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In the Field with IPH
December 1931 QST Article

December 1931 QST

December 1931 QST  Cover - RF Cafe[Table of Contents]
These articles are scanned and OCRed from old editions of the ARRL's QST magazine. Here is a list of the QST articles I have already posted. As time permits, I will be glad to scan articles for you. All copyrights (if any) are hereby acknowledged.
It is hard to imagine a time when there wasn't a vast network of highways connecting not just the interior of the continental U.S., but also interconnecting all of the countries in North America. Just as pioneers in covered wagons and on horseback forged the routes that became the Oregon Trail in the early 19th century, so did teams of explorers, cartographers and engineers do the heavy lifting in the early 20th century in establishing the first defined roads for expediting the transportation of goods and persons all up and down the continent's west coast. Radio operators were among the crews of the International Pacific Highway (IPH) project. Heavy, bulky, and fragile tube-based radio equipment was transported in vehicles equally bereft of adequate facilities in the form of power and shock absorbing suspensions. This story from a 1931 edition of the ARRL's QST magazine tells of harrowing experiences in the jungles and mountains of South America, including very aggressive natives and even bands of roving banditos. Reading the story conjures up thoughts of The Treasure of the Sierra Madre and famous "I don't have to show you any stinking badges" line. Zepp antennas were the order of the day for successful QSOs in just about any environment.

See all available vintage QST articles.



In the Field with IPH


By Bertram Sandham, W6VO


The author keeping the radio car from starting back down the mountain - RF Cafe
The author (extreme left) keeping the radio car from starting back down the mountain as a bunch of Indians turn it around.



Working a W9 with woolen gloves in extreme cold at an elevation of 10,000 feet - RF Cafe
Photo by C. W. Martin, Los Angeles Times
Like shelling peas: Working a W9 with woolen gloves in extreme cold at an elevation of 10,000 feet.



Weeks were spent cutting tracks for the expedition in jungles such as this - RF Cafe
Weeks were spent cutting tracks for the expedition in jungles such as this.
What a vicious look we gave those rugged and forbidding mountains that lay to the leeward of the French liner as its bow tossed the miles aside between Los Angeles harbor and EI Salvador. Beautiful indeed with its cities buried in the mists of antiquity, but what an obstacle it all offered to the progress of our expedition I I chose to have my cabin on the weather side of the vessel.

The first expedition which set out last year to explore the tentative route for the International Pacific Highway, which will ultimately reach from Alaska to Buenos Aires in Argentine, had sufficient troubles making progress over the ox-cart trails and boulder strewn terrain, but it now seems a pleasant vacation trip when paralleled with the vicissitudes that the party encountered on the second expedition which began its trek from Mexico City January 25th and ended at La Libertad, EI Salvador, May 1st.

The radio layout on this second trip was a vast improvement over that of the first - at least in the physical make-up and added convenience. As was the case with the first expedition, little advance notice was given for preparation for the journey. The equipment was finished and installed only a few hours before the expedition departed, and IPH was not on the air until we were in the field. On the extreme right in the photograph is the transmitter, a 50-watt tube in a t.p.t.g. circuit. The power supply rests in its bin in the upper left hand corner and is one of the new products of Ralph Heintz' genius. This engine generator unit furnishes 52 volts at 350 cycles as well as 10 volts for the filament. This 400 watt machine is driven by a two cycle single cylinder engine and runs as high as 4000 r.p.m. The unit weighs but 31 pounds complete. Below the engine compartment is the frequency meter, and to the right of this the receiver using three N tubes. The other compartments carry coils, vibroplex and other parts. Forty and twenty meter Zepps were carried on a reel and hung to anything that offered a support. Sometimes a tall building in a city offered an almost vertical antenna while at other QRA's it was impossible to suspend it higher than ten feet above ground; but it seemed to get out just as well even so.

The infernal inquisitiveness of the natives is the biggest bugaboo for the operator on such a trip as this. The radio car must be near a street or road in the city and its array of instruments quickly gathers the dark-skinned lads and men who are nearby, while the racket made by the engine thoroughly advertises the QRA to those not nearby and they come running like magic. At Tehuantepec, in southern Mexico, some ambitious fellow started the game of "tapping." This consisted of tapping someone else in the crowd and quickly withdrawing the hand while the victim looked around in amazement to learn who had struck him. The progress of this game grew like a sunflower with everyone tapping someone else harder as time progressed. In a few moments they were falling all over the radio car bumping against me as I was QSO a W9. A member of the party happened by and came to my assistance by rushing to the mayor's office and returning with soldiers. The excitement even brought the Mexican federal inspector to the scene who asked to see my permit for using a radio transmitter in Mexico. Following the QSO I had to conduct him to our hotel where among a ream of permits for motion pictures, firearms and what not, I showed him the paper permitting the radio work. He read this and left in great disappointment thinking that he was indeed about to make a big haul.

While camped for the night in a dense jungle we had no other choice than to camp with a forest single fire as our next door neighbor. This burned slowly however, consuming dried leaves and dead trees. A dead tree nearby was silently burning inside (unknown to us) and suddenly, as I was QSO W9EUU, the tree toppled over missing the radio car by several yards and filling the air with ashes and smoke that made the completion of the QSO a very difficult task.

After departing from the city of Juchitan, we were proceeding slowly over a narrow sunken ox-cart trail that was grinding the rubber off the tires like an emery wheel. A guide whom we had employed in this city rode in the first car with the engineer. The cars were running about 300 feet apart due to the dense dust when suddenly the guide appeared through a dust cloud holding his revolver in his hand and running back toward the city as fast as "his feet would carry him. He shouted "Hold-up" in Spanish as he passed our car. I stopped instantly and started to open a compartment for my pistol when my riding companion shouted to leave it there as we were covered. The brush along the road was filled with rebel bandits with rifles and bandoliers of ammunition. We were ordered to drive up to the other cars where the leader was ordering them looted. Our interpreter however, talked with the leader at length, and we were fortunate to lose only a few articles which the bandits were in immediate need of. These consisted of a case of sardines, flashlights, ammunition, cigarettes, matches, etc. I was thankful no part of the radio equipment was taken for the reason that I might have to remain behind to teach "his nibs" the code. Some of the members of the expedition were hazarding the thought that the bandits might follow us and attack again while we were in camp. I added that they surely would if they ate any of the sardines in the meantime. These we had purchased in Tehuantepec and they were terrible. Our camp that night was made with a minimum of equipment and we slept with our clothes on.

IPH was not on the air daily as on the first expedition. QSO's were had from the principal cities and camps, but more amateurs were contacted than on the previous trip. Very favorable signal reports were usually given, IPH being rarely less than R6, several adding that the sigs compared favorably with those of XDA. All districts except sixth and seventh were heard each time on the air. The hours available for radio work seemed to be those when west coast signal were not coming through.

Operating a radio transmitter on this type of an expedition, where there is a different QRA nearly every day, is not what it is cracked up to be. In the jungle it is no easy task to keep the car near camp and also have the Zepp hanging in a reasonably clear space. The best tree was usually on the other side of the river, necessitating the use of hip boots. In the small villages there were but one story buildings. In the deep canyons, heavy mineralized cliffs reduced signals to a whisper. The exhaust of the engine usually prohibited copying signals that were less than R5 although the engine was placed on the opposite side of the car at the end of a 25 foot cable. Added to this, the operator drove the radio car - I mean tried to drive it. Boulders half the size of the car covered the path, while the sides of mountains had to be scaled with 40 Indians pulling on a tow rope. Then we had to wash our own clothes, put up and dismantle camp, work on the cars, etc. A mosquito head net was necessary while QSO on the transmitter as well as oil being rubbed on the back of the hands and neck. A small fire was also kept running to keep the mosquitos, gnats and a thousand other varieties of bugs at bay.

Skip and fading were continuously bad. Daily business was left hanging on the hook many times due to this annoyance. One member of the expedition interested himself with this phenomena and concluded that if the flat top of the Zepp had an acute bend in it, the signals would be sent out in such a ghastly form that Mr. Skip would hide when he saw them coming. To keep peace in camp the Zepp was hung the following day with an acute hump in it, and lo! sigs were R8 and no skip. This was no break for me. I had to tell him that it was worse than ever.
 
About 15 miles were driven along the railroad right of way over mahogany ties that were anything but straight. More than a dozen railroad bridges were utilized to cross rivers too deep for fording. The brakes on one of the cars locked as it endeavored to climb up over the rails onto the bed with a train due in 15 minutes. The mechanic hurriedly disconnected all of the brake rods but not before the train came hustling down the line. It stopped within a few feet of the car while the engineer shook his fist from the cab window.

The passage of the cars from the city of Oaxaca to Tehuantepec, a distance of seventy miles, consumed fifty days, the party working every day including Sunday to move the cars over the 40 percent grades in the mountains. The Tehuantepec River was crossed 88 times in 17 miles, about every third crossing requiring block and tackle.

Rain governs the length of time that the expedition can remain in the field. Rains began falling when we entered the republic of El Salvador so we headed for the nearest port (La Libertad) and the cars were lightered out to the vessel and we headed for home. A torrential downpour caught us high in the mountains among the coffee plantations and, even though we used chains, the day will remain indelible in my memory. Using low gear as a brake down a steep grade the front wheels refused to respond to the steering wheel as I came to a curve. The front wheels went over the cliff while the right rear fender struck a coffee tree tearing the fender away from the running board but holding the car back from a 1500 foot dive down to the river.

The political situations in Honduras and Nicaragua will strongly govern the plans of the expedition for the third trip, which normally would depart again next January to pick up the thread of the trail at El Salvador and proceed to Panama if possible. Several hundred miles of jungle in Costa Rica must be progressed through which there is not a vestige of a trail today.

Radio conditions for short wave transmission and reception between southern Mexico or Central America and the Sixth U. S. District during our spring months is atrocious. It proved so on this trip. An occasional QSO of the usual variety was sandwiched in several times, but to get several hundred words of press for newspapers and other messages off the hook daily is out of the question. Several operators in the sixth district have related to me since my return to civilization that they had heard operators in the ninth district give IPH R7 and R8 copying me single, but the sixes in question were unable to hear my signals at all, hunt and twist the dial as they might even though they knew I was on the air at the moment. However, there was not a single exception encountered when an amateur was contacted that he did not stand ready to take press and other messages and forward them. Many, no doubt, did not handle traffic as a general rule but all were ready to help IPH. One cannot realize what this means until buried in the jungles or high in the barren mountains in terrific heat and has the amateurs to depend upon to move the business. I want to offer my sincere thanks to all of them. Here are the stations with which successful contacts were made: W9BPL W6EW W6DK W4AEV W8BOJ W9UM W8BJX W9CES W5BOL W2AHZ W1KM W8BUM W1ZZ OA4V W4AEM W4AJD W4LM W8DNO W7AAT W5AB W6CYR W8ANO YN2XUF W5YW W6EPH W5AGG W4AEL W4ABS W4BC W2BO NJ2PA W4SR TI3XA W9YL W5CE W6BKL W6DZD W6AHP W5HA W5VQ CM1BY W9ID W4AKH W8BF W3JM W5QL W8BF W5LB W2BAK W2AHZ W9ETA W9EUU W4ALD W2DB W9DFT CM1EM.




Posted  12/18/2012

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