sight unseen

the habit of trusting people

de bill K7WXW

Almost every piece of radio gear I own, outside of hand tools, a DVM and the task light over my bench, is used. I love a good bargain as much as the next ham but that’s not my primary reason for buying other people’s stuff.

I recently purchased a magnetic loop antenna from a ham in Oklahoma, whom I will call Sam. He’s decided to focus on portable operations that don’t involve lugging stuff up and down mountains; the loop is “excess to his needs”. I love being outdoors, have been putting together a backpack-sized kit for portable operating, and enjoy mucking about with antennas. We are a match made in heaven.

We exchanged emails. Sam offered a fair deal and I didn’t haggle with him. Before I dropped the postal money order into the mailbox, I sent an email to confirm his address. He replied, confirming his address and letting me know he had already shipped the antenna. I mailed the money order.

Wait… he’d already shipped the antenna?

Sam and I have not met. We’ve not had a QSO, live approximately 1900 miles apart, and only know each only through our postings to an email list to which we both belong. We are, by conventional measures, strangers. Yet he sent me an antenna without having cash in hand and I did the same thing going the other way. Are we crazy?

Perhaps. I do prefer Paypal to money orders and I checked his QRZ page to be sure that an enterprising con artist wasn’t using an unsuspecting ham’s name and call sign for a scam. That was the extent my diligence, a fact which an younger version of me finds quite remarkable. But our email exchange was so straightforward that the QRZ bio page check just confirmed my gut call: this is a honest guy, I don’t need to to anything else.

Truth is, most of my ham gear buying and selling goes this way.  Sure, I’ve encountered a few cranks, grouches and one or two outright thieves but mostly I deal with people like Sam, honorable folks that follow the golden rule.  And the pleasure of encountering them, even if it is only through email, is one of the benefits that the exam study guide didn’t cover.

And each one still surprises me coming, as I do, from a world which valued besting the other guy above just about everything else. I am fortunate: as a ham, people like Sam happen along often enough to suggest a different kind of world is possible. I am grateful for the reminder.

Thanks Sam. I hope I have a chance to work you on 40 meters sometime.

A Homebrew QRP Radio Station

A Two-Watt Transmitter – 40-Meters and 80-Meters.

The Radio Shack DX-392 Served As The Receiver.

The key is a US Navy Flame-Proof Key.

It may be twenty years since Ernie, KB7HCW, and I were busy building low-power radio stations and seeing what they could do. If Ernie hadn’t passed on we might still be at it.

Ernie served on 11 ships during 22 years in the US Navy. After retiring he earned an Electrical Engineering Degree and a second Class Radio Telephone License. I met him after he’d set up a shop for repairing CB radios. However, I’m not sure he ever fixed a CB. Instead, he and I spent our time playing, seeing how far we could communicate with “flea-power”.

This particular station is built for Morse code – CW. It still has the crystal we used for participating in the Idaho-Montana Section Net. We moved some messages, but we didn’t hurt anyone’s ears doing it.

We had fun fun fun.

 

Ground Bars and Bolts

By Bill

The ground bar is bolted down on the shelf. The grounding straps of tinned copper braid, between the bar and my rig, power supply and tuner, are done and installed. I am holding the last one, which will connect to the case of the filtered AC outlet box, in my hand. The filter is on the floor near the wall outlet, as planned. But it is not going to work. If I follow my original plan, the strap will be a four-foot long invitation to a ground loop. I set it on the floor and look around for my notebook.

Other design choices I made aren’t working out either. I start making a list. For example, to work behind my rig, I have to move the desk. To move the desk I have to get out a quarter-inch socket driver and unhook the copper strap that ties the ground bar to the rod outside. Inevitably I drop the bolt holding the strap and end up crawling under the desk to retrieve it. When I am done, I have to reverse the procedure. I try to skip over the dropping-the-bolt step. It is not, as they say, an optimized process. Or as I say, this is a drag, gotta fix it.

As an engineer, I learned quickly that paper designs failed in unexpected ways in the real world of voltage, screws, panels, and cable. As in what could have possibly been thinking when you designed that? Mostly, the stuff I built fails to work in small ways: screws that hard to reach, transistors pushed a little too close their specs, current requirements not quite met. I am not alone in this, for it is practically impossible to figure out beforehand how exactly the thing we are designing is going to be used until someone actually uses it.

A ground bar. A piece of gear can’t get much simpler than a copper bar with holes drilled in it, a couple of standoffs, and a fistful of 4-20 nuts, lockwashers, and bolts. Bolt the bar to the desk, secure each ground strap with a bolt, lockwasher, and nut. Easy, right? Not so much. The way I designed it, unbolting the main ground to get behind the desk is a giant hassle. The ground strap to the AC line filter is way too long for comfort. And with a single bolt, nut and washer per strap it takes two hands and two tools to work on a connection. This stuff clearly needs to be fixed. Should be easy.

My first inclination is to fix it now! But giving into this inclination almost always turns out, even in the simplest cases, to be a bad idea. Like most people, my first unvarnished solution to a problem is usually (never) my best one. It is rarely even my second or third best one. I don’t automatically trash the first thing that comes to mind, I just make it the first item in a list of possible fixes.

Bench engineers know all about engineering change orders. Even the best product designs don’t get through the design-build-ship cycle without them. ECOs are another version of my lab notebook: what is the problem, what is the fix, what does it affect, how much does it cost? An engineer that has to fill out an ECO form and get it approved by the people who have to live with the change – manufacturing, marketing, testing – is an engineer that has to think through the problem he or she is trying to solve. Whether I was the designer or the design team manager, ECOs were my antidote for the spontaneous fix.

I don’t have a marketing department and I manage all the manufacturing and testing around here. The only person that needs to sign off on what I do is me. If I end up spending a lot of time fixing the damage one of my fixes causes, I am pretty sure I know who screwed up. Since I don’t enjoy fixing my own mistakes, I’ve adopted the spirit if not the form of the engineering change order process.

In my case, I start by looking at my original design. What was I trying to do? I want to be sure I understand my original design goals. Then I make a list of the problems in the current design and I ask myself if any of the problems are a result of the original goals. If they are, and I can’t come up with a fix, I either live with the problem or I change the goal. If I start fixing stuff before this work is done I am pretty sure I am going to have another oh yeah I forgot I needed it do to this! moment sometime soon.

I start listing possible solutions once this work is done. And when the list is done, I set it aside for a bit, and on returning, try to improve the solutions. The list rarely has more than three or four choices; I just don’t have that many good ideas. A little work here and the best answer starts to stand out. Yes, I write all this stuff down. Why? Because I don’t like having the same bad idea more than once. This is my version of the ECO: a detailed lab notebook record of what I am fixing and why, without all the check boxes and signature blocks.

Sometimes I discover that I actually don’t know what to do next. When that happens, I set my list aside and go do the research I need to do. Better not to fix something than to try something, hoping things will turn out okay. Addressing the issues with the ground bar was straight forward but I decided to do a little research anyway. That research validated my ideas. I was good to go.

I worked through my fix list. The bolts are installed from the bottom of the bar with a lock washer and nut on the top side. Now they don’t need to be removed when I have to disconnect a ground strap. The ground that runs outside has a wing nut instead of a nut, so I don’t need a wrench or nut driver to take it off. I mount the AC line filter to the underside of the desk. Now its ground strap is six inches, rather than four feet, long. I can’t do much about disconnecting the outside ground every time I need to get behind the desk. That strap has to be as short as possible and unless I put the desk in the middle of the room, I will continue to need to move it to get to the back side of my gear.

After the fact, the fixes seem pretty simple and might hardly worth all the writing stuff down. Bill, that sure seems like a lot of work for a small problem. Couldn’t you just try something and see how it worked? Perhaps. But experience suggests that simple fixes are simple because they are thought through and thinking it through requires a record of what one is doing and why. Honestly? It took me longer to write about this piece about documenting the design process than it did to actually do it. That isn’t always the case. The chance of getting something wrong in a design goes up as the square (or worse) of the complexity. Building time into the process for making, testing and documenting changes at the front end saves a lot of confusion and frustration later.
I disconnect one of the ground connections to re-route it so it won’t block access to one of the antenna feeds. After I check everything against my wiring diagram, I plug gear into the new AC filter and the filter to the mains before pushing the desk back against the wall. Getting behind the rig is a lot easier than it was two hours ago, which was the goal. And three months from now when I am trying to remember why I did what I did, I have my notes. It works.

Writing It Down

Building a radio station from scratch is involves more planning and work than meets the eye. My friend, Bill, has demonstrated this in the  a series of articles that  follow.

By Bill

 

I need an entrance panel for my antenna feeds. Snaking them through a partially open basement window isn’t working out so well. I look over the ready-made options and decide to design and build my own. What I come up with will work electrically but I have a problem: I have no idea how to bolt it all together.

Figuring that out involves a notebook, one 6×12 inch sheet of aluminum and a pile of lightning suppressors, all of which are on my desk, next to the keyboard. I’ve been doing this for a while; it’s a hard problem. A bigger piece of aluminum would be better but won’t fit in the space I have, the components are oddly shaped and the whole thing has to go together in a way that allows me to easily attach and route cables. Every once in a while, I re-arrange the pile, make a quick sketch and write another note.

The notebook is a product of Mr. Sivak, my junior high school science teacher. To get a passing grade, our notebooks had to formatted in a certain way and include certain stuff: the hypothesis, lab setup, initial conditions, experiment protocol, and results. There was, being high school, a lot of grumbling in the ranks. More writing? More rules? More stuff that I will never use again? Me? My resistance faded when I figured out that keeping records of my experiments enabled me to understand why things worked the way they did.

In science class, the notebook trained me to capture information in a way that made it useful. It also taught me cause-and-effect: I did this and that happened. As a vo-tech student, it cut down on the number of times I made the same mistake.

Later when I was learning electronics on a tube trainer rack made up of a pre-built plug-ins – power supplies, amplifiers, oscillators and such – I used a lab notebook to keep track of my choices. Recording what I did mattered because passing the class involved (a) developing a  design by the deadline and (b) not letting the smoke out of the same type of plug-in twice while doing so.

In the years that followed I filled a lot more notebooks. I stopped doing engineering bench work, but I kept using lab notebooks. Whatever name I used for them, the essential components – initial conditions, hypothesis, setup, protocol and results – that made up my high school lab notebook didn’t change. Whether I was building or managing or monitoring, whether it was a new product or a new company, using this format to guide my decisions simply made whatever I was doing turn out better. The notebooks of my professional career helped me develop, test and, most importantly, assess and tune good solutions to complex problems, which is what I got paid to do.

Today, I am on the eleventh arrangement of the panel. I have solved a couple of problems that I didn’t know I had when I started. I notice that the difference between the tenth and eleventh versions is pretty small, so I probably have a design that meets my goals. But if I build it and find a new problem, the next version can skip past all the designs I have already tried and rejected. The sketching and note taking added about an hour to the process. From past experience, I am certain that hour will save me from having a, “wish I had thought of that before I started drilling” moment, and rework or starting over, later.

I decide to try one more arrangement of the panel. It looks familiar. Reviewing my notes, I see it’s a repeat. But flipping one of the components around solves a spacing problem that’s stumped me until now.

Finished! I make one last sketch. Later I will use some LMR400 coax I have (my worst case scenario) to make sure my cabling assumptions are okay. Finally, I will dimension the components and make a drawing that will serve as the panel’s drilling template.

After measuring each of the components and making the drill template, I make a final parts list so I know what I need from the hardware store. It will take just an hour or two to drill the aluminum and assemble the panel. With all the arranging and sketching, I am confident that my cabling problem is solved, I’ve addressed the lightning and static charge problems, and I have a way to review my design choices if I want to make changes. Not a bad day’s work.

Why should hams bother with lab notebooks? It’s a hobby. Diplomas, promotions and stock certificates do not hang in the balance. An hour writing is an hour not devoted to making contacts. But anyone who has invested days in building an improvised piece of gear that doesn’t work or fit or last knows my answer: I suck at making things up on the fly. Every hour of designing, paper testing and documenting saves me two or four or more hours of rework later. And six months later, when I don’t remember why I made the choices I made – whether it is an antenna setup or homebrew balun or the way I configured my radio – my notebook has me covered.

A Raspberry Pi Adventure

 

The thing on the left is a Raspberry Pi Monitor.  On the right is the Raspberry Pi computer. It’s not very powerful compared to those we are used to these days. Even computing power of a cell phone exceeds the Pi many times over. So why mess with it in this day and age? Because it opens the field for experimentation, new things to learn, new challenges, new things to accomplish.

A few years back I acquired an interest in the Pi and attended a few group-meeting at the University of Texas, Dallas. A software engineer seeking new ideas headed the meetup and I took a lot of knowledge home with me.

Along the right-hand edge of the computer is a double row of small vertical pins. The monitor has a matching plug that mates like a sandwich. I bought the monitor. When I plugged it in and turned it on the display was hard against the right margin. That didn’t hurt anything, but it bugged me.  I wanted it centered. I began experimenting with the placement code and after a dozen times the monitor turned dark.

In my search for the cause I discovered the codec (the black square just below the raspberry symbol) was hot enough to cook my breakfast. Shucks! Disheartened, I stored it in an iPhone box and thought about it for a few years.

Today, I ordered another Pi and a terminal node controller. When everything is assembled and I better understand what I’m doing I’ll start sending amateur radio messages without the Internet, drawing power from a solar panel and eventually joining up with the emergency communications (EMCOMM) and strut my new toy.

I won’t be using my cool monitor. I’m not sure what took the codec out, my coding or something in the monitory bit the dust.

So, the saga begins.

 

The Desert Rat

I

Bob

I met Bob in Ajo (Ah’-hoe) on a summer afternoon of 1999. Since Barb and I were cyclists, tandem cyclists to be precise, he caught my attention with his bicycle and two large trailers, so I picked his brain, as much as he would let me. What was he thinking?

He hailed from North Carolina, as I recall. A TV documentary had piqued his interest in the American Southwest. Since he had no family to whom he had to answer he quit his job, purchased a Walmart bike, and then headed west.

We didn’t discuss how he wintered. Obviously, he found somewhere to await warmer temperatures.

By the time he reached Teec Nos Pos in the Navajo Nation  near Ship Rock a year had passed and he was a seasoned cyclist – enjoying the good, tolerating the bad. And he had learned to become nearly invisible, or would have remained so had he not decided a bicycle would not carry all the things he held dear. Therefore, he built a bike trailer from discards scavenged from an unattended landfill.

I’m don’t recall what compelled him to build a second trailer. But both trailers were so heavily burdened he said he could no longer ride the bike except downhill. Instead, he pushed it.

He told me he was road weary. His bike and two trailer had satisfied his yearn to see what lay over the next hill, or around the next turn. He no longer cared. He was now searching for a more conventional lifestyle.

The last time I saw him he was managing a RV park at the western boundary outside the Tohona O’oham Indian Nation. He’d lost some of his crispy critter look, having taken shelter from the blazing Arizona sun.

His bike and trailers were nowhere to be seen.

met Bob in Ajo (Ah’-hoe) on a summer afternoon of 1999. Since Barb and I were cyclists, tandem cyclists to be precise, he caught my attention with his bicycle and two large trailers, so I picked his brain, as much as he would let me. What was he thinking?

He hailed from North Carolina, as I recall. A TV documentary had piqued his interest in the American Southwest. Since he had no family to whom he had to answer he quit his job, purchased a Walmart bike, and then headed west.

We didn’t discuss how he wintered. Obviously, he found somewhere to await warmer temperatures.

By the time he reached Teec Nos Pos in the Navajo Nation  near Ship Rock a year had passed and he was a seasoned cyclist – enjoying the good, tolerating the bad. And he had learned to become nearly invisible, or would have remained so had he not decided a bicycle would not carry all the things he held dear. Therefore, he built a bike trailer from discards scavenged from an unattended landfill.

I’m don’t recall what compelled him to build a second trailer. But both trailers were so heavily burdened he said he could no longer ride the bike except downhill. Instead, he pushed it.

He told me he was road weary. His bike and two trailer had satisfied his yearn to see what lay over the next hill, or around the next turn. He no longer cared. He was now searching for a more conventional lifestyle.

The last time I saw him he was managing a RV park at the western boundary outside the Tohona O’oham Indian Nation. He’d lost some of his crispy critter look, having taken shelter from the blazing Arizona sun.

His bike and trailers were nowhere to be seen.

Living In the Henry Mountains

I earned my amateur radio license nearly 30 years ago. During that time my primary interest has been the use of Morse code. As a result I’ve read extensively about Samuel Morse, the man credited with the development of this language.

Morse searched for someone who understood the principles do electrical magnetism. And in his quest he located this person, a West Virginia country school teacher, Joseph Henry who went on to become the first president of the Smithsonian. The wisdom Henry shared with Morse made the telegraph system a reality.

By this time all the North American mountain ranges were already named except for a small range up in Southeast Utah, which was named in his honor.

About 20 years ago Barb and I found ourselves within a half-day’s drive of Southeast Utah, so we headed north for a look at the Henry Mountains. ONce there, we discovered the Butler Ruins.

(I apologize for the grainy photo. Evening comes early to the Henry Mountains, and the shadows were already gathering.)

However, a closer look at the “backwards “C” will reveal a cliff house tucked into the back wall.
This photo made the entire trip a success even if the quality is poor. It was taken with 35mm film asa 100. Trying to reproduce it with a Google Tablet hasn’t made it any better.

C-119 aka Flying Boxcar


A bit of background on this aircraft.

The Flying Boxcar was a front line aircraft during the early 1950, and beyond. The rear section of the fuselage could be removed, leaving it wide open for serving the purpose at hand. A late friend had served as a C-119 crew chief helped deliver hay to starving livestock during the severe blizzards of 1951 – 1952.

During the early space shots a C-119 was used to snatch a parachuting reentry probe in mid-air.


This photo shows a C-119 preparing for restoration before being moved to a museum. bit of background on this aircraft.

*

In 1964 I was stationed at Ramey AFB, Puerto Rico. The US was fully engaged in the Cold War. SAC had settled down to a dull roar supporting Chrome Dome and maintaining training missions.

Our shop was located on the south side of the runway. On the opposite side of the runway were the hangars and the tower. The entryway faced west.

One evening a fellow airman burst through the shop door. “THERE’S A U-2 ON THE GROUND!” he shouted.

None of us had ever seen a U-2 in person, so to speak. So as a body of one we rushed the door. But our quest was fruitless. The aircraft ground-support team, in their efficiency, had already directed it into hangar 2 and all we saw was the doors closing on a darkened hangar. However, we knew sooner or later they would have to bring it out. We would be ready.

The following morning the doors opened and from the darkened interior came the aircraft and it took off directly into the sun. We saw nothing. Two more days this was repeated, and on the third evening it didn’t return.

Ramey was buzzing with rumors, which obviously generated an official announcement. The U-2 was here for air samples, it stated

Who would ever believe such a cock and bull story as that?

Years later I learned that missiles give forth an odor that can be detected and with the proper equipment and skill missiles can be identified without a visual image.

Weeks later the Dominican Republic Crisis evolved. It was a Communist attempt to create a second Cuban Missile Crisis. But this time the United States was ready.

Our first clue that something was afoot was when TAC, the Tactical Air command, arrived with 12 combat aircraft and a C-135 carrying supplies, equipment, and a crew of maintainers. They even brought their own shop and chow hall. All they needed from us was water and fuel. Two hours after their arrival two reconnaissance aircraft headed out to photograph the situation.

The following day other aircraft – additional combat aircraft and cargo aircraft arrived. They were parked on every square foot of concrete.

Cargo crews were instructed to log 60 airborne hours before time off. After a couple of days they began writing up phantom problems with the aircraft in order to earn a bit of downtime. I could hardly blame them, but that put our radio shop to the test.

We were well into the crisis when I picked up a work order stating that the HF radio was inoperative at the navigator’s position on a C-119

The entryway is at the rear of the fuselage and it was pretty well filled with a C-124 engine. Having not been aboard a C-119 for at least six years I lurked behind the engine a minute or two in order to familiarize myself.

The flight crew members were old, gray-headed men. The navigator, a major, was busy sorting through his maps, preparing for departure.

Since the navigator needs the use of both hands, he has a floor switch for keying the transmitter. To accommodate this switch there is a space large enough for the navigator’s shoe, but guarded to prevent accidental use. The navigator found this space a convenient place for his heavy map case. He was not aware that the weight had keyed the transmitter, which in turn activated a T/R switch that electrically removes the receiver so it isn’t damaged by the RF power.

“Are you the radio man?“ he asked, looking up from his maps as I set my tools on the floor.

“Yes I am, sir.”

“Good. The HF radio doesn’t work. We’re going to need it with 900 miles of water to cross.”

“Your map case has turned the receiver off, sir” I said pointing, but not touching stuff.

“What?”

“It’s setting on the mic switch and it’s activated the T/R switch,sir.”

“So that’s were that foot switch is,” he muttered.

“Let me check it out, sir,” I said.

He got up front his chair, but he was right at my elbow. It was obvious he didn’t trust me, so I switched the audio from headset to speaker and turned the gain up so he could hear what I was hearing. And then I called McDill AFB in Florida, Charleston AFB in south Carolina, and the Andrews Airways in Washington, D.C. for radio ground checks. All three reported loud and clear.

I stood up and reached for the aircraft log to sign it off, but he was gun-shy of the radio and insisted I wait for him to check it out himself. So I waited and watched him return the map case to where I’d found it.

“it’s quit again,” he said

“I know, sir, you’ve sat your map case on the mic switch.”

He was staring at the map case when I signed the aircraft log with a brief note that the system was normal and started for the door. The crew chief, a regular air force Staff Sergeant followed me out the door.

“These guya are reservists, you know. I don’t know what the navigator did before being called back, but the aircraft commander was driving a train. He is making some major errors. They’re going to kill me.”

I felt his concern, but there was nothing I could do but monitor the report for aircraft ditched at sea. I never saw a thing.

 

The Old Man

One evening I stopped by a Safeway store on my way home. When I came out the west entrance I found an old man with a cart full of things. I asked him if he needed a ride. He told me a taxi would come by shortly and he would flag him down. I insisted and at last he relented. After loading his stuff in my car we began the trek to his house which was no less than fifteen miles. Not a cheap cab ride.

Eventually, we reached his house.

A steep path led from the road to his house. As I started to help carry his stuff – which included a fifty pound bag of bird seed – down the hill he insisted that I set it out on the shoulder. His brother would come up the hill and help.

He was so stern that I did as he said. Before I drove back to down I snapped this photograph.