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Manager - AB7RG
Manager Notes

The Butterfly Effect

Created by Ulrich H. Steinberg, N2DE on 2020-08-24

"Editor's Note: Due to the popularity of some of eHam's older articles, many of which you may not have read, the eHam.net team has decided to rerun some of the best articles that we have received since eHam's inception. These articles will be reprinted to add to the quality of eHam's content and in a show of appreciation to the authors of these articles." This article was originally published on: 07/10/2008

 

In three previous articles on this site I have traced the development story of an advanced memory keyer, based on the AVR Butterfly microprocessor board, each time implying that there was essentially nothing more to be done - I'm wiser now and will not make that insinuation again. ( see http://www.eham.net/articles/11749 and http://www.eham.net/articles/14970 and http://www.eham.net/articles/16608 ). When I set out to do this, I had no idea that it would keep me busy for such a long time, let alone that I would spend literally thousands of hours making it all work. It turned out to be a perfect project to bridge the gap between the peaks of two solar cycles ;-)

 

Meanwhile the keyer has become a commercial product, the Begali CW Machine, with a small but dedicated group of users, and it is packaged in a nice enclosure that is made by TenTec. There is enough documentation of the hardware available online at http://www.i2rtf.com/docs/CWMachineHardware.pdf to let you build your own version of it if you are so inclined (you would still have to get the firmware and software from me, unless you want to spend a couple of years developing it yourself ;-)

 

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Countless suggestions have been made, and I myself as a power user have had a lot of ideas derived from daily use, and many of them made it into the product in some shape or form. Having spent so much time on the development, I pretty much felt that I had covered all bases and done everything that is doable in a memory keyer. That is, until I was hit with a harmless sounding user question that I had never thought about because I don't own the latest and greatest radios: would it be possible to use your paddle to send CW from a radio at another site that is connected to you over an Internet link?

 

A little background is required to understand why this is a tricky issue, and nobody to the best of my knowledge has so far been able to do this in a convincing fashion.

 

Some modern radios can be completely controlled and operated by software that runs on a PC that is attached to the radio. Then there are packages on the market, and even built directly into Windows XP and Vista, that let you "see" and operate a PC over the Internet from another PC or laptop at a remote location. You can even hear the sound of that remotely controlled PC. Put these two together, and you have the building blocks to operate your radio from anywhere in the world. You hear the sound from your rig via the sound card connection, and talking into a microphone will send your voice via the sound card into your rig and out on the air. The TenTec Omni VII takes this one step further and eliminates the need for the remote control software by putting the Internet connectivity right into the radio.

 

So, how do you send CW with this kind of remote setup? The only answer so far has been to use a keyboard and to type text into a program that converts it to CW at the radio site. You can't use paddles because the information about closing and opening a contact, if you could send it over the communication link, would be distorted by the minute delays and irregularities in the connection, and it would be impossible to send clean CW this way.

 

I am a reasonably good typist, but I have never quite grown accustomed to using a CW keyboard for anything but short contest exchanges, where all you practically type in is the other stations call. For "real" CW QSOs I prefer my paddle by a mile. So how can a guy like me use his beloved paddle with a remotely controlled radio?

 

After some thought I realized that the CW Machine firmware / software combination has all the basic building blocks to make remote "paddling" a reality, and after some more days of programming the first prototype actually worked! At the core of the idea is the fact that the CW Machine firmware translates paddle movements into readable characters which scroll across the LCD screen of the device, and which are also sent to a companion Windows program, the CW Machine Manager, where they show up on a monitor screen.

 

The CW Machine now supports several techniques to make remote CW a reality, depending on whether you have CW Machines on both ends of the communication link or just one CW Machine, either at the radio location or at the remote site.

 

The simplest approach, assuming that you have only a CW Machine connected to your radio, is to just use a remote desktop program that lets you start the CW Machine Manager and the radio control program. The CW Machine Manager has a sophisticated CW keyboard function, far more advanced than a typical CW keyboard program - so this appears like a pretty good solution. In practice, however, typing over a remote desktop link is often a pretty frustrating experience, with characters being randomly delayed, and the end result is a choppy CW signal that is hardly acceptable. (There are functions in the CW Machine Manager to mitigate that issue, but it is far from the experience that you have with a paddle.)

 

The second scenario is that you have a CW Machine with you at the remote location and just a CW keyboard program at the radio site. You bring up the CW keyboard program on your remote desktop, similar to the CW Machine Manager program in the first scenario, and the CW Machine that you have with you is now able to "trick" that program into reading the characters that you create with a paddle just like you had typed them in on the keyboard. Now you're using your paddle for CW! That's a big step, but some issues have to be solved. The CW keyboard program will in all probability use different characters to represent the operational prosigns. The CW Machine, e.g., uses the # character for the [sk] prosign, while the TenTec Omni VII uses a > for that purpose. Also, the CW Machine supports many foreign characters, like the Spanish or German Umlaut characters or the Icelantic Thorn character. You probably didn't know that there was a Morse encoding for those, and neither do most CW keyboard programs, which either do nothing or send garbage when they see these strange beasts. Fortunately these issues have an easy solution. What remains is the issue that the remote desktop connection may introduce fluctuating delays that result in a choppy CW signal.

 

Another tricky issue is, that the CW keyboard program is operating at a particular speed which can hopefully be controlled from your remote location, but the CW Machine that you use with your paddle is running at the pace that you set with the speed potentiometer. As long as these two speeds are about the same, there is no major problem, but whenever you readjust your speed potentiometer, you have to make the corresponding change in your radio control program to keep both sides in sync. It would be nice if the speed of both sides could be synchronized by just turning the speed potentiometer on your CW Machine.

 

And that is where the third technique comes to the rescue, which requires that you have CW Machines in both locations. The CW Machine Manager can now operate as a server at the radio location which "talks" directly over the Internet to another CW Machine Manager at your remote location. Turning the speed potentiometer at the remote location automatically adjust the speed on both sides, and, since they both support the same character set, the compatibility issues mentioned above don't exist. Since the communication technique does not involve simulated or real typing, it is practically immune against minor fluctuations in the link.

 

It feels almost magical when you turn the speed potentiometer of a CW Machine in a hotel room somewhere, and you know that the CW Machine at the radio will faithfully track that adjustment. And when you use your paddle to create characters they will come out as perfectly spaced CW at the radio site.

 

This type of remotely controlled operation may not be legal everywhere, and you have to consult your licensing rules and regulations. But then, it has to be legal only in the country where the transmitter is located, and your license must authorize you to operate in that country. This is "real" radio, using the Internet only as a fancy long cable that lets you adjust your radio and the attached CW Machine.

 

My intrepid pilot user, who put that harmless sounding question to me in the first place, is a ham in a country where this type of operation is still a matter of dispute - so let's give her/him the benefit of anonymity but a big applause. We had to resolve a few issues, but eventually I was able to operate an incredible station that I could never afford myself, from my crummy hotel room in NJ, using my favorite mode of operation - good old CW created with a paddle.

 

This new function of the CW Machine allows you to operate a Big Gun CW station from an apartment in the city, where you wouldn't even have the permission to string up a wet noodle for an antenna. Do I sense a business opportunity here, offering telecommuting to a super station?  ;-)

 

This works so well that I was seriously tempted to get myself a modern rig to operate remotely from the hotel rooms that I spend most of my nights in - but then, why not keep the green to develop more creative applications for the CW Machine, and find a few generous CW Machine owners who let me use their dream stations remotely every now and then? ;-)

 

Like with the famous "Butterfly Effect," small disturbance at your paddle can key up a kilowatt amplifier at a location far, far away, creating a storm of perfect Morse to be heard around the world.

 

73, Ulrich, N2DE

 

 

 

FRIDGEKACOOLER2020-09-08
The Butterfly Effect
It looks great!