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The Amateur Amateur: Talking to Myself

01/26/2013

By Gary Hoffman, KB0H
Contributing Editor

Kerchunk, kerchunk. You know what that noise means, right? That was the sound of me “testing my radio” when I first got my license. Bet you did it, too. Oh? You claim you never did anything so impertinent as to key up and unkey, just to convince yourself that you were transmitting? Okay, if you say so.

That first instance of me beaming radio waves to myself was done via simplex -- one handheld transceiver to another (and literally from one hand to the other). And having successfully kerchunked one radio, I turned around and kerchunked the other one.

Okay, it was a bit infantile, but somewhat satisfying. At least I did it low power and not over a repeater, and did follow up with a “KB0QGE testing” (just to make it legal).

A lot of water has flowed down the Mississippi since then (plus an ice age or two), but now I find myself returning to those early experiments.

No, I'm not reverting to my childhood or losing my mind. Well... not the former, anyway. This time there is actually a reason, a legitimate reason for talking to myself.

And digitally, no less.

Digitally Speaking

I’m part of the St Louis County ARES (Amateur Radio Emergency Service) team. As Assistant Emergency Coordinator -- Operations, I help develop nets, strategies, manage the website, print fliers, make buttons and so forth and so on. It’s something of a catchall job. One of our group’s most recent challenges was to figure out just how digital modes might help us perform our mission. Not falling under Training, Exercises or any other AEC’s purview, it automatically got shuttled to Operations. In other words, it became one of my jobs.

I was not the first person on our team to use digital modes, and I wasnt the first to try to introduce them to the group. Craig Hirsh, K0CMH, Craig Klimczak, K4LSU, and a number of others had done a lot of the pioneering work. They’d even held digital mode seminars, which helped some, but certainly showed us how difficult the task was going to be. We still run a weekly packet net that was initiated by the Craigs.

But digital never caught on with our group. We never did come up with a plan or a specific mode to use. There were a number of reasons why our digital efforts floundered. One was the perception that “packet was it.” We had a weekly packet net, and there was a statewide packet network build-out in progress (MEPN, the Missouri Emergency Packet Network). Also, many of our served agencies had purchased TNCs (Terminal Node Controllers).

But we never pursued packet heavily, and participation in the weekly net was light.

Meanwhile, in the general ham community, new developments were popping up at a phenomenal rate. It seemed like every time we blinked, there was a new Digital Mode of the Week. And every single one of them was “The way ARES teams are going to go.”

It was confusing and maddening. Our ARES Emergency Coordinator Steve Wooten, KC0QMU, said that we had to make a decision. I had a long talk with him late one night in a hospital parking lot (it was nothing sinister like Bob Woodward meeting with Deep Throat in a basement garage -- our team has monthly meetings at the hospital and there are often impromptu mini-meetings out in the parking lot afterwards). The key thing to come out of this particular chat was that rather than being driven by “What’s Popular Right Now,” we needed to figure out precisely what we wanted digital modes to do for us. We came up with a short list of tasks that we wanted digital to perform and we prioritized it. The primary item on the list was we wanted something that could rapidly transmit binary files.

Right! I had several different modes to try. But who could I test them with? By this time, most of our ARES volunteers were thoroughly confused by the digital soup and were awaiting guidance. Those who were adept at various digital modes lived too far away for us to make consistent simplex contact with them. What was I to do?

It looked as though I was going to have to start talking to myself again.

Beating My Head Against the Wall

The first trial was with packet radio -- VHF -- at 1200 baud. It wasn’t too difficult. I already had two stations set up to operate packet: One handled my home APRS station, and I used the other for our weekly ARES packet net on MEPN. I had never tried sending or receiving binary files, but there were plenty of ways to do it. Even relatively simple programs like Hyperterminal and AGWterminal could send files. The question was, could they do so effectively?

As it turned out, no, they couldn’t. Oh, sending and receiving binary files by packet wasn’t a problem. But the transfer took about a fortnight.

Okay, that’s a bit of an exaggeration, but even after being compressed, every Adobe or Microsoft document I tried to send took ages. That not only tied up the frequency, my transmitter heated up due to the long transfer time. Running at low power didn’t help much, and I wound up aborting each test rather than burning up my radio.

Packet radio was definitely out of the running, at least at 1200 baud. Since I had UHF radios, I did consider trying 9600 baud. The problem with that idea was that my Kantronics KPC3+ TNCs would not communicate with the radios at that baud rate.

Moving on to another popular digital mode, I decided to try NBEMS. No, it’s not the brand of chewing gum that Chuck Yeager was fond of. It stands for Narrow Band Emergency Messaging System.

NBEMS uses sound cards (internal or external) rather than TNCs, so I had to come up with a different configuration. Fortunately, I had a Signalink external soundcard device for my newest radio and a Buxcomm Rascal soundcard interface for my oldest radio. I had already set up one computer with the NBEMS software, so setting up the second wasn’t too difficult. The only real problem I had was adjusting the sending and receiving volumes, since my two antennas were relatively close to each other.

I’ll say right away that NBEMS is very flexible, can work with an awful lot of digital modes and is absolutely superb at sending formatted messages. NBEMS is actually a software package centered around a base program called Fldigi. Flmsg and Flwrap are used in message handling; the program that takes care of sending and receiving files is Flarq.

I beat my head against the wall a lot with this one (which was pretty painful, considering that my shack is in the basement and the walls are concrete). I knew that my only hope of sending a binary file at any reasonable speed was to use the digital mode MT63 -- the one mode that I could not get Flarq to use. I searched the Internet, found out what problems Flarq had with MT63, made the recommended adjustments -- and got nowhere. It just would not work for me, indentations in the wall notwithstanding.

Well, that sure looked like the end of the line, unless I wanted to buy much more expensive TNCs. I doubted very much, however, if I could convince very many ARES volunteers, or served agencies, to pursue that course. But then Craig Hirsh suggested that I try WinDRM.

Life Is But a WinDRM

Okay, why not? It was free software. It worked through sound cards, so I already had all the hardware I needed. By this time, though, I had put a second Signalink in my shack, so I wasn’t exactly replicating the configuration I had used with NBEMS. Nevertheless, I didn’t run into any difficulties. I downloaded and installed WinDRM on my two shack computers. Once I had made all of the necessary connections and set my radios, I started the test.

While NBEMS had been complex and had used multiple displays, WinDRM was simplicity itself. There was just one tiny window, not resizable, and not many buttons to push. The instructions were fairly easy to follow.

Initially, the test did not go well. I had some sending and receiving problems, but they turned out to be related to the Signalink settings rather than to WinDRM. Once I got everything properly adjusted, I took my test file and transmitted it.

WinDRM fairly flew through the file transfer. What would have taken about 40 minutes using packet took only two-and-a-half minutes using WinDRM. I was so stunned that I refused to believe it. But WinDRM not only not only transmitted the file in short order, the receiving software uncompressed it and called up an appropriate program to display it. I had sent a compressed PDF file. Moments after the transfer had completed, Adobe Acrobat activated and the uncompressed document popped up on my screen. Wow, what service!

Our ARES group’s digital saga is far from over, but I feel that we are now well on our way. The two Craigs will be giving a presentation on WinDRM soon, and I think that we finally have a handle on what we need to do.

I guess that sometimes talking to yourself isn’t such a bad thing after all.

Editor’s note: ARRL member Gary Hoffman, KB0H, lives in Florissant, Missouri. He’s been a ham since 1995. Hoffman says his column’s name -- “The Amateur Amateur” -- suggests the explorations of a rank amateur, not those of an experienced or knowledgeable ham. His wife, Nancy, is N0NJ. Hoffman has a ham-related website. Readers are invited to contact the author via e-mail.

 



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