turn helix antenna and preamp for 222 MHz and up contest

This 50 ohm impedance antenna allows, when powered with 25-100W of RF in SSB, to reach satellites with Molniya orbit like AO-40 and AO-10

Quadrifilar helix antennas are also called fractional turn helix is very appealing to spacecraft applications

Building a 14 turn home-made helical antenna for 432/435mhz

The use of circular polarization at one end only gives a loss of about -3dB

a quadrifilar helix qfh antenna easily, from inexpensive materials, upvc plumbing pipe and rg-58u co-axial cable

2.4 GHz antenna design ideal for amateur satellite communications

Broad bandwidth in the 2.425GHz band

Software for calculator helix antenna

Construct a helical antenna for satcom listening, 240-270 mhz

Here is a page with images of a 3-turn helicoid that was built for a reception system in the 1690 MHz band

Helicals can be made with only household parts, a hot glue gun and a soldering iron

A helical antenna is an antenna consisting of one or more conducting wires wound in the form of a helix

S-band Helical Antenna by JH1CMP

Helical antennas have long been popular in applications from VHF to microwaves

design frequency mhz, number of turns, turn spacing, wavelengths

Build a pvc helix for a 'too high' frequency redetermine the center frequency 2430 mhz is approximately 67% of 3620 mhz

Sophisticated Helix Antenna Design,with matching Coax to 50 Ω

Cm helix, satnogs, v4, cm frequency: 434 mhz, cm wavelength: 691 mm, cm c=299792458 m/s, cm radius = 110 mm, cm turns: 8

Helix antenna diametro 4 mm- 6 spre su diametro di 40 mm con spire distanziate tra loro di 25 mm

Reflector Loop Dia: 10.66" The reflector is positioned 0.375" ahead of the start point of the first helix turn, first 4 Turns: 10.32", Next 7 Turns: 8.68", Last 12 Turns: 8.40

an antenna for receiving the AO-27 downlink at 436.800 +/- doppler, it is built with right hand circular polarization, and the gain is supposed to be in the neighborhood of 3 DB

I had always wanted to try and receive a signal from a satellite using my scanner

The quadrifilar helical antenna, it ideal for a number of uses. satellite reception and transmission may be number one among them

The axial-mode helix antenna, is probably the most widely used circularly-polarized antenna, either in space or on the ground

Helix for satellite uplink a 12-turn helix for about an 8' 2-1/2m

W0FMS javaScript axial-mode helix antenna calculator