What really determines the efficiency of an antenna?

Is it Standing Wave Ratio (SWR)? It is common knowledge that when an antenna has high SWR some of our transmitted power is wasted instead of being transmitted. But is this really true? The trouble with "common knowledge" is that it spreads without further scrutiny. "It must be true because that's what everybody thinks". But … Continue reading What really determines the efficiency of an antenna?

4:1 Balun or 4:1 Unun – how to choose?

Perhaps one of the greatest confusions in the hobby of ham radio is wrapped around the subject of baluns and ununs. What are they, where should they be used and what do they do? At Ham Radio Outside the Box several antennas that need a 4:1 impedance matching device have been described. Since I had … Continue reading 4:1 Balun or 4:1 Unun – how to choose?

A simple outside the box fix for a broken telescopic whip

"If it ain't broke, don't fix it" Or conversely, if it is "broke" you have two choices. Order a replacement from the other side of the planet, and wait for the slow boat from China to navigate thousand of nautical miles across the stormy waters of international seas. Or, alternatively, and my preferred solution, is … Continue reading A simple outside the box fix for a broken telescopic whip

Construction of the Simple Low Profile Multiband POTA Antenna

Following on from the previous post, there seems to be some interest in how the Simple, Low Profile, Multiband POTA antenna was actually built. Although the antenna is described as "simple", that term relates more to how it is deployed and its appearance than its actual construction. The construction does not involve any special tools … Continue reading Construction of the Simple Low Profile Multiband POTA Antenna

A Simple, Low Profile, Multiband Antenna for POTA

Sometimes it is necessary to set up for a POTA activation in an area where other park users like to go. In this situation we can either entertain distracting inquiries from people passing by who may just be curious about our activity, or blend into the environment and not be noticed. I prefer the latter. … Continue reading A Simple, Low Profile, Multiband Antenna for POTA

How many truly field expedient ham radios are available? Maybe only 2!

Only two? If you were to ask the military you might get a different answer. Indeed many hams actually use ex-military portable radios, such as the PRC series. Those radios are in a class of their own, but they are often heavy, designed to be carried into the field by fit, strong, young soldiers. But … Continue reading How many truly field expedient ham radios are available? Maybe only 2!

Does an antenna top hat really work?

Antenna "Top Hat" aka Capacitance Hat There are several ways to shorten a vertical whip antenna, for example, a loading coil, linear loading (folding back all or part of the radiating element) and one that has intrigued me for quite a while - a capacitance hat, also known as a top hat. A top hat … Continue reading Does an antenna top hat really work?

An Outside the Box version of the Delta Loop antenna

I have written about delta loop antennas before - notably in April 2023 in a post entitled "Delta Loopy Ideas". A few weeks ago I received an email from Alan WA3EKL who suggested I should take another look at delta loops and offered a lot of helpful advice, tips and suggestions for making this type … Continue reading An Outside the Box version of the Delta Loop antenna

An improved tank circuit EFHW coupler

About a month ago Ham Radio Outside the Box posted about "a third way" to match the high impedance at the feedpoint of an End-Fed Half-Wave antenna. A link to the original article is at the bottom of this post. A "30-minute special" was built to prove the concept actually works. It did work fine … Continue reading An improved tank circuit EFHW coupler