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DIGEST OF ARTICLES -- QST December, 1993 Following are digests of articles printed in the December, 1993 issue of QST. Such digests are being prepared for each issue of QST, and posted periodically. Subsequent issues will be posted one per week until they "catch up" to the current date in mid-1994, thereafter monthly. It is hoped that other hams will volunteer to post similar digests of the other ham technical publications such as QEX, CQ, 73, COMMUNICATIONS QUARTERLY, RTTY JOURNAL, et al. Especially desirable would be digests of publications in other countries, such as the RSGB RADIO COMMUNICA- TIONS and ham magazines in Europe, Japan, Australia, and other countries around the world. We English speakers would especially enjoy them if they were translated into our language, but they would also be valuable additions to the world's knowledge if they were posted in the language of origin. Who knows? Some bi-lingual ham somewhere might translate them into English and re-post them. Worldwide communications are getting better and better. The time has come to make the world's ham press available to all hams throughout the world! The major value of digests is to give readers sufficient information to decide whether to obtain a copy of the full text. If any U.S. reader wants a copy of an article in QST, please inquire of other hams in your own neighborhood. Many have collections of back issues. Anyone who is unsuccessful in finding a fellow ham with a collection should try every library in the area, especially those at universities and technical colleges. If all else fails, a copy can be obtained from the ARRL Technical Department, 225 Main St., Newington, CT 06111-1494 USA for a fee of $3.00 per copy. Remember, it is both cheaper and quicker to obtain one locally. Readers in most other countries can obtain copies from their own national ham organizations, sometimes translated into their own languages. -------------------------------CUT HERE--------------------------------- COPYRIGHT NOTICE: Copyright to all the following material from QST Magazine is held by the American Radio Relay League (ARRL), effective on the date of issue. Permission is granted for redistribution of the following in its entirety, or in part, provided that this copyright notice is not removed or altered and that proper attribution is made to ARRL as publisher of QST, to the authors of the original articles, and to W. E. "Van" Van Horne, W8UOF, author of this compilation. _________ TABLE OF CONTENTS (line number in parentheses - counting from CUT HERE line) TECHNICAL ARTICLES (TA) TA1:Taking the Mystery Out of Diode Double-Balanced Mixers (67) TA2:Measuring and Compensating Oscillator Frequency Drift (117) TA3:Computer-Controlled Electronic Test Equipment - Part 1 (160) TA4:An Automated Mobile Radio-Direction-Finding System (212) PRODUCT REVIEW (PR) PR1:The Ten-Tec Scout Model 555 MF/HF Transceiver (296) PR2:QST Compares Packet TNCs (382) HINTS AND KINKS (HK) HK1:Is Your Radio Equipment REALLY Grounded? (431) HK2:Audio Patch Cords and RF (451) HK3:Tool Pouch Holds Hand-Held Transceivers (462) HK4:How About NOT Using a 555? (475) HK5:A Fix for Faded Blue-Green Drake Dial Lighting (483) TECHNICAL CORRESPONDENCE (TC) TC1:FAX480 Updates (500) TC2:Automobile RFI Solved (518) LAB NOTES (LN) LN:Satellite-Tracking Software (552) NEW HAM COMPANION (NHC) NHC1:The Frequency and Deviation Conspiracy (589) NHC2:HF Mobiling - Taking it to the Streets (611) NHC3:The Lure of the Ladder Line (626) NHC4:Radio and Railfanning (645) NHC5:The Doctor is IN (668) NHC6:The Joys of FM Simplex (690) GENERAL INTEREST ARTICLES (GI) GI1:Heroics in the Heartland (716) GI2:Eritrea: A Nation Reborn (737) GI3:A Cold Season (768) GI4:The First VHF Contest from Cuba (783) GI5:Gatti-Hallicrafters: The First Grand Ham DXpedition (803) GI6:Ham and Former Ham Share 1993 Nobel Prize (838) ------------------------------------------------------------------------ TECHNICAL ARTICLES (TA) Title>TA1Taking the Mystery Out of Diode Double-Balanced Mixers Author>Joshi, Shankar Source>QST Dec 93, pp. 32-35 Abstract>Description of double-balanced and double-double-balanced diode mixers, their advantages, and how they are used. Also a review of representative available integrated-circuit mixers usable at frequencies up to 35 GHz. Digest>Mixers are commonly used in radio equipment to convert signals from one band of frequencies to another through heterodyning. A simple mixer in a superheterodyne receiver accepts an input signal and a local-oscillator signal; its output is an intermediate-frequency (i.f.) signal. But this output also includes the original two input signals, plus various harmonics and beat frequencies. The local-oscillator signal is the highest amplitude of any signal present. For this reason, the balanced-mixer was developed to balance it out. The double-balanced mixer takes it one step further and also balances out the original signal input. Consequently, to a first-order approximation, the output of a double-balanced mixer is the i.f. signal only. Actually, all the other, unwanted, signals are still present but reduced by orders of magnitude. In this article, Mr. Joshi explains the design and application of the most advanced types of double-balanced mixers available today. The heart of the DBM is a diode ring, or bridge circuit, comprised of four Schottky diodes formed in a single integrated circuit. The input and local-oscillator signals are both applied in balanced form, each taken from the secondary of a center-tapped ferrite toroidal transformer. The output of the circuit is typically taken between the center taps of the two input transformers, in unbalanced form. The author describes the characteristics of each of the major components in considerable detail. A table lists the parameters of ten representative types of Schottky diodes which are rated for operation at maximum frequencies that range from 4 GHz. to 35 GHz, depending upon model number! He further describes the double-double-balanced mixer (DDBM). Thus is a circuit that takes the balancing process another step. It uses two Schottky quad-diode rings, each fed by a pair of toroidal transformers. It tends to balance out the distortion products even more thoroughly than the single DBM. It also offers better signal-handling capabilities and higher isolation between the inputs and the output. DBMs are available as either discrete components or packaged complete circuits including transformers, as well as ring diodes, in single cans. _________ Title>TA2:Measuring and Compensating Oscillator Frequency Drift Author>Hayward, Wes - W7ZOI Source>QST Dec 93, pp. 37-41 Abstract>A description of a controlled temperature chamber and its use in determining the frequency vs. temperature characteristic of oscillators. Also describes temperature compensation circuits and how to adjust them using the chamber. Digest>In this day when much amateur radio gear uses synthesized frequency determination, there is still a place for analog oscillators of the time-honored Hartley, Colpitts, and other classic designs. All of these show some amount of frequency drift, primarily due to temperature changes. The author describes the construction of a simple controlled-temperature chamber that can be used to measure the temperature-versus-frequency characteristic of oscillators. By using it, one can design and insert temperature compensation into the oscillator circuit. The author built his temperature chamber out of flake-board and styrofoam. For a heating element, he uses a light bulb. A thermometer continuously measures the inside temperature. Also included is an exhaust fan that can be used to exhaust hot air and draw in outside air when rapid cooling is desired. He suggests that another fan be placed inside the chamber to stir the air and insure that the temperature is uniform throughout. Mr. Hayward describes his experiences in measuring and developing temperature-compensation circuitry for two oscillators. His recommended approach is that first, every attempt be made to make the frequency-determining components, especially the coil and capacitor of the oscillator tank circuit, to be as thermally stable as possible. Then, when the exact relationship between temperature and frequency is experimentally established, a capacitor with a negative temperature-coefficient can be used to offset the measured drift and reduce it nearly to zero. He shows how the required size of such a capacitor is calculated. In his final summary, the author concludes: "You can have 'rock stable' oscillators if you're willing to build and apply some simple measurement gear". _________ Title>TA3:Computer-Controlled Electronic Test Equipment - Part 1 Author>Portugal, Ron Source>QST Dec 93, pp. 42-50 Abstract>First installment of construction articles for computer-based bench instruments. This one covers the microprocessor board that will be used as the base for the instruments to come. Digest>Most hams today seem to have computers in their shacks, or are contemplating them. They are frequently used for keeping logs, filling out QSL cards, and for operating in the ham digital modes: RTTY, Packet, PACTOR, etc. This article adds one more use for the station computer. It can be used as a control center for test equipment. As such, it will operate as the power supply, provide the control logic, record the data, display the results either as numbers or graphs, and provide a base on which relatively inexpensive, very effective bench equipment can be home-built. In this first installment, Mr. Portugal describes, and provides construction details for, building the microprocessor board that will become the first building block of the array of test instruments. It utilizes a Zilog Z-8671 microcomputer chip. That chip contains an RS-232 serial port in addition to its general purpose central processing unit (CPU). All communications between it and the main computer are through the RS-232 port. The Zilog chip is designed for use as a controller and is popular because of its ease of use. All programming is done in the Basic language. Many of its functions are preprogrammed when the chip is manufactured. The author plans, in future installments, to give full construction details for building the following items: 1. Completely monitored, triple-section power supply. 2. Inductance/capacitance (L/C) meter. 3. 1-Hz. to 10-MHz. frequency-synthesized sine/square-wave generator. 4. 500-MHz. frequency counter. 5. Provision for additional instruments to be added in the future. He indicates that all of these pieces of equipment can be built for costs ranging from $50.00 to $150.00 each. A complete kit of parts for the microcomputer board, also including the Zilog Technical Manual, is available from Ronald J. Portugal, 52 Susan Lane, North Haven, CT 06473 for $150.00 plus $4.00 for domestic shipping. _________ Title>TA4:An Automated Mobile Radio-Direction-Finding System Author>Flanagan, Robert H. - KA1RBH and Calabrese, Louis A., Jr. - N1LZD Source>QST Dec 93, pp. 51-55 Abstract>Describes an automated RDF system built into an automobile. It calculates bearings automatically. The only human action required to find a hidden transmitter is to plot the bearings on an accurate map. Digest>The authors describe a very sophisticated radio-direction-finding (RDF) system built into an automobile. They state that such a system "currently costs well into four figures...." so is not for widespread amateur use, but it is described for general background information. The system is assembled from a number of components, each of which represents a recent development in technology. The bearing of a radio signal in relation to the body of the vehicle is measured by a Doppler RDF unit that uses four vertical quarter-wave antennas mounted on the roof. To convert the relative bearing to a true compass bearing requires that the heading of the vehicle be measured accurately. This is done using a flux-gate compass. Then the absolute location of the vehicle must be known and located on a detailed map. The precise location is measured by a global-positioning system (GPS) receiver. This is the satellite-based measuring system that was developed by the U.S. Defense Department and has only recently been released for civilian use. Finally, bearings taken from the vehicle at two or more locations must be plotted in relation to an accurate map to determine the location of the transmitter being sought. This is done on a laptop computer that automatically locates the intersection of two or more bearings in relation to the United States Geodetic Survey (USGS) Universal Transverse Mercator (UTM) grid. That grid covers the entire U.S. with squares, 1 km. on a side, which are plotted on very detailed topographical maps. Once the computer shows the exact location of the transmitter in relation to the grid, it is easy to find it on the appropriate USGS map. The computer program that accepts the data from the RDF unit, the compass, and the GPS receiver, processes them, and displays the bearings on a grid, was written by the authors. Copies are available from Mr. Flanagan, KA1RBH. One practical problem that the authors had to overcome in the operation of the system was the fact that signals are received not only directly from the transmitter but also by reflection from buildings, cars, metal poles, and a myriad of other objects common in residential areas. The system must sort out the direct signals and ignore the reflected ones. In order to eliminate most of the stray signals, the program accumulates bearings for one minute at a time, selects the angle from which the largest number of bearings was detected, and rejects any that were more than 15-degrees from that angle. Then it averages all the bearings within that angle to report the most probable direct bearing. As the car moves, more and more bearings are calculated and, as the vehicle gets closer, the uncertainty of position becomes smaller and smaller. The authors describe two improvements that they would like to add to the system. First, it would be a great convenience to be able to display a highly detailed map on the computer screen with the grid squares and plotted bearings superimposed so that they could dispense with the cumbersome paper maps. Second, they are considering using packet radio to interconnect all the "hunters" in a foxhunt so that all participants would have the benefit of the bearings taken by the others. The result would be: "Working as a group, we could watch our bearings zeroing in as our screen display is updated automatically. Even the fox could get in on the action and watch our progress!" They did not address the question of whether this would defeat the purpose of the foxhunt! The authors report that they have utilized their automated system in several foxhunts and have found it to be a "great tool" because it is "fast, accurate, and allows the operator to concentrate on other activities, such as driving and picking the next location for a bearing." ------------------------------------------------------------------------ PRODUCT REVIEW (PR) conductor: Mark Wilson, AA2Z Editor, QST _________ Title>PR1:The Ten-Tec Scout Model 555 MF/HF Transceiver Author>Newkirk, David - WJ1Z Source>QST Dec 93, pp. 77-80 Abstract>A review of the least expensive, nearly full-function HF transceiver now on the market. Digest>The Ten-Tec Scout is a highly innovative new transceiver that offers good performance on all bands from 1.8 to 29.0 MHz. It features 50-watts output, very small size, a built-in keyer, and an ultra-low price! One of the ways that Ten-Tec has kept the price down involves the method of band changing. There are no bandswitch and built-in multi-band components!. Instead, a separate module for each band must be plugged into a front- panel receptacle. The listed price of $495.00 is actually for a single-band receiver; each additional band requires the purchase of a module for $25.00. Reminiscent of the famous National HRO receivers of 40 or more years ago, the plug-in modules can be considered either an advantage or a drawback, depending upon one's point of view. For one thing, buyers do not have to pay for bands they do not intend to use. Also, one can make an argument that plug-in coils can be more efficient than the bandswitched variety. On the other hand, if one buys a full complement of 8 extra plug-in modules, the additional $200.00 makes a total price not far below that of competitive rigs. In the process of keeping both the physical size and also the price small, Ten-Tec has made some compromises. For one thing, the frequency-determining circuit is a permeability-tuned oscillator, not a synthesizer. Like all oscillators, this one is subject to some drift as well as step changes caused by physical jarring. But the drift is not a big problem, for two reasons: First, the rig contains a frequency counter that displays the actual frequency; and second, the frequency-counting software detects the drift and counters it automatically! These compensating actions are not instantaneous, however, and both the operators and others in QSO with them can detect the frequency changes as they occur. The Scout's small front panel contains only 5 knobs: tuning, audio gain, i.f. bandwidth, offset tuning (RIT), and microphone gain. In addition, there are three switches, two jacks, a four-digit frequency display, 1 LED indicator, and a meter. The switches are: (1) a 3-position Tune-Off-Noise Blanker. In the Tune position, the transmitter emits a low-power signal (CW) for antenna adjustment. The Noise Blanker activates the impulse-noise limiter circuit. (2) Speed-Off-RIT. In the Speed position, it allows one to adjust the speed of the internal keyer upward or downward by pressing the dot or dash paddles; the RIT position turns on the receiver offset tuning. (3) Power (on-off). The two jacks are for a microphone and for audio output to speaker or headphones. The meter displays signal strength while receiving, and either output or SWR while transmitting. The single LED indicator, "ALC", indicates when the automatic level control is operating during transmission. During single-sideband operation, the appropriate sideband is selected automatically by the band module in use. It is not possible to reverse sidebands. The reviewer operated the rig and paid special attention to the receiver, since it is in the receive function that most inexpensive transceivers show their limitations. He was pleasantly surprised at the Scout's performance. It uses a single i.f. at 6144 KHz., so image rejection is not as complete as with the latest top-of-the-line transceivers, but the images are unlikely to cause any real problem except under unusual operating conditions. I.f. filtering is done by multiple-crystal filters. On CW, the reviewer found the selectivity to be "acceptably good - it suitably knocks down the CW audio image even with i.f. bandwidth at its widest setting". In transmitting, on CW the keying is excellent and the rig always operates full break-in. Its switching time is fast enough even for AMTOR operation. On SSB, its audio is good. The AGC operation is a compromise between SSB and CW; it uses a fast attack and slow decay. The reviewer found its operation to be "first rate". His final conclusion was: "I like the Scout.... Its simple controls and straightforward operation put a minimum of mechanism between me and the stations I want to work." _________ Title>PR2:QST Compares Packet TNCs Author>Ford, Steve - WB8IMY Source>QST Dec 93, pp. 80-81 Abstract>A review of five current terminal-node controllers for packet only. Included are units built by Kantronics, DRSI, MFJ, AEA, and PacComm, all priced between $100 and $150. Digest>Two-meter packet is the most popular digital mode in ham radio today. There are several reasons for this. For one, the advent of "no-code" licenses means that the majority of new hams head for VHF. Anyone with a computer and a 2-meter rig, even a hand-held, can get onto Packet easily and at relatively low cost. More importantly, packet is an exciting mode. Lots of new things are happening, networks are rapidly expanding, high-speed trunk lines are criss-crossing the countryside, and digital technology naturally appeals to a great many hams. For a ham who already has a computer and a 2-meter station, the only added equipment he needs to get onto packet is a terminal-node controller (TNC). Of course, one can use an expensive multi-mode communications processor (MCP) that provides a wide variety of operating modes in addition to packet, at a correspondingly high price. But if one is interested only in VHF packet, a late-model packet TNC can be bought for a list price ranging from about $115.00 to $150.00. This article reviews five such models now on the market. The 5 units reviewed are the Kantronics KPC-3, the DRSI Model DPK-2, the MFJ Model 1270B, the AEA Model PK-88, and the PacComm Tiny-2 Mark II. All five of these provide the most basic features: Mailbox, KISS mode, and Host mode operations. All but the DRSI DPK-2 also provide automatic mail handling, so that one can make arrangements with their local packet bulletin-board system (PBBS) and leave the receiver on continuously. Then, any mail that is received by the PBBS will be automatically forwarded to one's own computer. The selection between the 5 models will probably hinge on what other features besides those listed above are of interest to the buyer. Other items to be considered are: whether one is also interested in packet on the HF bands; receiving weather maps by facsimile; 100-percent compatibility with the original Tucson Amateur Packet Radio (TAPR) Model TNC-2; whether software is included; and other factors. ------------------------------------------------------------------------ HINTS & KINKS (HK) conductor: David Newkirk, WJ1Z Sr. Asst. Technical Editor _________ Title>HK1:Is Your Radio Equipment REALLY Grounded? Author>Cardwell, Martin L. - NB3T Source>QST Dec 93, p. 85 Abstract>How to assure a low-resistance ground connection. Digest>The writer had his common ground point in the shack grounded to a rod driven into the earth. His beam antenna was likewise connected to a ground rod at the base of the tower. In an attempt to trouble-shoot QRN, he found that there was very high resistance between the two ground rods, indicating that either, or both, had very high contact resistance with "true ground". To cure the problem, he replaced his old ground rods with pure copper tubing. Now he measures between 10- and 15-ohms between the two rods that are some 45-feet apart. He intends to monitor this resistance periodically to ensure that the ground connections will continue to have low resistance in the future. _________ Title>HK2:Audio Patch Cords and RF Author>Swynar, Edward "Eddy" Peter, VE3CUI Source>QST Dec 93, p. 85 Abstract>Use r.f. coax, not audio patch cords, for rf! Digest>Mr. Swynar cautions all hams not to use audio patch cords for r.f. since the audio shield is not a good r.f. shield. Use coaxial cable designed for radio use. _________ Title>HK3:Tool Pouch Holds Hand-Held Transceiver Author>Hendrey, Bill - KC6JGS Source>QST Dec 93, p. 85 Abstract>A holster available at hardware stores just fits the ICOM IC-24AT hand-held transceiver. Digest>Mr. Hendrey points out that a Skil holster, which is designed to hang from one's belt and carry a Skil tool, exactly fits the ICOM IC-24AT hand-held transceiver. The stock number designation of the pouch is "Twist Pouch No. 92160", available at hardware stores. _________ Title>HK4:How About NOT Using a 555? Author>Newkirk, David - WJ1Z Source>QST Dec 93, pp. 85-86 Abstract>Suggests using an LM322 or LM3905, instead of a 555, timer chip in the 10-minute timer circuit described by Conklin in HK, QST Nov 93. _________ Title>HK4:A Fix for Faded Blue-Green Drake Dial Lighting Author>Ross, Arnold J. - W2NXC Source>QST Dec 93, p. 86 Abstract>When the color fades from light bulbs, paint them with nail polish. Digest>The writer notes that the dial lights on Drake ham equipment which are blue-green when new, fade in time. He recommends restoring the original tint by painting the bulbs with blue nail polish, Artmatic USA No. 163 Peacock Blue Nail Enamel, bought at K-Mart. ----------------------------------------------------------------------- TECHNICAL CORRESPONDENCE (TC) conductor: Paul Pagel, N1FB _________ Title:TC1:FAX480 Updates Author>Taggart, Ralph - WB8DQT Source>QST Dec 93, pp. 87-88 Abstract>Describes improved software for slow-scan TV and FAX. Digest>This letter is of interest to hams who are involved in slow-scan TV (SSTV) and FAX video modes. The writer is the author of the FAX480 software that provides an operating program for FAX and SSTV transmission and reception. In his letter, Mr. Taggart discusses the details of his latest upgrade, known as FAX484/FAX481P. The new upgrade improves the loading of images into memory, simplifies a manual restart, and provides a better method of overcoming problems caused by noise or QRM interrupting the reception of an image. _________ Title>TC2:Automobile RFI Solved Author>Zak, Stan - K2SJO Source>QST Dec 93, p. 88 Abstract>Toyota driver corrects RFI problem after receiving no help from the manufacturer. Digest>The writer reports problems that developed when he installed a Kenwood VHF transceiver in his 1993 Toyota Camray. When he transmitted at full 50-watts output, a dashboard warning light indicated that the taillight had failed. He followed of Toyota's recommendations to solve the problem, without success. He finally solved it by shielding the rear-window brake-light assembly with a grounded-wire screen. The screen did not affect the brightness of the light. Ed Hare, KA1CV, ARRL Laboratory Supervisor, appended a comment to the letter. He reports that he had contacted the Toyota Technical Department about frequent problems reported by hams who had installed transceivers in their automobiles. He was assured that transmitters running up to 100-watts should have no problems with Toyota vehicles. The fact that Mr. Zak got no help from the manufacturer but was able to find such a simple solution to his problem shows that Toyota has not spent the engineering time required to solve such trivial problems. It seems that their assurances have little value. Mr. Hare is accumulating such reports and intends to keep pressing recalcitrant manufacturers to obtain meaningful help. ------------------------------------------------------------------------ LAB NOTES (LN) conductor: Steve Ford, WB8IMY Asst. Technical Editor _________ Title>LN1:Satellite-Tracking Software Author>Ford, Steve - WB8IMY Source>QST Dec 93, pp. 89-90 Abstract>Describes satellite-tracking software, what it does, and how to use it. Digest>This month, Mr. Ford has prepared, in Question and Answer format, a description of satellite-tracking programs and what they do. The function of such software is to tell the user when a particular satellite will appear above the horizon, and specify its exact postion continuously as it passes overhead. To do this, the computer must be given the latitude, longitude, and elevation above sea level of the ham station. It also must be given the orbital elements of each satellite. Orbital elements are sets of numbers used to describe the orbit of a satellite. They can be obtained from various bulletin boards, both via telephone and packet radio. They must be updated periodically since orbits change slowly with time. Various software packages offer different features. In many cases, they display maps that plot the satellite at all times. Some programs also provide control outputs that can be used with antenna mounts that are motorized in both azimuth and elevation to position the antenna automatically and follow the satellite as it passes overhead. The article lists the name and address of five different sources of appropriate software. ------------------------------------------------------------------------ NEW HAM COMPANION (NHC) The New Ham Companion is a regular monthly section in QST that concentrates on articles of primary interest to newcomers to ham radio. _________ Title>NHC1:The Frequency and Deviation Conspiracy Author>Leahy, Bill - K0ZL Source>QST Dec 93, p. 66 Abstract>Why it is necessary that FM frequency and deviation be carefully adjusted, and how to do it. Digest>The author explains what frequency and deviation mean in frequency-modulated (FM) transmissions, how important it is that they be adjusted properly, and how to go about such adjustment. Especially when working through a repeater, it is necessary to adjust the frequency of the rig to within about 0.2-KHz. of nominal and also to adjust the deviation to a total of 5-KHz. If the repeater requires a continuous tone-coded squelch system (CTCSS) tone, then the deviation must be reduced to about 4.5 KHz. to allow for the addition of the tone. If both frequency and deviation are not properly set, it is probable that the signal will be "chopping" in and out of the repeater because, on voice peaks, the carrier energy is outside the passband of the repeater's receiver. _________ Title>NHC2:HF Mobiling - Taking it to the Streets Author>Gold, Jeff - AC4HF Source>QST Dec 93, pp. 67-69 Abstract>Describes operating HF mobile from an automobile and suggests some suitable equipment. Digest>Mr. Gold describes his enthusiasm for operating mobile on the HF bands from his automobile. Then he describes a number of commercial antennas and also small-size transceivers handy for mounting in or under the dashboard. He points out that almost any kind of HF operating can be done from a vehicle, including nets, DXing, contesting, digital-mode operating, rag chewing, and QRP operating. _________ Title>NHC3:The Lure of the Ladder Line Author>Ford, Steve - WB8IMY Source>QST Dec 93, pp. 70-71 Abstract>The advantages of open-wire line for feeding a dipole. Digest>Mr. Ford describes the advantages of feeding a multi-band dipole with balanced open-wire line, as opposed to coax. He relates his own experience when he converted from coax to 450-ohm ladder line and achieved much better performance. He largely refutes the common fears of problems arising from using open-wire line near metal. He relates advice that he received to the effect that crossing a metal window-sill at right angles, for example, is no cause for worry so long as there is not an actual metal-to-metal contact. Also that ladder-line can be run within a few inches of even large masses of metal, such as aluminum siding, so long as a separation of a few inches is maintained. _________ Title>NHC4:Radio and Railfanning Author>Clark, Brad - NP4AI Source>QST Dec 93, pp. 72-75 Abstract>Activities of railfans and how they use ham radio in them. Digest>There are a large number of people who call themselves railfans and are interested in all aspects of railroad operation. Most are especially interested in the historical aspects, including steam engines and any tools and equipment dating from the era of steam. Recent laws making mobile use of radio scanners illegal to most people have led a number of railfans to earn ham radio licenses, because hams are explicitly allowed to use mobile scanning equipment. With a ham license, they can not only monitor traffic regarding rail operations but they can also use VHF/UHF HTs to keep in contact with other fans on an outing. The author describes organized activities carried on by railfans, includes hints of how to enjoy them, and cautions against unsafe, discourteous, or illegal activities. _________ Title>NHC5:The Doctor is IN Author>Various Source>QST Dec 93, p. 76 Abstract>Questions and answers for ham newcomers. Digest>This is a regular monthly feature in the New Ham Companion section. It is a series of questions and answers of special interest to newcomers. In this month's column, questions discussed were ways to route the coax feedline to a 2-meter, 4-element quad antenna; DX packet clusters; radial wires used with a vertical antenna; and different types of memories used with personal computers. ------------------------------------------------------------------------ RADIO TIPS (RT) These are short items, scattered among the articles in the NEW HAM COMPANION section. _________ Title>RT1:The Joys of FM Simplex Author>Ford, Steve - WB8IMY Source>QST Dec 93, p. 75 Abstract>Long QSOs should be direct between amateurs (Simplex), not through repeaters. They should take care to avoid frequencies where they might interfere with other activities. Digest>In this tip, the writer reminds readers that repeaters can only carry one QSO at a time, so common courtesy requires that QSOs carried by repeaters should be kept as short as possible so that others can get their chance. If two people want to carry on a long QSO on a VHF band, they should try to do it by operating simplex, that is talking to each other directly. They should move to a frequency set aside for simplex operation where they are not likely to be bothered, or bother others. Included in the article is a table of popular FM simplex frequencies on the 6-meter, 2-meter, 1.25-meter, and 70-cm. bands. To find other simplex frequencies, refer to the ARRL Repeater Directory which describes all VHF/UHF band plans in detail. ------------------------------------------------------------------------ GENERAL INTEREST ARTICLES (GI) Title>GI1:Heroics in the Heartland Author>Palm, Rick - K1CE Source>QST Dec 93, pp. 21-26 Abstract>Public service by radio amateurs during the Summer, 1993 floods. Digest>The floods in the upper midwest during the summer of 1993 were the most widespread, long lasting, and devastating floods in the modern history of the United States. But the loss of life was relatively small. Some part of the credit for this must go to the efficiency of communications that were able to get help promptly in the many life-threatening situations that developed. Ham radio volunteers played a large role in this. Mr. Palm has assembled an article made up of reports by ARRL Emergency Coordinators and other members of the ARRL Field Services relating the work done by ham volunteers in various parts of Kansas, Missouri, Iowa, Minnesota, Illinois, and others of the states hardest hit. _________ Title>GI2:A Nation Reborn Author>Enderud, Einar - LA1EE and Wiig, Erling - LA6VM Source>QST Dec 93, pp. 27-31 Abstract>Ham radio activities in Eritrea. Digest>Eritrea, a new nation located near the Horn of Africa and facing the Red Sea, became independent April 27, 1993. Only a little more than a month later, four hams from Norway and one from Japan established the first Eritrean ham station, E35X. The authors were two of the hams who participated and in this article relate their experiences. What had originally started out to be a DXpedition grew to be much more. The five visitors not only established the ham station and put it on the air for many days of intensive operation under the pressure of tremendous pileups, but also they conducted seminars on ham radio at two different places to two different groups. The first was a course of instruction in amateur radio for personnel of the Eritrean Telecommunications Authority (Telecom) and the other was for the students and faculty of the Asmara Technical School. Finally, when the seminars were completed, they helped organize a radio club at the school, donated their equipment to it, and helped install the antennas and start up the station equipment for the club members. During their brief stay, they had made a total of 19,600 contacts and provided a new country for nearly that many hams worldwide. They enjoyed themselves thoroughly and made many friends among the friendly and warm-hearted Eritrean people. _________ Title>GI3:A Cold Season Author>Vaughan, Bruce - NR5Q Source>QST Dec 93, pp. 56-57 Abstract>Fiction. An aged ham keeps in contact with his children by radio. Digest>This is a fictional tale of a ham oldtimer, in his mid-70's, a widower, living alone with his dog. His children live far away and he rarely has the opportunity to enjoy them and his grandchildren. But he keeps in contact with his son who is a ham. At the end of the story, he is pleased to learn from a message received from his son, via packet, that his two grandsons have received novice licenses and will meet their grandfather on 40-meter CW the following Saturday morning. _________ Title>GI4:The First VHF Contest from Cuba Author>Coro, Arne - CO2KK Source>QST Dec 93, p. 58 Abstract>Cuban participation in the June, 1993 VHF QSO Party. Digest>Mr. Coro and a number of other Cuban hams participated in the June, 1993 VHF QSO Party. They were pleased to find sporadic-E openings on 6-meters to the USA on Saturday, and on the following day, similar openings allowed contact with several Caribbean islands. On 2-meters, tropospheric propagation allowed contacts with many U.S. stations in Florida. In the end, they had logged 260 stations on 6-meters in 80 grid squares. On 2-meters they made 62 contacts in 11 grid squares. The author states that news of their success spread through the rest of the Cuban ham community and many Cuban hams are now building single-sideband transverters for 6- and 2-meters, and others are making plans for UHF operations on 432- and 1096-MHz. bands. _________ Title>GI5:Gatti-Hallicrafters: The First Grand Ham DXpedition Author>O'Brien, Mike - N0NLQ Source>QST Dec 93, pp. 59-63 Abstract>A DXpedition sponsored by the Hallicrafters Company in 1947 was an enormous production. Digest>In 1947, Attilio Gatti, an Italian explorer, convinced his friend, Bill Halligan, founder and CEO of the Hallicrafters Company, manufacturer of ham gear, to organize a ham DXpedition to go to the area of East Africa called the "Mountains of the Moon", near Lake Victoria and Mt. Kilimanjaro, in what was then Tanganyika Territory and Kenya, under British control. The expedition was organized in a grand manner. Four special 23-foot long trailers were designed and built, one of which was outfitted as an elaborate and completely equipped ham station. As finally organized and equipped, the expedition moved in a caravan of at least eight vehicles - trucks, station wagons, and tractor-trailers - manufactured by International Harvester. Shipped aboard a freighter, the entourage landed at a port in Kenya in January, 1948. Over the succeeding nine months, it travelled 5000 miles by land logging QSOs all the way. The total number of contacts made is not known, because the logs were somehow lost. The article does not include any estimate of the costs involved in the expedition, but they must have been enormous. If it is true that Mr. Halligan and Hallicrafters absorbed the major part of the cost, it appears that he considered it advertising expense. He must have felt that it was reasonably successful because a few years later Hallicrafters again sponsored a DXpedition, but that time on a much smaller scale, to Clipperton Island. _________ Title>GI6:Ham and Former Ham Share 1993 Nobel Prize Author>Karpf, Stephen - WJ2P Source>QST Dec 93, p. 91 Abstract>The 1993 Nobel Prize for Physics was won by two American hams. Digest>The 1993 Nobel Prize in Physics was awarded to two Americans, Dr. Joseph Taylor, K1JT and Dr. Russell Hulse, ex-WB2LAV. Both developed their interest in radio as hams at young ages. Dr. Taylor was originally licensed at age 13 and Dr. Hulse, also, got his license when he was a teen-ager. Their ham activities led them to become interested in antennas, and from there they graduated to radio astronomy. Working together at the great radio telescope at Arecibo, Puerto Rico, they discovered and studied a binary pulsar. It was this discovery, and their theoretical explanations of what they observed, that earned them the prize. ------------------------------------------------------------------------ 73, Van - W8UOF wvanho@infinet.com