I noticed a number of unfamiliar call signs appearing on the aprs.fi info page as stations located near mine, and some clearly corrupted format. These included VK2RR-1, VK2AW-1, VK2OM-9, VK2YGV9 to name just a few. Last update: 25th August, 2014, 7:45 PM
This article explores the radiation efficiency of KP4MD’s (Milazzo 2012) small transmitting loop (STL) using a set of NEC-4 models of the loop at varying heights above ‘average’ ground. Last update: 11th November, 2015, 4:56 PM
This article explores the radiation efficiency of a small transmitting loop (STL) using a set of NEC-4 models of a 3.14m perimeter loop on 7MHz at varying heights above ‘average’ ground. Last update: 28th February, 2017, 8:29 AM
Small transmitting loops (STL) are often recommended for use inside buildings, on balconies and even hand held, but are they EMR safe? Last update: 17th April, 2015, 7:07 AM
One of the feed arrangements used for small transmitting loops (STL) is the so-called gamma match, though it is questionable if these are quite the same as matches of the same name on a linear dipole. Last update: 17th April, 2015, 7:07 AM
The ‘net abounds with articles describing easy to build low cost small transmitting loops (STL). This article describes measurement of a STL for 4MHz using RG213 coaxial cable for the main loop and its tuning capacitance, and a smaller plain wire loop for transformation to 50Ω. Last update: 7th April, 2017, 9:10 AM
There are many calculators for design of small transmitting loops (STL). This article compares one quite old DOS one and a mature popular modern spreadsheet. Last update: 12th December, 2018, 11:14 AM
Off centre fed (OCF) dipoles are very popular with Hams on HF. Many claims are made for variations of the theme, but the essential common feature is that the offset feed point provides a feed point impedance that is not too unsuited to 50Ω coaxial feed line at the fundamental resonance of the dipole and … Continue reading OCF dipoles
Efficiency and gain of Small Transmitting Loops (STL) referred to an online calculator (Calculate small transmitting loop gain from bandwidth measurement) for estimating the efficiency and gain of an STL. This article documents an NEC-4 article of a 1m diameter tuned loop of 20mm diameter copper at 7MHz with a driving loop of approximately 0.2m … Continue reading Validation of loop efficiency calculator
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. (A stricter definition of 0.3λ in circumference could be argued.) These antennas are ascribed all sorts of magic properties, low … Continue reading The magic of small transmitting loops