In a recent conversation with my good friend Lewis, we started discussing Morse code, training and the old equipment that was used to educate and teach the code to newcomers. In particular we discussed the old Datong D70 practice oscillators.  Lewis carried on the tell me that his Datong  like so many others started sending odd illegal characters and essentially rendered the kit useless. Of course you could whip of the lid and replace the logic chips, but I thought of recreating the Datong functionality in a new Arduino sketch.

So here is a breakdown of what the Datong offered:

1. Either Mixed, letter or number combinations
2. Groups of 5 characters
3. Variable speed ( up to 37.5 word per minute)
4. Variable character spacing (up to 4 seconds)

The Datong also allowed you to connect a telegraph key, and your headphones. But for now I will focus on the code generation element of the project.

The finished project has just a handful of components and can easily be created on a breadboard, or indeed if you have an old broken Datong you can reuse the box and panel to really replicate the old kit.   The complete project includes 3 variable resistors (1K LIN) for Character speed, gap and volume. It also needs a 3 way switch to select the mode.

The Arduino I’m using is the UNO. Arguably the most popular Arduino on the market, but I have also tried the sketch on a Nano and it works fine – just some customisation of pin assignments is all that is needed.

On start up the Arduino checks to see which switch is LOW – it also saves the current mode and checks if the saved mode is the same as the current selected switch. If this is different, then the Arduino has had a change in the mode selection and resets.

When generating the tones, the Arduino randomly selects a character from an array. With that chosen letter – it calls a function and plays the corresponding tone functions. 2 functions exist as a DIT and a DAH.

The rest of the functions are dedicated to allowing the speed and gap to alter and also displaying the results on the LCD panel (completely optional).

Here is a short video of the kit working, and a link to the source code.

Dan Trudgian, MØTGN, is a regular contributor to AmateurRadio.com and writes from Wiltshire, England. He's a radio nut, IT guru, general good guy and an all round good egg. Contact him him here.

In a recent conversation with my good friend Lewis, we started discussing Morse code, training and the old equipment that was used to educate and teach the code to newcomers. In particular we discussed the old Datong D70 practice oscillators.  Lewis carried on the tell me that his Datong  like so many others started sending odd illegal characters and essentially rendered the kit useless. Of course you could whip of the lid and replace the logic chips, but I thought of recreating the Datong functionality in a new Arduino sketch.

So here is a breakdown of what the Datong offered:

1. Either Mixed, letter or number combinations
2. Groups of 5 characters
3. Variable speed ( up to 37.5 word per minute)
4. Variable character spacing (up to 4 seconds)

The Datong also allowed you to connect a telegraph key, and your headphones. But for now I will focus on the code generation element of the project.

The finished project has just a handful of components and can easily be created on a breadboard, or indeed if you have an old broken Datong you can reuse the box and panel to really replicate the old kit.   The complete project includes 3 variable resistors (1K LIN) for Character speed, gap and volume. It also needs a 3 way switch to select the mode.

The Arduino I’m using is the UNO. Arguably the most popular Arduino on the market, but I have also tried the sketch on a Nano and it works fine – just some customisation of pin assignments is all that is needed.

On start up the Arduino checks to see which switch is LOW – it also saves the current mode and checks if the saved mode is the same as the current selected switch. If this is different, then the Arduino has had a change in the mode selection and resets.

When generating the tones, the Arduino randomly selects a character from an array. With that chosen letter – it calls a function and plays the corresponding tone functions. 2 functions exist as a DIT and a DAH.

The rest of the functions are dedicated to allowing the speed and gap to alter and also displaying the results on the LCD panel (completely optional).

Here is a short video of the kit working, and a link to the source code.

Dan Trudgian, MØTGN, is a regular contributor to AmateurRadio.com and writes from Wiltshire, England. He's a radio nut, IT guru, general good guy and an all round good egg. Contact him him here.

In this episode, Martin M1MRB / W9ICQ is joined by Leslie Butterfield (G0CIB), Chris Howard (M0TCH) and Edmund Spicer (M0MNG)  to discuss the latest Amateur / Ham Radio news. Colin (M6BOY) rounds up the news in brief, and this episodes feature is Software Defined Radio Dongles.

• Bermuda Closes AM / Medium Wave Radio Transmitters
• Acorn II 40m SDR Construction
• Indian Government Employees to learn Amateur / Ham Radio
• Chess Controversy and Morse Code
• Ofcom Suggest 70.5 MHz for Internet of Things
• Reflectorless Yagi Radio Antennas Designs
• Councillors Vote in Favour of Ham Radio Mast
• Malta Digital Repeater

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

In this episode, Martin M1MRB / W9ICQ is joined by Leslie Butterfield (G0CIB), Chris Howard (M0TCH) and Edmund Spicer (M0MNG)  to discuss the latest Amateur / Ham Radio news. Colin (M6BOY) rounds up the news in brief, and this episodes feature is Software Defined Radio Dongles.

• Bermuda Closes AM / Medium Wave Radio Transmitters
• Acorn II 40m SDR Construction
• Indian Government Employees to learn Amateur / Ham Radio
• Chess Controversy and Morse Code
• Ofcom Suggest 70.5 MHz for Internet of Things
• Reflectorless Yagi Radio Antennas Designs
• Councillors Vote in Favour of Ham Radio Mast
• Malta Digital Repeater

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

Ham club newsletters exist in abundance. Most to inform members about upcoming events or to celebrate recently concluded activities with words and pictures. But there are those that serve a much larger audience — with timely advice and stories that cover the broader spectrum of amateur radio.

One of my favorites is The Gray Line Report — a quarterly publication of the Twin City DX Association.

The September edition is another good one. I’m reading ‘Adding an Amplifier to a Low Power Contest Station’ by Al Dewey, K0AD.

An there’s plenty more where that came from. Don’t miss it.

Tagged: dx, newsletter, tcdxa

Jeff Davis, KE9V, is a regular contributor to AmateurRadio.com and writes from Indiana, USA.

I recently had an inquiry about using 'MS Paint' for drawing PC board layouts. Although there are several freeware programs available for designing and drawing PC layouts, the ones I have tried had onerous learning curves. I also found that unless I was designing boards fairly regularly, I would have to go back and re-learn many of the functions each time I used the program. If you are regularly making a lot of boards, then these programs are certainly the way to go as they are packed with every feature you might need.

On the other hand, MS Paint meets all of my requirements and is simple to use ... I like simple. Although some might turn up their noses at MS Paint, I have found it to be a powerful and underestimated software tool. Here are some of the things that you might want to remember if drawing a PC layout with 'Paint'.

1. Take the time to read the built-in HELP and USING files. It doesn't take long to learn all of the functions along with some of the shortcuts.

2. Always draw with the IMAGE ... DRAW OPAQUE function turned off (unchecked). Do this first. This way, lines can go as close as you want without any blocking or overlapping. Try it the other way and you can see what happens.

3. If you are working with IC's, take the time to make a 'master' pattern that can be saved and copied anytime that you need it. A 16-pin layout can by used for 14 and 8 pin IC's by copying and pasting it and then erasing the unwanted pins. I can send you one via email if you contact me.


4. Similarly, once you have established the correct pad spacing for certain capacitors or resistor sizes, copy and save them for future use. Finding the correct spacing will require a few trial printouts so you can measure the exact gap.

5. For detailed work, use the VIEW ... ZOOM...CUSTOM  function to magnify the layout. This also allows you to use a grid if you find this helpful.

6. Never SAVE your layout while in ZOOM mode as you can't go back to the original size when you re-load your plan. I learned this the hard way.

7. For drawing perfectly straight lines, squares or round circles, hold the SHIFT key down when drawing the element.

8. For large areas of copper (groundplanes), outline the area then choose the FILL symbol to create the area.

9. With a little planning, you can almost always avoid jumpers to make a crossover connection, unless your circuit is very complex.

10. When you make a mistake, just use the EDIT ...UNDO command. You can go back several steps with this helpful function.

11. I will often draw a thin line between to pads to see if they are on the same level ... and then UNDO the line once I have checked.

12. Always SAVE your layout as a Monochrome Bitmap with the FILE ... SAVE AS function. Using some of the other modes will create less than solid blacks and some random pixels that can lead to etching problems.

13. If using the 'toner iron-on' method of etching, set your printer options to the highest resolution (mine is 1200 dpi) and then choose the darkest 'print' option. You want as much toner thickness as possible. Note that this method works only with laser / toner printers and not the ink-jet / bubble types.

14. For the iron-on transfer paper, I have had good success with the shiny yellow transfer paper widely available on E-Bay, usually with free shipping. I get the best results when pre-heating the PCB in the toaster oven before ironing-on the pattern ... not too hot to touch however.


If you just build the occasional PC board, you might find using MS Paint worthy of a try. It has been meeting my needs for many many years and once you have done a few, unlike some PC software, it doesn't take long to build a new board without having to learn how to use it all over again.


Steve McDonald, VE7SL, is a regular contributor to AmateurRadio.com and writes from British Columbia, Canada. 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.