Category Archives: CW and QRP

Articles related to CW and QRP (low-power) operating and equipment. Articles related to learning and using Morse Code are also included here.

The Elecraft K1

At least some of my interest in ham radio can be boiled down to my curiosity. How did they do it? How does it work? Why does it work? My college degree is in Computer Science, not Electrical Engineering, so I needed to start small and work my way up.

Radios do not need to be complicated to work. Like many of you, I imagine, I built a crystal radio and listened to AM broadcasts as a child. It seemed mysterious at the time (and still does, to a degree) that this simple collection of parts: a coil of wire that I sanded and tapped to tune, a small “diode” (whatever that was), and some earphones could take radio waves from the air and create sounds.

One of the reasons I became a ham was to learn a little more about how radios work. I think that’s why I gravitated to QRP stuff so early in my adventure. The radios were small and simple (at least compared to the big Icom I had on my desk), and yet they were “complete” transceivers. As a kid I would take apart anything I could find to see how it worked. (My survival probably depended on my being able to put things back together; I was relentless!) These small radios seemed like a gateway to learning.

Back in the early 1990s, Wayne Burdick, N6KR, designed a small, trail-friendly transceiver for 40m that was to become the NorCal (Northern California QRP club) 40. He completed this design by himself in three days! There wasn’t much to this radio. It had a couple of knobs, a BNC antenna connection, and two jacks for headphones and key. Later versions of the device produced by Wilderness Radio (called the NorCal 40A) included a keyer with memories, a boon to anybody working portably.

Wilderness Radio’s NorCal 40A photo from K7NIB (used without permission)

A destination of note for all things QRP and radio is the Chuck Adams, K7QO, website. In particular, I’ll point you to the catalog of YouTube videos Chuck has discussing many aspects of radio design. There are a couple of different builds for the NorCal 40A: one done Manhattan-style and another done on a PCB. You don’t need the kit to build the radio! Chuck shows you how to do-it-yourself.

http://www.k7qo.com/k7qo_youtubes.html

Me with Chuck Adams, K7QO, in 2006 at the Four Days in May convention in Fairborn, Ohio.

Alas, like so many things in our kit world, this radio is no longer in production. That is a shame for there is a whole book dedicated to teaching Electrical Engineering principles call “The Electronics of Radio” by David B. Rutledge, KN6EK, that uses the NorCal 40 throughout. The book is still available on Amazon.

https://www.amazon.com/dp/0521646456/

The book walks students through filters, transformers, transistor switches and amplifiers, oscillators, and mixers, all using the NorCal 40 as the example. As students build up the radio they learn how each piece works, and how it all works together. I recommend this book even if you never intend to build this radio.

Where this story picks up, though, is when Wayne Burdick and Erick Swartz, WA6HHQ) start the company Elecraft. Wayne’s NorCal 40 proved there was a market for radio kits, and radios with hot receivers and very-low power consumption. Their first offering was the K2, a multi-band radio. It was not unusual for DXpeditions to carry these Elecraft K2s to faraway places because of their exceptional performance. You can still buy K2 kits ($799.95).

Elecraft K2 transceiver. Photo credit B. Scott Andersen, NE1RD.

While the K2 is a wonderful radio, it isn’t exactly trail friendly. Here I am in San Francisco’s Golden Gate Park with my trusty K2. I was going to do some winter sprint contest of some kind, but the final transistor was shorted to the case and the radio wouldn’t work. I walked to a nearby Radio Shack® and bought enough tools to at least open up the radio and diagnose the problem. (I miss Radio Shack!)

Me at a picnic table in San Francisco’s Golden Gate Park in 2005.

A simplified version of this radio, the K1, came soon after the K2. The K1, unfortunately, is no longer in production. Some combination of lower demand and problems finding the through-hole parts needed by the kit doomed it. Nevertheless, the manuals for the radio are still available on the Elecraft website. You can download the complete K1 manual here: K1 MANUAL.

Elecraft K1. Photo credit B. Scott Andersen, NE1RD.

There are complete schematics for the radio and this wonderful block diagram illustrating how the radio components fit together.

K1 block diagram from the Elecraft manual. Used without permission.

I highly recommend fetching this gem if only to have the block diagram and the radio’s schematic handy. I printed out the schematic (just four pages, and really only two that are interesting) and carried them with me everywhere for a couple of years. I would occasionally take out these pages and follow along the signal path to see how Wayne Burdick and Eric Swartz did it. 

Me with Wayne Burdick (N6KR) in Dayton 2006.

The K1 manuals are free. Chuck Adams’ YouTube videos are free. There is a lot you can do to learn about how radios work by “taking apart” some of the best designs QRP radios have ever had. The K1 is such a radio.

Please take a moment and get that Elecraft manual for the K1 and give it a look. Skip past all the assembly steps and go straight to the back with the schematics and block diagrams.

I’ll go into the RockMite in my next article and walk through how the radio works.

Scott, NE1RD

Kit Building to the Next Level

Just a few days ago our soldering irons were hot and brows furrowed as we assembled our Morse Tutor Touch Keyer  kits from Steve Elliott, K1EL. NARS had done a good job of packaging the kits by supplying builders with printed instructions, and batteries. Nearly everyone had completed their kit in an hour or so.

Social events like this, where club members share the experience, are a nice way to spend an evening, but there is much more to the world of kit building. Ham radio provides one of the last bastions of building useful electronic devices at the component level. Other hobby and STEM efforts are confined to using completed boards for sensors, displays, and processors. Groups such as FIRST Robotics teams work with pre-packaged board solutions, their design process limited to selecting off-the-shelf devices and gluing them together with software. This is not to criticize such efforts. STEM groups and the whole Maker community do amazing things with this level of abstraction. Ham radio seems to be one of the only places left where our projects and understanding can be more granular.

There is a feeling almost impossible to convey when you use a radio that you constructed with your own hands. Even from a kit, where the circuit design, board layout, and part selections were done by others, there still exists a pride of ownership from the assembly. Each time the radio is used one thinks, “I made this.”

There are radios that are quite nice, but limited in utility, such as the RockMite. The original RockMite design was done by Small Wonder Labs run by Dave Benson, K1SWL. The basic radio was only $25 and consisted of a board, bag of parts, and a page of instructions. A “controls” package was also available for a few dollars supplying the potentiometer, switch, and other small parts necessary for completing the kit (in case your junk box was lacking). For a finished product you could add the fancy aluminum anodized case from the American Morse.

Kit Building - Rockmite

RockMite kit’s latest incarnation

If you wanted to spend a day, not a couple hours, this is an excellent choice for a kit. Ten years ago I organized a kit build for the Westord, Massachusetts club PART using this kit. To help insure new builders would have success I wrote a step-by-step instruction manual for this device. I’ve made it available here, but beware this is for a kit that is no longer available in that form.

RockMite-Assy-Manual

That day in 2008 the Westford club had ten builders working on a Saturday in a church basement. Eight of the radios were working by the end of the day with the others requiring a bit of tender loving care over a few more days. Proud of our accomplishment, I wrote an article for QRP Amateur Radio International’s quarterly magazine entitled “Ten Little RockMites.”

Dave Benson closed his Small Wonder Labs business a few years ago but not before handing the reins over to QRPme founder Rex Harper, W1REX, who has refreshed the lineup of RockMites and even added a few extras for them to the mix. I’ve bought one (or two), but I’ve not assembled them yet so I can’t speak to how well my old assembly instructions have aged. But, since the circuit is essentially the same, I suspect my old instructions, even after all these years, are still a good starting point—especially for new builders. The price is now $50 but the kit includes all the accessories, so it’s a pretty good deal ten years later! I would recommend anything from Rex. By the way, Rex Harper was inducted into the QRP Hall of Fame in 2010. Dave Benson has been in since 1999.

The RockMite is a CW-only radio that is crystal controlled. It supports only two frequencies. Granted, the frequencies are the QRP “watering holes” for each particular band, but still, two frequencies isn’t a lot. That said, one of the best ways to become comfortable with CW is to listen to signals off the air. Listening to signals from a radio you built is thrilling.

What if you’d like a little more from the radio you craft lovingly from your two hands? QRP kits qrpkits.com has several receiver, transmitter, and transceiver options. One of these kits is from a Steve Webber, KD1JV, design. The KD1JV Triband CW Transceiver comes in a nice case, has three bands (you choose which three), and outputs five Watts. This will set you back $225, but there is a lot of radio here to enjoy, both building and operating.

KD1JV Tri-Bander CW Transceiver

Alas, the radios I had in mind when I began writing this article have been discontinued. The Elecraft K1 and the KX1, both excellent kits and radios in their days, probably died more from a lack of through-hole part availability than from neglect.

Kit Building - K1Elecraft K1 built by NE1RD

Kit Building - KX1

Elecraft KX1 built by NE1RD

Elecraft, before they became the top-tier HF radio (assembled) maker was the premier radio kit supplier to the hobby. The K2, a very capable radio you can assemble yourself, supports CW and phone, bands 80-10m (with a 160m option), rig/computer control, and filtering. There is even a DSP option for the radio. This kit is an investment in both time and money. I have built two of these radios and each one took over forty hours to complete. But, when you’re done, you have a fully-functional radio that would compete with anything you could buy on the market.

Kit Building - K2

Elecraft K2 built by NE1RD

Unfortunately, or, perhaps, fortunately, radio technology has advanced significantly since the K2 was designed. Now you can get a DSP-based Icom 7300 transceiver with top-notch specs for under $1000. So, one wouldn’t build a radio like the K2 for performance alone. You’d build one for the joy of the experience. I must say that the time I spent building my Elecraft radios was some of the best memories I have in the hobby.

I encourage all of you to step up your game. Pick one of these larger kits. Spend a day, or a week, building something substantial. The sense of accomplishment you’ll have cannot be overstated.

I’ll be adding more articles about specific kits over the next year in hopes of coaxing members to step up their kit building game. Kit Building - K2

K2 close-up by NE1RD

Student Kit Build at World Academy

Aya KC1JEB, Tom AB1NS, Mike K1WVO, and Fred AB1OC recently hosted a Morse Tutor kit build for students at World Academy. World Academy was a HAB-3 School and the student kit build is one of several follow-on activities that we’ve been doing there.

Aya KC1JEB and Tom AB1NS Mentoring Student Kit Build
Aya KC1JEB and Tom AB1NS Mentoring Students at World Academy

We built a total of 16 kits over two sessions with the students at the school and had a lot of fun in the process!

Mike K1WVO Mentoring Students at World Academy Kit Build
Mike K1WVO Mentoring Students at World Academy

Thanks to the excellent mentoring by Aya, Tom, Mike, and their teacher Gisele, all of the kits have been completed and are working!

Gisele Mentoring Students at World Academy Kit Build
Gisele Mentoring Students at World Academy

In addition to mentoring the students, Gisele also built a kit of her own and got it working!

Fred AB1OC Mentoring Students at World Academy Kit Build
Fred AB1OC Mentoring Students at World Academy

Our next session with the students will be to help them learn the Morse Code and begin practicing with their kits. We are also planning a Morse Code competition using the kits similar to the ones we have done in the past.

This project has been great fun for all involved and we have provided the kits free of charge thanks to the support from our generous donors as part of our ongoing fundraising campaign.

Fred, AB1OC

Radio Amateurs Developing Skills Worldwide