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The Amateur Amateur: A Soggy, Foggy, Doggy Demo in the Park

10/22/2009

It was a harrowing trip, especially on the Interstate. Despite almost-zero visibility, many of the other drivers were blazing along at near-supersonic speeds. I didn't know whether their vehicles were equipped with radar or if they were simply insane. Either way, I kept my own speed down and drove white-knuckled all the way.

The fog remained impenetrably thick until I was within a half-mile of the demonstration site. Then suddenly, the fog vanished, the sky cleared and the sun shone brightly. It was as if I'd just driven out of The Twilight Zone. Or into it.

A Portent of Things to Come

I arrived at the event site, unloaded my field gear at the designated spot and then parked my car. Upon returning to my pile of stuff I just stared at it for a minute, trying to figure out what I should start assembling first: The canopy? The table? The antenna? There were a couple of people waiting to assist me, so I had to make a quick decision and tell them what to do.

Note to self: I need to break my field station setup into individual tasks and write easy-to-understand instructions so that volunteers can help me with only a minimum amount of supervision.

Our site was a large, somewhat hilly picnic area in one of the St Louis County parks. Chuck, N0EIS, was our site manager. Anticipating that we'd have the same number of participants as we'd had in past years, he had set aside the high ground for stations that would be operating on VHF and UHF bands; HF stations and the Welcome Table were relegated to the lower terrain. Since I was going to run a 2 meter SSTV (Slow Scan Television) demonstration, I was assigned a position at the top of the hill.

As it turned out, I was pretty lonely up there. Our demonstration was just one of many events taking place that particular weekend, and we had far fewer participants than we'd expected. There were no other stations at the top of the hill with me. All of the rest of our activities (and, of course, the food) were at the bottom of the hill.

Talking to the "War Room"

A typical field event is always too hot or too cold. This one was too cold. The temperature was in the mid-30s when I first arrived and the grass was still damp with dew. As the day wore on it crept up into the low 50s and the Sun eventually dried the grass.

All of the grass except, of course, that which was in the shade of my canopy; everything beneath it remained soggy and muddy. Occasionally I would look longingly at the dry ground just outside of my shaded area, but once my station was set up, there was no way that I was going to take it down. If I tried to move everything, even a few feet, it would surely have ended in disaster.

Once everything was up and running I started cranking out SSTV signals. I wasn't really trying to send them very far, just to a receiving station down at our Welcome Table. There was an unattended station there that automatically displayed everything that I transmitted.

And I must say that SSTV was a pretty good way to demonstrate ham radio. Most of my non-ham visitors wouldn't have understood the differences between PSK31 and packet, or even between VHF and HF. SSTV had the advantage of being very visual.

I used a digital camera to take photos of each visitor. I then transferred the picture to my laptop computer, superimposed our ARES® group's call sign, and then transmitted it. I had a small police scanner tuned to the SSTV frequency so that my visitors could hear the distinctive chirping sounds. The audio-visual combination appeared to be quite effective. Most of my visitors sat and watched my laptop's screen for a moment, then scurried down the hill to the Welcome Table to see the images arrive. Even in this era of picture-taking cell phones, the demonstration seemed to amaze them.

The visitors who were ham operators talked shop, of course, but even they had a lot of questions about SSTV and connecting a laptop computer to a transceiver. The most common question, however, was about what kind of batteries I was using. That's always the most common question I get.

What Goes Inside

Okay, just for you technical folks, I do not use marine batteries. I use something called communications batteries. They are fundamentally the same (probably exactly the same) as batteries used in Uninterruptable Power Supplies (UPSs). Unlike marine batteries, they cannot give a surge of amperage to start motors. And unlike automotive batteries, they can "deep cycle," that is, they can be "run down" and then recharged without harming the battery.

A lot of people were also curious about my "battery carts." These were simple file folder boxes with built-in wheels and handles. They work fairly well, but as the batteries are significantly heavier than files, I fear that the boxes won't last for too many more trips into the field. Some day one of them will fall apart and dump its battery into a big pile of mud. Or something worse.

"A Silly Thing"

All right, you've been waiting to hear what went wrong. I won't keep you in suspense any longer. It wasn't anything major, just dead batteries. Only, it happened a lot.

First, the battery on my hand held transceiver croaked. Fortunately, I had anticipated this possibility and had brought a couple of spare batteries with me.

Next, I was talking to Steve, KC0QMU, our ARES® Emergency Coordinator, when I heard a faint beeping sound. Both Steve and I started performing the oft-seen comedy act of checking everything on our belts and in our pockets. Finding nothing on our persons that was demanding our immediate attention, we started looking through everything on the table. We finally determined that the batteries in my small police scanner had gone flat. Again, I had spares.

And then the digital camera died. Once again, I was prepared with a spare battery.

But the most perplexing battery failure was when my laptop computer complained that it was running low on power and shut itself down. That shouldn't have happened. I knew that the computer's own battery would last for only an hour or two, so I had connected it to one of my big 55 Ah batteries. From past experience I knew that this should keep the computer running for the rest of the day. What had gone wrong?

Well, what do you do in a situation like that? You look at each individual component in the system until you find the culprit. And in this case, it turned out to be an adaptor cable which had a female cigarette lighter socket at one end and Anderson Powerpoles at the other end. One of the Powerpoles had been poorly crimped and the wire was making only intermittent contact. That really irritated me since the adaptor was a commercial product, not something I'd cobbled together myself.

But once again I was prepared. I had spare Anderson Powerpoles and a crimping tool in my gear. I made the necessary fix and was soon back in business.

And not a moment too soon. The computer had died just as new visitors were arriving. One of the other ARES® members distracted them while I performed my search-and-repair operation, and I got everything running again before they got bored and walked away. Phew! Talk about a well-coordinated effort!

What a Way to Go

And so the day went, with me taking pictures, transmitting them and changing batteries. There were a few diversions, such as:

  • Chuck's chair sliding out from beneath him and dropping him onto the soggy grass.
  •  My handheld transceiver toppling over and hitting just exactly the right combination of keys to put it into Weird Mode (it was the following day before I managed to get it working again).
  • Man: "Did you see a large black poodle go by?" Me (pointing): "That way, 10 minutes ago." Sounds from the woods: "Woof! Woof!"
  •  Me going to the park's restroom and my cell phone falling into a puddle of glop. Fortunately (and unfortunately) it turned out to be liquid soap.

But sooner that I would have imagined, it was all over. Once the order was given to tear down, I just stared at my setup for a minute, trying to figure out what I should start disassembling first: The canopy? The table? The antenna? There were a couple of people waiting to assist me, so I had to make a quick decision and tell them what to do.

Note to self: I need to break my field station tear-down into individual tasks and write easy-to-understand instructions so that volunteers can help me with only a minimum amount of supervision.

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 Web page. Readers are invited to contact the author via e-mail.

 

Gary Hoffman, KB0H
Contributing Editor



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