Dave Richards AA7EE

An Inline RF Step Attenuator for QRPp Work

I don’t need to explain the attraction of low power operation; if you’re reading this, the chances are that you are already a convert. I’ve been operating with low power ever since first being licensed in the UK in the late 70’s as G8RYQ, and then G4IFA. One of my first rigs was a homebrew […]

The GM3OXX “Oxo” Transmitter

As well as the small stash of finished projects that grace my living space, I also have two small boxes containing various boards. Some of them are boards from part-finished projects that didn’t work. For whatever reason, I ran out of steam and, instead of troubleshooting them, put them carefully into a small box along […]

Ugly Construction!

Here’s a little project I put together on a whim about 18 months ago. It was my tribute to the unlicensed (i.e. pirate) beacon cluster around 4096 KHz. There were several of them operating in full force, with powers ranging from around 100mW to a watt or so a few years ago. Their heyday was […]

Modifying the Tut 80 for Varactor Tuning and More Power

Back in 2009/2010 the Arizona QRP Scorpions released a little kit designed by Dan N7VE, called the Fort Tuthill 80. It was a QRP CW transceiver, with a direct conversion receiver and a transmitter capable of putting out about 3W. It caught my imagination, and I just had to build it. I have never had […]

The NM0S QRPoMeter

Some years ago, I purchased and assembled an Oak Hills Research WM-2 QRP Wattmeter from Milestone Technologies. As far as QRP wattmeter kits go, it was something of a classic at the time, and as such, I wanted one. I’m glad I made this purchase, as they are no longer available – at least, in […]

Testing Out Different Headsets with a Crystal Set and Assembling a Sound-Powered Headset

Before building Jim W4LF’s Hobbydyne™ crystal set, I put together an impedance matchbox, for matching the detector diode to a variety of different headsets and earphones, so that I could determine the best ones to use. The world of serious crystal set listening was new to me, so I did some reading up. To give […]

A Crystal Set Impedance Matchbox

Growing up as the youngest of 4 boys, I was well positioned to receive all the hand-me-downs. Although that might sound as if I just ended up with second-rate stuff, that was not the case at all. I inherited a lot of great things from my older brothers. I couldn’t have cared less that they’d […]

A Little WSPR Beacon (Aren’t They All Little?)

I first tried WSPR out in 2009, with a Signalink USB interface attached to my FT-817 and PC. For anyone interested in QRP and QRPp, the process of being able to decode a signal that is up to about 34dB below the noise level is quite fascinating. Morse code, sent by way of CW, engages […]

Another HiFER Beacon

I haven’t been building much at all, for quite a long time now. However, the urge occasionally returns. When it does, it’s wonderful to have a small stash of parts on hand, so I can pull the soldering iron out and start building before the desire dissipates. I’ve been interested in beacons for a while, […]

A Passive Tunable HF Preselector

When I built the VE7BPO DC Receiver Mainframe recently, it wasn’t intended to end up as a final finished project. The intention was more to have it as part of an experimental platform. The little box that contains the DBM, diplexer, and AF amplifier that make up the mainframe will most likely stay largely the […]

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