H. P. Friedrichs (AC7ZL) Homepage
Radio Room
Barefoot On The Beach:
Casual QRP In A Tropical Paradise
Introduction
The phone in my office rang. I picked up the receiver. My wife's voice buzzed in the earpiece.
"Have you ever been to Puerto Rico?" She asked.
"No, why?" I chuckled, wondering what would come next.
She explained that her employer was sending her to San Juan for a week on business. "Why don't you go with me? It’ll be fun." Hmmm... Let's see... a nice hotel room, warm ocean air, the beach...she didn't have to twist my arm very far.
"That sounds great. I'll put in for the vacation time." We chatted for a bit longer, and then I hung up the phone.
For better or for worse, radio and electronics are never far from my thoughts. So, as I daydreamed about my pending trip, my thoughts wandered to all of the QST articles I'd read concerning DXpeditions and those who travel in order to operate from the remote corners of the earth. I didn't know if Puerto Rico counted as an "exotic" location, or even DX, but I decided that doing a little radio work while I relaxed might be a lot of fun. I wondered if my license would be valid there.
Puerto Rico is a sovereign nation. On the other hand, it's also a commonwealth of the United States. So while Puerto Rico is self-governing, the President of Puerto Rico is in fact the president of the United States, and many U.S. federal agencies like the FCC have jurisdiction there. To confirm this, I shot an e-mail over to the ARRL offices, asking if any special paperwork would be required to operate in Puerto Rico. The answer was no.
My Equipment
My next concern was equipment. While I might have been inspired by DXpeditions, this was not to be one, and there would be no crates of antennas or Pelican cases filled with transceivers. My vision for this trip was casual QRP, running "barefoot" if you will, both figuratively and literally. My equipment choices were governed primarily by the desire to keep my radio activities lightweight and minimalist.
I have a Yaesu FT-817ND, a wonderful QRP rig. From my Arizona QTH, I have worked stations using PSK-31 as far away as New York, and using CW, as far away as Japan. In both cases, my antenna consisted of nothing better than some long wires tossed up into nearby trees. However, as I considered the dollar value of this radio I realized that I wouldn't be comfortable with packing it with my checked luggage. It would have to be part of my carry-on. In addition, while the rig itself is fairly small, adding an antenna tuner and accessories increases the rig's volume to the point that it was more than I was willing to carry. I began to look for alternatives.
Elecraft transceivers are held by many in high regard. Online reviews of their products are uniformly positive, and I've never spoken to an owner of any Elecraft rig who didn't love it. I was attracted to the model K1 for its diminutive size and important options like multiple-band coverage and an internal tuner. Yet, at first glance, Elecraft products were unsuitable for my purposes. My trip was being arranged on short notice and Elecraft radios are kits. It wasn't likely that I'd be able to order a radio kit, receive it, and then build it in time to take with me.
As luck would have it, a search for Elecraft rigs on Ebay turned up a K1 with the four-band option (making it a K1-4), the auto-tuner option, the internal battery option, and the noise blanker board. I bid on the transceiver and won. When the radio arrived, I installed a set of eight "AA" batteries and I connected the rig to a random wire antenna. Forty-meter CW stations streamed in, loud and clear. I removed the antenna and replaced it with a signal generator. Calibration of the receiver's frequency display was a little bit off, but easily corrected. I exchanged the signal generator for a dummy load, and keyed into it. The transmitter waveform looked nice and the calculated output power was about right.
Rummaging through my stock of treasures (my wife calls it “junk”) I found a small, light, foam-lined hard-shell case that had been home to some scrapped piece of test equipment. The K1-4 fit inside perfectly, and the radio with its case fit comfortably inside my carry-on bag.
With a functional vacation rig, I turned my attention to the choice of an appropriate portable antenna. I should mention that I own one of W3FF's Deluxe Buddipole antenna packages. The Buddipole is an effective and well-made piece of equipment consisting of a sturdy aluminum tripod, a telescopic mast, collapsible dipole arms, adjustable loading coils, and odds and ends that knock down and fit into a black nylon bag about 24-inches in length. This package was an obvious antenna candidate for this trip, but in the end, I declined. When I said "minimalist," I meant it. I didn't want to be burdened with another carry-on bag, and as the deluxe Buddipole is anything but cheap, I didn't want to risk having it crushed under a mountain of luggage in the hold an aircraft.
I've had reasonable luck with makeshift wire antennas in the past, and I decided that this would be the course I would follow. What I needed was something to store and manage my antenna wires with. I took a trip to a local sporting goods store in search of camping clotheslines. Both Coleman and Coghlan manufacture inexpensive clothesline reels. These reels, complete with stubby crank handle, are enclosed, and look somewhat like yo-yos. I purchased four of them. In each case I unwound and removed the nylon string inside, replacing it with a light-gauge stranded wire. The wire was cut to give me at least a quarter-wavelength at 40 meters. I think I loaded the spools with 35 to 40 feet of wire, figuring that I could cut away any excess wire as needed. I terminated the free end of the wire with a banana plug. I purchased a small canvas shaving bag, and placed all four reels into the bag.
Finally, I considered accessories for my "station." I located a Pomona BNC-to-banana-jack adapter so that the plugs on my antenna wires could be easily connected to the radio. This went into the canvas bag along with a large package of alkaline "AA" batteries, a small notepad and pen to make log entries, a cheap J-38-copy Morse key, and some miscellaneous cabling, including a few alligator leads. To this I added to pair of cheap Walkman-style headphones. I wanted to bring some tools, but I decided that a full-blown toolkit was overkill, so I purchased a cheap all-in-one pocket tool. Finally, I tossed in a small LED flashlight.
In this post 9-11 world, one can never be sure how a baggage inspector might react to coils of wire and electrical “gadgets” appearing in luggage. To avert any possible problems, I typed up and printed a brief message explaining that I am a radio amateur, and that the items in the bag are for use in conjunction with licensed radio activities. I stapled a copy of my license to the note for good measure, and then placed the documentation in the bag.
An Early Disaster And A Quick Recovery
As the clock ticked away toward the day of our departure, I made some effort to become acquainted with my Elecraft rig. I tried calling CQ to chat with other operators, but I was never successful. I'm not sure what the problem was, it may have been nothing more than poor band conditions. Still, I moved the rig to my workbench and reconnected it to my dummy load, hoping to monitor the transmitter's output. Since "AA" batteries drain fairly quickly, I also wired the radio to my bench top power supply and keyed up the rig.
The radio worked for a moment and then the display went blank. I glanced at the meters on the bench supply. The radio was suddenly drawing more than 4 amps! Holy cow! I immediately shut down the radio and the supply. Something was seriously wrong. Looking into the supply jack with a DMM, I read a near short circuit. Something inside had let go.
Using the Elecraft documentation that came with the radio, I began hunting for the culprit. First, I suspected a failed RF power transistor. I unsoldered it from the radio, but the short persisted. Then, I thought a voltage regulator had self-destructed. Again, I removed it, but the short persisted. Studying the radio's schematics further, I noticed a zener diode that shunts the RF power transistor. I believe the purpose of this diode is to protect the transistor from excessive voltages in the event of high SWR. I removed the offending zener, and the short circuit went away.
I don't know why this zener died. At the time of the failure, the transmitter was connected to a 50-ohm load, so I don't think that excessive SWR was a factor. I did notice one thing, however. My bench supply, while linear, appears to use relays to "step" through voltage ranges. (I'm guessing that this is probably a strategy to minimize power dissipated in the internal pass transistors.) Speculating further, this range-switching behavior might result in brief power interruptions, and it's possible that the K1's RF power circuitry doesn't like this. In any event, I replaced the zener with a new part.
Since the radio was already dismantled, I inspected the work of the person who had built the kit. I saw a lot of what looked like cold solder joints. I spent an hour or so going over the entire radio, refluxing and reflowing connections. I reassembled the radio, and connected it to a different bench supply. Everything worked perfectly.
Ham Radio In San Juan: My First Attempt
A few days later we flew out to San Juan. We arrived at our hotel very late, too late, in fact, for any radio fun. The following evening, while my wife worked on her laptop, I decided it was time to attempt a contact or two.
My antenna consisted of two wires, drawn from my clothesline reels. One wire served as my antenna, and was dangled off the balcony of our 12th floor hotel room. The second wire, lying on the floor, extended from one corner of the room to the other. This was to be my counterpoise. I turned on the rig, tuned to the low end of the 40-meter band and CW flooded in. The situation looked very promising.
I was fumbling with my Morse key and its cable, when I noticed my radio jump across the desk. If I had ignored this warning, the radio no doubt would have flown out the door and over rail. Somebody, a few floors down, had noticed my antenna wire and decided to yank on it! I shouted for the guilty party to let go, and I quickly retrieved my wires. I wound up my antennas, put my equipment away, and resigned myself to radio silence.
Enjoying Puerto Rico
Since this trip was about relaxation, I didn’t let my radio problems get me down. Puerto Rico is a beautiful place to visit, with an ideal climate, great music, great food, and lots of nice people. The landscape is surprisingly diverse. The major highway along the north coast cuts through areas that are green, lush, and rainforest-like. Along the south, I saw arid hills and scrub brush that looked a lot like the landscape at my home QTH in Arizona. Needless to say, the view of the ocean and the Isla Verde Beach behind our hotel in San Juan was breathtaking.
The caves in Camuy are a must-see. Tours take you through cathedral-sized chambers complete with dripping water, stalactites, and astounding mineral formations. The mouth of the cave is draped in jungle vegetation, dangling vines, and carpets of moss. The air is filled with the sounds of birds and the peculiar chirp of the Coqui frog.
Nearby is the famed Arecibo Observatory, an attraction that no self-respecting ham would dare miss. There you can see firsthand the world’s largest antenna dish, a thousand feet across. This antenna has sufficient gain to detect weak signals emitted from objects hundreds of millions of light years away.
Closer to our hotel was old San Juan, and there one can visit two historic forts. El Castillo San Felipe del Morro, the first fort we visited, was built in 1539 by the Spanish. Nearby is Castillo de San Cristóbal, finished in 1783. I highly recommend the forts to anyone with a taste for architecture, history, and scenic views.
My visit to the forts proved beneficial for an unexpected reason. It was there that I stumbled upon the solution to my antenna dilemma.
Finding The Magic Sky Hook
Adjacent the Castillo de San Cristóbal is a large grassy field. At the time of our visit, the area was filled with children and their parents, launching, flying, and tending to kites. There must have been hundreds there. In fact, I have never seen so many kites in the air in one place at one time. As I said earlier, radio and electronics are never far from my mind, so in watching these kites dance on the ocean breeze, I wondered if a kite might not be the solution to my antenna problem.
I located a pharmacy nearby, and for less than five dollars, I purchased two spools of twine and a plastic kite in the shape of a B2 bomber. When we returned to our hotel, I gathered my K1 and my accessory bag and headed out to the beach.
I went to an unoccupied area, attached some twine to my kite and let it go. It leapt into the air. (Winds were reported at 8-9 mph.) When it had risen to a height of twenty or thirty feet, above ground turbulence, I knotted a loop in the line, and used this as an anchor point for my antenna wire. Then, I allowed the kite to rise farther. As it did so, I metered out antenna wire from one of the clothesline spools. When I reached the end of the wire, I tied the kite string to a heavy beach recliner. My little plastic B2 bomber hovered in the sky and had no apparent problem supporting thirty-five or forty feet of stranded wire into the air.
More than once I’ve heard hams speak longingly of a mythical “skyhook” as a solution to their antenna support problems. For all intents and purposes, I had found one, and it worked great.
I used my remaining wire reels to lay out three radials on the beach, and then I hooked up my K1. I hit the auto-tuner, it chattered, and then the display reported an SWR of 1.1. Not too shabby. I plugged in my Morse key and headphones, set the radio to the 20-meter band, and called CQ.
Sadly, I found the 20-meter band choked with QRM, electrical static of some kind. I was able to make brief contact with another operator (which I am still trying to confirm) but I soon lost him in the noise. Despite my lack of success, the kite antenna functioned flawlessly. I packed up my station and hauled down the kite. I decided that I’d wait for sundown to try again.
After a great dinner and an evening of fun, my wife and I headed back out to the beach with my equipment. I was initially concerned that flying a black kite in the dark might be problematic, but my sky hook rose into the air without a hitch. Once more I hooked up my radials, headphone, and key to the K1. On the 40-meter band, the SWR match was 1.2. Signals flooded in. I found a quiet spot in the band and called CQ. This is where all of my efforts finally paid off.
First I worked an operator in Vero Beach, Florida, a distance of about 1100 miles. I’m still waiting for a QSL card on this. On another attempt, I reached Chas, K4HP, in Savannah, Georgia, at a distance of 1300 miles.
My favorite QSO was with Tom, WS9C, in Bloomington, Indiana. Not only was this the greatest distance I’ve yet confirmed, nearly 1900 miles, but it turns out that I had worked Tom from my Arizona QTH some time prior. I think he was amused by my description of my station: my Elecraft, my B2 Bomber kite, and my 10-yard proximity to the pounding surf.
Conclusions
Life is about learning. My conclusions from this experience include:
* Puerto Rico is a great place to visit. I’d like to return someday with the time to see some of the other sights.
* Combining ham radio with a relaxing vacation is pure fun. A casual attitude toward radio keeps things in happy perspective, even if things go wrong. My equipment is definitely going with me next time I travel.
* Sometimes less is more… CW and QRP reign supreme!
* Buying an assembled kit can be an effective way to get great equipment at a good price. However, plan on inspecting the soldering work. Exercise your equipment before taking it on the road.
* Despite what some hams think, modern radios can be diagnosed and repaired in the home shop.
* “AA” batteries are convenient but impractical power sources. Next time, I’ll bring something more robust, and preferentially, rechargeable.
* Simple wire antennas can be very effective, particularly under makeshift conditions.
* A kite in an ocean breeze is the closest thing to an ideal skyhook that the average ham will ever find. Try it!
(This article originally appeared in the ARRL's Feature Articles Section, November 13, 2007)
Document Revision 1, 11/13/07
Document Revision 2, 01/03/08