g4egh

The oscilloscope.

What is an oscilloscope? The oscilloscope is a very useful piece of test equipment. It is a measuring device (if you paid many thousands of pounds for it), giving accurate measurements to a high degree. It is also an indicating device, (with a more modest budget) giving a good indication (with reasonable accuracy) as toContinue reading “The oscilloscope.”

A Bluebell Hill Radio Society project, and construction competition.

This article describes the construction of a medium wave amplitude modulation 7 transistor receiver. It is built from a kit of parts, sourced from ebay, where delivery from WITHIN the UK should be less than £10. The kit itself is of Chinese origin, and with a Chinese set of instructions, much frustration will be had,Continue reading “A Bluebell Hill Radio Society project, and construction competition.”

Dummy loads.

What are they, and what are they for? A dummy load takes the place of an antenna. It takes the transmitter power, and converts it to heat. Transmitters that are unable to output the power they have generated tend to suffer damage. When transmitter output stages used valves, they would withstand a “bad load” situationContinue reading “Dummy loads.”

DMR and hotspots

What is DMR? DMR “Digital Mobile Radio”. This description applies to the system designed by Motorola. Such a description could of course apply to the Yaesu Fusion system, or the Icom D-Star system, as all of these are digital systems, and all can have a mobile implementation. And there are others… As such the commerciallyContinue reading “DMR and hotspots”

DMR Radio programming guide

DMR Programming guide. This programming guide is aimed at giving the necessary understanding so that anyone can programme a DMR radio. It does not contain any screenshots, because although that would be very useful if you had the same radio as the author, it will almost certainly confuse if you don’t… First, a brief overviewContinue reading “DMR Radio programming guide”

Stubs

Stub… Your toe, maybe, out pounding the pavement? Or maybe it has something to do with radio? At these difficult times, finding something useful to do can be quite challenging. Not the least of reasons being the fact that you can’t get to a radio rally and get a few odds and ends for theContinue reading “Stubs”

Bluebell Loop Antenna

Greetings Everyone, Guess I finally “nailed” it. I built a couple of the mark two varieties, and not only do they work well, they also have survived a “drop test”, as they are a lot more robust! They are also smaller… This project is for a 2 metre “magnetic” loop. It works very well forContinue reading “Bluebell Loop Antenna”