Amateur Radio Weekly is curated by Cale Mooth K4HCK. Sign up free to receive ham radio's most relevant news, projects, technology and events by e-mail each week at http://www.hamweekly.com.

…with Arduino.

My relationship with computers is a love-hate one. They are too complex and fragile to be reliable and always let you down when you most need them. But there is a miniature computer I really love: the Micro Controller Unit (a.k.a. MCU). They are simple and reliable, because they do one thing and they do it well. For us hobbyist the two most well known are Microchip Technologies’ PIC and Atmel’s AVR. I dabbled with PICs before, but they are a pain to program and require special hardware to do so. Enter Arduino. These guys from Italy took Atmel’s AVR chips and put them on a board with an easy to use USB interface and an integrated development environment, which uses a dialect of C. Weehee, could it get any better?

MCUs are just like Legos: add some sensors and an LCD and you have made yourself a weather station. Add some wheels and a motor and you created a robot. The possibilities are endless. But just like Legos my Arduino projects have been build and then taken apart for the next project. This is about to change now. My loop antenna needed a way to switch between the 7, 14 and 28 loop turns and it had to do so remotely. “Well, use relays” you would rightly say and those happen to be one of the easiest things to hook up to an Arduino. Let me show you.

Two wires for power and one control line (here hooked up to the Arduino input/output “pin” number seven) so simple enough. But it won’t do a thing until you tell the Arduino to do something, using a program. For writing such programs there are computer languages, and they are just that: languages. Learn how to interpret a language into your own and you’re good to go. It might scare you off, but then isn’t electronics a kind of language as well? Remember, I honestly can’t call myself a programmer, but with a guide book and some advice from the experts I can go a long way in making something exciting. Don’t believe me? Let’s start with the basics.

Arduino programs are made up of three blocks of code:

1 – a block to declare and define the things you need later
2 – a block to set up those things
3 – a block that does stuff with those things over and over and over again

Can you spot the three blocks in this example?

The first block features only one line: “int relayPin = 7;“. Let’s put that in plain English: we use pin 7 of the Arduino to connect the relay to, and instead of “pin 7” we now call it “relayPin”. And because “7” is an integer we also declare that.

Every pin on the Arduino board can be used to either get signals in or out, so that’s what we define in the setup block: set the pinMode of the relayPin to OUTPUT.

Since we set the relayPin as an output pin we can activate it and that is what happens in the loop block. First we write to the relayPin and make it active, or HIGH. Then we have a slight delay of 1000 milliseconds, after which we write to relayPin and make it inactive, or LOW. After another 1000 millisecond delay the whole sequence in the loop block starts all over again. After compiling and uploading the program to the Arduino the result looks like this….

It might not seem very useful to have an oscillating relay, so we need other ways to control it. I’ll cover that next time.

In the mean time, Arduinos are pretty cheap and together with a breadboard, a bunch of wires and some LEDs you can already start playing around. At Banggood.com you can get a bare Arduino Uno for US$3.99. This is a knock-off version, but they work equally well. A whole starter kit is only a little more, so it won’t break your bank.

On the internet there are tons of tutorials, YouTube videos and forums to help you with your first Arduino/MCU steps. I’m sure that after the initial steps MCUs won’t be so intimidating anymore. So, try it and have fun.

Hans "Fong" van den Boogert, BX2ABT, is a regular contributor to AmateurRadio.com and writes from Taiwan. Contact him at [email protected].

A recent posting to the Yahoo AWAGroup, reminded me of a wonderfully simple transmitter that would easily get anyone on-the-air for the Bruce Kelley '29 QSO Party coming up in December. The AWAGroup is largely composed of '29 builders and operators and is often the source of much good discussion related to these activities.

When builders first tackle a '29 style rig, eligible for the BK Party, the first thought is often about finding an affordable tube that might make the transmitter a 'legal' entry. A suggestion of tubes and their relative availability can be found here in one of my earlier blogs. Although some of the tubes may not be typical junk-box items, one that is often very readily available and inexpensive is the '27' or the '227' / UX-227.

The '27 was a popular audio tube used in receivers back in the 20's and can easily be pressed into service as a self-excited oscillator on HF. When properly adjusted, the '27 can produce up to 4W of RF, more than enough for you to join the '29 fun a make plenty of contacts over the dual-weekend event.

Scott, WA9WFA, has produced a great article describing the construction of a 1929 Hartley oscillator using the 27. There is no need to utilize period-appropriate parts, other than the vacuum tube itself. If you are pressed for building time or just want to get something on the air, there's no need to be overly concerned about construction aesthetics ... there's plenty of time for that later, and besides, the uglier ones often work and sound the best!

WA9WFA's 27-Tubed Hartley

Power supply requirements for the transmitter are pretty minimal and could even be an old receiver supply ... something that delivers 250-300 VDC at 35ma. An effective way to easily double the power of this transmitter is to add a second tube in parallel with the original one, providing your power supply can supply the extra current (~35ma) required. Although Scott's information describes an 80m Hartley, there is no reason why you could not wind a coil for 40 or for 160 and take advantage of any activity on those bands as well. Like most of these link-coupled outputs, you'll probably squeeze a little better efficiency from the circuit by adding a variable capacitor (~365pf) in series with the pick-up link and the hot-side of the coaxial feedline.

Nick, WA5BDU, wrote his description of building the 27 Hartley which can be found here. He also includes information on running the 2.5V filament from a 5V transformer.

WA5BDU's 27-Tubed Hartley

ABØCW uses two 27s in parallel for the oscillator section of his 1929 MOPA. Details of his interesting Hartley can be found here.

ABØCW's Parallel 27s

As further proof that you don't need a lot of power to have fun in the 1929 BK Party, here is the rig that Kevin, WB2QMY, used when we worked on 80m CW. His little TNT, just barely putting out 2W, made it all the way from New York!

WB2QMY's 80m 2W TNT

When it comes to the BK ... if you build it, they will come. Hopefully you can join the fun this winter as well.


Steve McDonald, VE7SL, is a regular contributor to AmateurRadio.com and writes from British Columbia, Canada. Contact him at [email protected].

One of the mantras of us old hams is; where are the youth? Many club meetings are consumed with the question of how do we connect with youth and get them exposed to Amateur Radio? One very simple way to get involved is to participate in the Worldwide Scouting event Jamboree on the Air (JOTA). This is the 60th Anniversary of the event.  Over 1 million scouts around the world participate. There are numerous ways to participate either hosting a station or getting on the air to talk with the scouts. Check out www.K2BSA.net/jota for information on the event. The dates are October 20 -22, 2017.

Another source of information is the recent Episode of HamRadioNow which is a round-table  of Scout leaders on the benefits and some methodology of JOTA. I was honored to be asked to participate. I think you will find the show to be informative with regard to JOTA.

Here is the link:

https://www.hamradionow.tv/episodes/2017/10/2/hrn-347-old-jota

Participate if you can.

                                              




Mike Crownover, AD5A, is a regular contributor to AmateurRadio.com and writes from Texas, USA. Contact him at [email protected].

In this episode, Martin (M1MRB/W9ICQ) is joined by Chris Howard (M0TCH), Martin Rothwell (M0SGL), Dan Romanchik (KB6NU) and Ed Durrant (DD5LP)  to discuss the latest Amateur / Ham Radio news. Colin M6BOY rounds up the news in brief, and this episode’s feature is SDR Play.

We would like to thank Dave Bowie (ZL4DRB) and our monthly and annual subscription donors for keeping the podcast advert free. To donate, please visit - http://www.icqpodcast.com/donate

• History of UK Special Contest Call Signs
• New Digital Voice Repeater for Southern Ireland
• Individual Licences Legal in Tunisia
• American Red Cross Asks ARRL’s Assistance with Puerto Rico Relief Effort
• VERON & Regulator to Discuss RF Pollution
• New US Personal Radio (Part 95) Rules Take Effect
• Ham Plans Community Station
• Falconsat-3 Available for Amateur Radio
• Yasme Foundation Grant to ARRL Ham Aid Fund

Colin Butler, M6BOY, is the host of the ICQ Podcast, a weekly radio show about Amateur Radio. Contact him at [email protected].

Amateur Radio Weekly is curated by Cale Mooth K4HCK. Sign up free to receive ham radio's most relevant news, projects, technology and events by e-mail each week at http://www.hamweekly.com.

Stories you’ll find in our October, 2017 issue:

October 4, 1957: The Beep Heard Around the World
By Richard Fisher KI6SN

Listening and peering into the night sky on October 4, 1957, hams, shortwave listeners, scientists, military personnel and ordinary citizens became eye and ear-witnesses to an epic moment in human existence—the dawn of the Space Age. Richard has collected the thoughts and memories of those who were among the first to hear and see the original man-made moon, known as “Sputnik-1.” The historic event not only changed the course of human history, but also changed the lives of many of the individuals who heard those first beeps from space.

A Visual Tour of the Tokyo Ham Fair
By Keith Baker KB1SF/VA3KSF

In early September, Keith had the distinct honor of being an ambassador for the Dayton Amateur Radio Association (DARA) at the big Tokyo Ham Radio Fair in Tokyo, Japan. He writes, “Our mission was to personally invite Japanese hams to join us in Dayton, Ohio, for next year’s big Dayton Hamvention. However, unlike the Dayton Hamvention, which is sponsored by a local (albeit large!) amateur radio club (DARA), the Japan Amateur Radio League (JRRL), the Japanese equivalent of our American Radio Relay League (ARRL), conducts the Tokyo Ham Fair each year.” Keith also visits the Akihabara section of Tokyo known as “Electric Town” and presents a visual tour of both.

TSM Reviews: Digitech AR1780
By Thomas Witherspoon K4SWL

Regular contributor, Thomas Witherspoon, is always on the lookout for interesting, unheralded shortwave radios. This month he takes a look at the Digitech AR1780, a relatively unknown, inexpensive portable shortwave radio that covers longwave through shortwave, FM and even the Air-band and, while it has some quirks, it has more than a few features in its favor. Find out why Thomas says, “For $129.00 AUD (roughly $103 USD), you’re getting a full-featured radio that is, by and large, a pleasure to operate.”

The European DX Council at 50
By Chrissy Brand

It was 50 years ago, in 1967, that the first conference of the European DX Council was held. The EDXC, an organization of leading DXers, is still going strong after all these decades. This is testified by the continued success of its annual conference and through the projects and information sharing that it still carries out. Chrissy reports on this year’s conference held in August in the Finnish city of Tampere.

Tran-Equatorial Propagation: Pillows in the Sky
By John Piliounis SV1OCS

Most radio communications at VHF frequencies happens between different locations in line-of-sight propagation and, more rarely, either through the E or F2 layers’ ionospheric refraction during periods of intense sunspots, or through tropospheric ducting. But Mother Nature has provided VHF communication links that also happen between symmetrical locations to the geomagnetic equator. Propagation of this type has been named Trans-Equatorial Propagation (TEP). John looks at the theory behind this phenomenon and the historic experiments to prove its existence to skeptics.

Scanning America
By Dan Veeneman
Post Falls and Kootenai County, Idaho

Federal Wavelengths
By Chris Parris
Eclipse, Weather Provide Scanner Action

Milcom
By Larry Van Horn N5FPW
Introduction to Military Monitoring:
What Equipment do you need to Monitor HF MilComms?

Utility Planet
By Hugh Stegman NV6H
Summer 2017: Nature Gets the Last Word

Shortwave Utility Logs
Compiled by Hugh Stegman and Mike Chace-Ortiz

VHF and Above
By Joe Lynch N6CL
A DIY Hardware Store 2-Meter GOTA/EMMCOM Antenna

Amateur Radio Insights
By Kirk Kleinschmidt NT0Z
The Twists and Turns of Amateur Radio Rotators

Radio 101
By Ken Reitz KS4ZR
Monitoring Emergencies via FTA Satellite

Radio Propagation
By Tomas Hood NW7US
A Last Hoorah?

World of Shortwave Listening
By Andrew Yoder
AM and SW Pirates: Then and Now, Plus: Global HF Pirate Weekend

The Shortwave Listener
By Fred Waterer
BBC Program Notes for October and More

Maritime Monitoring
By Ron Walsh VE3GO
Nothing Remains the Same Except Change!

The Longwave Zone
By Kevin O’Hern and Cary WB2QMY
Get it in the Log!

Adventures is Radio Restoration
By Rich Post KB8TAD
Re-converting a Radio for the Summer of ’42 (Motorola 50P for Pontiac)

Antenna Connections
By Dan Farber AC0LW
Getting High: Antenna Effects and Oddities at UHF and Up

The Spectrum Monitor is available in PDF format which can be read on any desktop, laptop, iPad®, Kindle® Fire, or other device capable of opening a PDF file. Annual subscription is $24. Individual monthly issues are available for $3 each.

Ken Reitz, KS4ZR, is publisher and managing editor of The Spectrum Monitor. Contact him at [email protected].