Category: QRP

Dabbling in Circuit Art: The LM386 Spider

Last month I built the DC40 receiver (and wrote a giant series on it: Part 1, Part 2, Part 3 and Part 4. And somewhat unofficially Here!) and at the same time, Hackaday.com posted their Circuit Sculpture contest. Would it be possible for me to combine projects, and submit the DC40 as a circuit sculpture of some …

Continue reading

QSX Update: January 2019

We know that Hans Summers of QRP Labs has been working hard on the QSX for many months. Hans unfortunately had to deal with some rather worrisome health issues. Those are handled now and he’s back in action, and work on the QSX is progressing steadily. On Wednesday 9, 2019 he did a presentation for …

Continue reading

KI7MNW’s Homebrew QRP Transceiver

Cameron Tribe, KI7MNW recently posted his homebrew QRP transceiver on the Amateur QRP Radio group on Facebook. It’s completely scratch built and borrows design elements from several sources including the BITX40. Follow all the way to the bottom for a picture gallery, schematics, and source articles. Tonight I finished my homebrew 40m QRP transceiver. I’ve …

Continue reading

Building a Direct Conversion Receiver: Part 4

We last left off with having built the Diode Ring Mixer portion of the DC40 direct conversion receiver that we started on in Part 1. As was discussed, the Diode Ring Mixer accepts input from two sources: The antenna (through a Band Pass Filter) and the VFO. Now it’s time to examine these two critical …

Continue reading

Building a Direct Conversion Receiver: Part 3

In the first installment, we talked about choosing a Direct Conversion receiver design to build and getting started with the most basic parts. Part 2 dove into Manhattan construction and building the amplification stages. For this third installment, we’re going to discuss the functions of the Diode Ring Mixer, Band Pass Filter, and VFO stages. …

Continue reading

Building QRP Labs Band Pass Filters: 3 Tips you should know!

QRP Labs Band Pass Filters are these wonderful little kits that largely take all the question of building a filter. They use a proven design, the kit includes the inductors and wires, and the build instructions are top notch.  One thing I love about the QRP Labs Band Pass (and Low Pass) filter kits is that …

Continue reading

QSX Update: Spectrum Analyzer!

For those of us anticipating the release of the QRP Labs QSX (which we talked about in A Previous Post), any news from Hans Summers, the owner of QRP Labs, is exciting. He posted an update over the weekend that will whet the appetite a bit. If you’re unfamiliar with what a spectrum analyzer does, …

Continue reading

Building a Direct Conversion Receiver: Part 2

In the first installment of this series, we discussed why we’re building a Direct Conversion receiver and talked about some basic ideas. In this installment, we explore what it takes to make the leap from a printed schematic to something physical that works. Follow along! Schematic Semantics The DC40 was originally designed by Ashhar Farhan …

Continue reading

Building a Direct Conversion Receiver: Part 1

QRP Labs VFO, bare PCB with just the audio amplifier stage and a power strip to the left side of the board.

In this series of posts I’m going to take you on a journey. We’re going to explore the Direct Conversion receiver together, and I’m going to show you every bit of the journey that I can. Let’s get started! Why build a Direct Conversion receiver? When I restarted in ham radio in December 2016, it …

Continue reading

L-Match Tuner Build for QRP Operation

In this post we’re going to build an L-Match tuner for your QRP wire antenna. But you might ask: Why do I need a box between a bit of wire and my transmitter? That’s a good question! Amateur radios are constructed in such a way that they have an impedance of 50 ohms. For portable use …

Continue reading