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QHA Quadrifilar Helix Antenna


QHA Quadrifilar Helix Antenna

La QHA nasce come antenna per rx dei satelliti polari NOAA, METEOR

post 10 Jul 2024


Helix Antennas Links

34



Helix 435mhz uhf
It's actually 9.25 turns, including the quarter-turn impedance transformation to get a 50 ohm feed

Helix antenna design and construction details
Design frequency MHz, Number of turns, Turn spacing, wavelengths

Helix antenne
We decided to put it to the test and build a PVC helix for a 'too high' frequency. Then we wanted to redetermine the center frequency. 2430 MHz is approximately 67% of 3620 MHz. So that will be the design frequency that we give to HelixCalc


Linear-loaded-short-dipole-21mhz

Linear loaded short dipole 21Mhz For my amateur radio activities on the HF bands I only have a 3.6 m wide balcony available for antennas. After some study I decided to experiment with a shortened dipole for the 15 m band

Rx antennas 4Square Rx Vertical Array

Rx antennas 4Square Rx Vertical Array My frequency design of 1.825 MHz a 90 degrees line would be 33,70 metersinstead of the previously calculated 33,27 m

A simple SWR Meter is to be used at HF

A simple SWR Meter is to be used at HF An SWR meter provides information about how well matched is your antenna with the transmitter and how well power is being radiated