Small Transmitting Loops (STL) are loops of less than about 0.1λ in diameter or about 0.3λ in circumference. Below these limits, the current around the loop is almost uniform and this permits a simplified analysis.
STL are commonly known by Hams as “magnetic loops”, but that term is rarely used in recognised antenna text books.
The efficiency and free space gain of a circular STL can be easily estimated by calculation from simple measurements. Continue reading Efficiency and gain of Small Transmitting Loops (STL)
At (Bertelsmeier & Magnin 1992) formulas are given for calculating G/T from Sun/ColdSky Y factor in several Ham bands, and solar flux at 10.7cm. Continue reading DJ9BV & F6HYE G/T formula
DJ3JJ wrote up some interesting experiments with Yagis for 432 EME (Haefner 2010). Continue reading DJ3JJ’s 432MHz EME Yagi article in Dubus 1/2010
EMECalc v9.09 was opened, a model for 1296MHz created, and the “get IPS data” button pressed.
The report shows solar flux at 1296MHz to be 106SFU. Continue reading EMECalc v9.09 reconciliation issue
K5SO published an article in which he reported measurements of Sun noise rise over cold sky for K5SO, W2UHI and VK7MO.
Above is his graphical summary of the measurements. Continue reading Mining K5SO’s measurements of Sun noise
This article explains how to measure G/T using the Sun. Continue reading Measuring G/T
EMRCalc v9.09 contains a facility to fetch a current report of quiet solar flux from an online source.
Above is a sample report. Continue reading Checkout of EMRCalc quiet solar flux report
A correspondent asked if it was possible to calculate the link budget for an JT65 EME path using the G/T worksheet at (Duffy 2014). Continue reading EME path calculation based on G/T
For those who may have used or want to use my G/T spreadsheet tool I have discovered a defect in one cell’s formula. Continue reading G/T spreadsheet update (v1.09)
I was chatting on the weekend with a new ham who was inspired by an article in Amateur Radio to build an OCF dipole using galvanised fence wire.
I have not seen the article, but he recalled that it recommended single core 1.25mm galvanised wire as quite suited to the task of an 80m OCF dipole. The wire consists of a mild steel core with a thin layer of zinc. Continue reading Galvanised steel wire OCF dipole