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DIGEST OF ARTICLES -- QST, October, 1993
Following are digests of articles printed in the October, 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:The SunSwitch (70)
TA2:Inside the Grounded-Grid Linear Amplifier (105)
TA3:TAPR's Digital Deviation Meter (132)
TA4:Schematics at Your Fingertips (195)
TA5:The Earth Detunes My Antenna (224)
PRODUCT REVIEW (PR)
PR1:AEA PK-900 Multimode Communications Processor (287)
PR2:Ramsey Electronics FX-146 2-Meter Transceiver Kit (341)
HINTS AND KINKS (HK)
HK1:More on Coax-Cable Connector Installation (383)
HK2:Curing VU-Meter Pinning in the MFJ-624D Hybrid Phone Patch (430)
HK3:The Multi-Tuner (451)
TECHNICAL CORRESPONDENCE (TC)
TC1:Sense the Right Way to Go With the HANDI-Finder (476)
LAB NOTES (LN)
LN1:Printed-Circuit Board Circus (509)
NEW HAM COMPANION (NHC)
NHC1:Mountain-Top VHF Operating: A New Adventure! (542)
NHC2:Nobody Talks to Me! (572)
NHC3:Stalking the Fox (594)
NHC4:The First Contest (609)
NHC5:LOWfing on 1750 Meters (621)
NHC6:The Doctor is IN (640)
RADIO TIPS (RT)
RT1:The Right Polarization for the Job (661)
RT2:Using an Autopatch to Report an Accident (669)
RT3:SWR (687)
GENERAL INTEREST ARTICLES (GI)
GI1:VP2MFA "Do-able" DXpedition (696)
GI2:Yagi: The Man and His Antenna (730)
GI3:The Radio Clubs of Romania (777)
GI4:How to Be a DXer (802)
GI5:Hams Test Antennas Aboard Space Shuttle COLUMBIA (815)
------------------------------------------------------------------------
TECHNICAL ARTICLES (TA)
Title>TA1:The SunSwitch
Author>Bryce, Michael - WB8VGE
Source>QST Oct 93, pp. 24-27
Abstract>Construction article for a controller to regulate the charge
current from a bank of solar cells into a battery.
Digest>Mr. Bryce presents a design and construction article for building
a charge controller to control the current flow from a bank of solar
cells into a battery. It is a smaller and less expensive version of the
"FET Charge Controller" that he described in QST, January, 1992.
In operation, the unit measures the state of charge in the battery (by
measuring the voltage across its terminals). It turns the current "on"
if the charge is low, and keeps it that way until the battery is fully
charged. If the solar array is not putting out a high enough voltage,
the controller switches it off.
There are three LED indicators on the front panel which show if the
battery is charged, charging, or off-line. The unit is designed to
handle charging current up to 6 amps, which is enough to handle two
48-watt photovoltaic panels. The current is switched on and off by two
power MOSFETs, each rated at 3 amps. If the intended load will not
exceed the 3 amp level, one of these can be omitted. Alternatively, the
current capacity can be increased up to a total of 14 amps by modifying
the circuit board as the author describes in detail in the article.
A complete wiring diagram and parts list is included. A kit of parts,
including everything except the enclosure, is available from SunLight
Energy Systems, 2225 Mayflower NW, Massilon, OH 44646 for $42.50,
including domestic shipping. A p.c. board and parts overlay template
are available, for an SASE, from the ARRL Technical Department
Secretary, 225 Main Street, Newington, CT 0611.
_________
Title>TA2:Inside the Grounded-Grid Linear Amplifier
Author>Bruene, Warren - W5OLY
Source>QST Oct 93, pp. 28-30
Abstract>The most popular kind of linear amplifier for use on HF bands is
the grounded-grid type. This article gives a thorough analysis of
vacuum tube operation in this type of circuit.
Digest>The operation of a triode in grounded-grid service can be
described by a set of "Anode Current Characteristic Curves". These
curves are determined by laboratory measurements of the voltages on the
plate and filament, and anode current, under d.c. conditions. They are
published by the tube manufacturers.
The article includes a graph of this type for an idealized triode
roughly similar to the Eimac 3-500Z. The author shows how this graph
can be used to calculate essentially all of the operating
characteristics of the amplifier.
His final summary states: "The operating conditions of a grounded-grid
linear amplifier are determined by the anode load resistance and
drive-voltage amplitude. The anode load resistance determines the slope
of the load line. There is practically no relationship between the
correct tube load resistance and the effective internal resistance...of
the amplifier."
_________
Title>TA3:TAPR's Digital Deviation Meter
Author>Johnson, Lyle - WA7GXD
Source>QST Oct 93, pp. 31-38
Abstract>An article describing the characteristics of FM signals,
including the number and amplitude of sidebands, plus a description of
the digital deviation meter developed by the Tucson Amateur Packet Radio
club (TAPR).
Digest>Any FM signal, including FSK, contains a carrier and multiple
sidebands. If the audio modulation is a single tone, as is the case in
a 2200 Hz. AFSK signal, the r.f. will be made up of a carrier plus
sidebands, both above and below the carrier frequency, at intervals of
2200 Hz. The total number of sidebands, and their amplitudes, are
determined by the amplitude of the modulation.
At the other end of the link, the received signal is filtered by the
i.f. bandwidth. If the number of sidebands (the "deviation of the
signal") make the signal too wide, the higher-numbered sidebands are cut
off. This results in distortion of the received signal. Alternatively,
if the deviation is too low, the detected audio may be too weak to
override the noise level. Hence, controlling the deviation of an FM
transmitter is important, but most hams do not have the equipment
necessary to measure it.
Tucson Amateur Packet Radio (TAPR), a non-profit corporation, has
developed an inexpensive deviation meter and is making it available in
kit form to the ham community. This article is a thorough description
of the design and construction of the kit.
The article explains the principle of operation by pointing out that any
FM receiver's detector output is a direct measure of deviation. In
principle, all one needs to do to measure the deviation is to measure
the output voltage. But the rub comes in calibrating the detected
voltage in terms of frequency deviation; the calibration may drift over
time. TAPR's design solves the problem by building a self-calibrator
into the system.
The unit contains an analog FM signal-processing system, an
analog-to-digital converter, and a microprocessor. Five times per
second, the analog circuit samples the highest and lowest detector
voltages, they are digitized, and the difference between them is
compared with a table of values stored in the microprocessor's memory.
It translates the measured voltage difference into a deviation reading
in KHz., accurate to 0.1 KHz.
How does the microprocessor get its table of values? It obtains it
automatically, by itself! Every time the power switch is turned on, a
calibration oscillator running near the i.f. frequency comes on. It
starts at 10 KHz. below the i.f. center frequency and steps at intervals
of 1 KHz. to 10 KHz. above the center frequency. At each step, the
analog detector voltage is sampled, digitized, and its value held in
memory. This assures accuracy of measurement over a reasonable
operating time.
The article contains complete wiring diagrams, parts lists, construction
hints, and a description of how to hook it into any FM transmitter. A
complete kit of parts including a construction and operating manual and
software, but not including a case, is available from TAPR, P.O. Box
12925, Tucson, AZ 85732-2925 for under $100. Printed circuit board
template is not available from the ARRL.
_________
Title>TA4:Schematics at Your Fingertips
Author>Schofield, Ken - W1RIL
Source>QST Oct 93, pp. 39-40
Abstract>Using WINDOWS PAINTBRUSH to draw electronic schematics on
DOS-based computers.
Digest>Many hams now have, or are buying, IBM-compatible computers that
use an operating environment called WINDOWS. It comes equipped with a
sub-program called PAINTBRUSH. Using PAINTBRUSH, one can draw lines,
circles, or any other shape, in full color, on the computer screen.
Mr. Schofield, using WINDOWS PAINTBRUSH, prepared a complete set of
electronic circuit symbols, and has them stored in his computer. Using
the symbols plus the line-drawing ability of PAINTBRUSH, he can draw
electronic circuit diagrams of almost any complexity on his screen. Once
it is on the screen, with a dot-matrix- or laser-printer, he can print
it on paper. In the article, he explains how he made the symbols and
how he uses them to draw diagrams.
The author has made his file of predrawn symbols available for the
asking. Anyone with a computer plus modem can call the ARRL telephone
Bulletin Board System (BBS) at (203) 666-0578 and download the file into
their own computer. Alternatively, send a blank floppy disk (either a
5-1/4" 1.2 MB. disk, or a 3-1/2" disk of either 720 KB. or 1.44 MB.
size) in a suitable disk mailer, and enclose return postage, and the
file will be mailed.
_________
Title>TA5:The Earth Detunes My Antenna
Author>Hall, Jerry - K1TD
Source>QST Oct 93, pp. 41-44
Abstract>Report of a study of the effects of various types of ground on
the resonant frequency of dipoles.
Digest>Most hams realize that the earth has a major influence on the
radiation pattern of an antenna, but we tend to forget that its presence
also affects the resonant frequency, as well. Mr. Hall has studied the
effects of the ground on a half-wave dipole antenna using NEC2, a
method-of-moments computer program. This article contains some of his
findings.
Antenna reference books, such as the ARRL Antenna Book, tell us that the
end effects in a wire dipole cause a "half-wave" antenna to be
physically about 5 percent shorter than a free-space half-wavelength.
Thus the common formula usually given for calculating the length of wire
is to divide 468 by the frequency in MHz. to get the answer in feet.
The author finds that, when modeling a 3.75 MHz. dipole in free space
with a length calculated by the formula, the impedance at the center
would be 67.5-j41.8 ohms. But this is not resonant since, by
definition, at resonance the impedance will be a pure resistance. For
resonance, the antenna must be lengthened by about 2.5 percent so the
formula becomes 479.6 divided by the frequency in MHz. The center
resistance of the antenna at resonance is 72.2 ohms.
The author now brings the earth back into the calculation and models the
dipole at 50-feet (15-meters) height over "perfect ground", meaning the
approximate equivalent of seawater or an infinite copper plate. The
antenna must be shortened so that the proper factor is 469.5 divided by
frequency. Shortening the antenna lowers the radiation resistance,
which is now 59.6 ohms.
"Real ground", meaning dry land, varies substantially in its
characteristics as measured by dielectric constant and conductivity.
What is defined, for radio purposes, as "very good land" is the rich
soil typical of the area from Dallas, TX to Lincoln, NE; very poor to
extremely poor is in the middle of cities, with heavy industrial areas
or high buildings.
Analysis of the antenna at 50-feet (15-meters) over soil at the two
extremes indicates that for very good ground the factor in the formula
should be 470.8, and for poor earth it should be 473.9. For the
80-meter antenna with a total length of about 125 feet (38 meters), the
range of differences is only about 10-inches (25 cm.), but that
represents the same difference in length as would be caused by a change
of frequency of about 25 KHz.
The author goes on to explore the effects at different heights and also
studies the effect of ground conditions on the radiation patterns in the
elevation plane. In his summary, he acknowledges that his work has
simply verified what all hams have known from the beginning, that is
that the only way to obtain a resonant antenna is to prune it on-site.
But his work does give the reader a better idea of what specific effects
are at work.
-----------------------------------------------------------------------
PRODUCT REVIEW (PR)
conductor: James W. Healy, NJ2L
Sr. Asst. Technical Editor
_________
Title>PR1:AEA PK-900 Multimode Communications Processor
Author>Ford, Steve - WB8IMY
Source>QST Oct 93, pp. 71-73
Abstract>Specifications and operational review of AEA's PK-900
Communications Processor. Performance on VHF Packet is little changed
from that of earlier models; but on HF modes, performance is distinctly
better.
Digest>AEA, the manufacturer of the Model PK-232, one of the most
widely-used multimode communications processors (MCPs), has recently
begun to broaden its line with more sophisticated (and expensive)
models. Their "high-end" models DSP-2232 and DSP-1232 feature digital
signal-processing and a number of other advanced features. The model
PK-900 is intermediate with performance features broader than the
PK-232, but not up to the high-end models. Its most substantial
addition over the PK-232 is the availability of two independent radio
ports. One is designed specifically for packet operation while the
other supports all the HF digital modes as well as 1200-bit/s VHF
packet.
Another major difference is that the PK-900 does not use LED indicators
on the front panel. Instead, it has a large, amber liquid-crystal
display that reports operating conditions in plain-English words. The
lower part of the rectangular display is a 20-bar tuning indicator which
can be changed by software commands to several different modes of
display. As an optional feature, a 9600-bit/s modem can be added. This
allows communications with certain satellites that operate at that data
rate.
The author used the PK-900 in all of its different modes and reports
that in VHF packet, it is comparable to that of all other modern MCPs
that he has used. But on HF digital modes, including packet, AMTOR,
PACTOR, RTTY, and CW, its performance is distinctly superior to older
models. He gives a number of illustrations of this that he determined
by rapidly changing from the PK-900 to his other (unidentified) MCP when
operating on HF digital modes under difficult operating conditions of
QRM, weak signals, and QRN. In each case, he found the information
throughput using the PK-900 to be distinctly faster than with the older
model. He attributes some of this improved performance to the 8-pole
Chebyshev band-pass filter in the PK-900.
Like the other AEA MCPs, the PK-900 includes the Signal Identification
and Acquisition mode (SIAM). Operating in that mode, the unit will
automatically identify a signal, if it corresponds to any of the types
that have been included in the unit's software. When it does, it will
switch its mode to correspond to that of the received signal.
The author reports in his final summary that, for the advanced
digital-mode enthusiast, the PK-900's extensive standard-feature set and
optional support of 9600-bit/s operation raise its value, but it is
overkill for more pedestrian applications.
_________
Title>PR2:Ramsey Electronics FX-146 2-Meter Transceiver Kit
Author>Bloom, Jon - KE3Z
Source>QST Oct 93, pp. 73-74
Abstract>Description of the Ramsey FX-146 2-Meter Transceiver built from
a kit. Its performance is sufficient to let the builder "get on the
air", but not up to the standards of commercially-built equipment.
Digest>Among the electronic kits that Ramsey offers are test equipment
and general hobby-electronic items, plus several amateur products. One
is the FX-146 2-meter FM transceiver. It covers 140-180 MHz. in 12
discrete channels, selected by a 12-position switch. The local
oscillator is synthesized and the 12 channels are selected and
hard-wired during assembly.
The front panel has only two knobs, Volume and Squelch, the 12-position
switch, an LED indicator that signals when the unit is transmitting, and
two jacks for microphone and speaker. The jacks are spaced so that they
will accept an ICOM-compatible speaker/microphone accessory plug.
The reviewer built a unit following directions in the manual. They
instruct the builder to proceed one sub-section at a time and not to
continue until each is operating properly. His opinion is that the
manual and instructions are "pretty good" but inexperienced builders may
want some help from more experienced hams.
The completed transceiver performs with acceptable sensitivity but with
limited dynamic range. Its front-end filtering has a broad band-width
which allows it to be used for receiving information and commercial
frequencies but leaves it open to interference caused by intermodulation
distortion and also by images.
The reviewer's final summary was: "Inexpensive and relatively easy to
build, the FX-146 will get you on the air, but with less than
factory-built performance."
------------------------------------------------------------------------
HINTS AND KINKS (HK)
conductor: David Newkirk, WJ1Z
Sr. Asst. Technical Editor
_________
Title>HK1:More on Coax-Cable Connector Installation
Author>Collins, Lewis D. - W1GXT
Source>QST Oct 93, p. 75
Abstract>One ham's opinion of the best way to attach PL-259 plugs onto
coax cable.
Digest>The writer offers some hints about the best and most reliable
way of soldering PL-259 plugs on the ends of coax cable. His approach
is similar to the instructions that are printed in common amateur
literature with two exceptions:
First, he strongly advises the use of a 100-watt soldering iron such as
the American Beauty Model 3138. The editor interjects a note that such
irons are routinely used by stained-glass artists. Anyone who has
difficulty finding one for sale in electrical/electronic outlets should
check the Yellow Pages under "Craft Supplies" and "Glass-Stained and
Leaded".
Second, he suggests the plastic outer sheath as well the dielectric be
cut with a dull knife so that it will be less likely to nick the braid
or conductor underneath it.
He advises the following steps:
1. Remove 3/4" of outer sheath without nicking the braid.
2. Using the soldering iron, quickly tin the braid for at least
3/8" starting at the end of the outer sheath.
3. File the solder on the braid to a uniform thickness.
4. Using the dull knife, (better yet, a tubing cutter), cut
through the tinned braid and part way through the dielectric,
5/16" from the end of the jacket. Be careful not to nick the
center conductor.
5. Grasp the small piece of dielectric that is not completely
cut off and twist it with pliers back and forth to break it
loose along the cut.
6. Put the connector on the end, solder to the braid through the
four holes around the connector, and solder the center
conductor in the center pin. Snip off any excess length of
center conductor that protrudes through the pin.
_________
Title>HK2:Curing VU-Meter Pinning in the MFJ-624D Hybrid Phone Patch
Author>Stauffer, Bill - W5ICV
Source>QST Oct 93, pp. 75-76
Abstract>Overcoming a deficiency in the MFJ-624D phone patch that caused
the meter to indicate full-scale whenever the phone line was connected.
Digest:The writer describes a problem with his MFJ-624D phone patch.
When he installed it according to instructions in the MFJ manual, the
patch operated properly except that its VU-meter pegged when the phone
line was connected. He investigated and discovered what the problem
was. He fixed it by installing a 600-ohm isolation transformer obtained
from Mouser Electronics.
With the letter, he includes a wiring diagram and a dimensioned drawing
of a small piece of perf-board, indicating where the invidual components
should be mounted for installation inside the cabinet of the MFJ unit.
He invites anyone with further questions to contact him at Rio Rancho,
NM, (505) 891-8746.
_________
Title>HK3:The Multi-Tuner
Author>Wilson, Curtis - W0KKQ
Source>QST Oct 93, p. 76
Abstract>Combining three antenna tuners into one assembly, used with
three antennas.
Digest:The writer uses several antennas for receiving and transmitting
on a single band, and finds it helpful to be able to switch rapidly from
one to another. A simple selector switch is not enough because each of
his antennas must be tuned, using an antenna tuner. His solution is to
have three antenna tuners, one for each antenna so that each is always
tuned and can be instantly switched.
He strapped MFJ Model 948 Deluxe Versa Tuner II antenna tuners together
with aluminum straps, and interconnected them with short coax jumpers.
He shows a block diagram indicating the electrical interconnections amd
a pictorial diagram showing the three tuners mounted one atop the next.
----------------------------------------------------------------
TECHNICAL CORRESPONDENCE (TC)
conductor: Paul Pagel, N1FB
Associate Technical Editor
_________
Title>TC1:Sense the Right Way to Go With the HANDI-Finder
Author>Moell, Joe - K0OV
Source>QST Oct 93, pp. 77-78
Abstract>Adding a delay line to the HANDI-Finder to convert the "figure
8" to a cardioid (i.e. heart-shaped) pattern.
Digest:The writer offers a modification to the "HANDI-Finder" described
by B. Leskovec: "Build the HANDI-Finder!" in QST, May, 1993, pp. 35-38.
The writer has found the HANDI-Finder to be an admirable unit for
"Fox-Hunting" except for the fact that its null is bi-directional. Mr.
Moell offers a simple modification that converts the original "Figure 8"
to a "cardioid" pattern with a single null.
The modification requires inserting a carefully trimmed piece of
miniature coax as a delay line in the lead to one of the two antennas.
His letter gives detailed instruction as to how the delay line should be
dimensioned and trimmed, where in the circuit it is to be inserted, and
how it is to be physically mounted on the circuit board of the HANDI-
Finder. He also shows photographs of both sides of the circuit board
with the jumper installed.
He reports that the operation is very effective in giving an unambiguous
reading of direction in "Fox-Hunting". Its only drawback is that the
unit is no longer usable over many bands; the delay line must be cut for
an individual band and will only perform on that band.
------------------------------------------------------------------------
LAB NOTES (LN)
conductor: Steve Ford, WB8IMY
Asst. Technical Editor
_________
Title>LN1:Printed-Circuit Board Circus
Author>Ford, Steve - WB8IMY
Source>QST Oct 93, pp. 79-80
Abstract>Preparing PC-boards at home.
Digest>Mr. Ford presents a simulated question-and-answer series that
explains how printed circuits can be obtained for people interested in
building electronic projects. He mentions that many projects written up
in hobby electronics and amateur radio publications contain printed
circuit patterns and, often, indicate sources where etched and drilled
boards can be obtained. He then goes on to explain how people who are
unable or unwilling to buy etched boards can design an etch their own.
He explains how to prepare boards for etching by applying wiring
patterns through direct drawing by special resist-pens, by pressure-
sensitive tape, or by dry transfer of patterns. He also explains the
photo process by which printed circuit patterns can be applied via a
photo-sensitive coating and photographic printing techniques onto the
copper. Finally, he explains the etching process using a corrosive
chemical, usually ferric chloride.
Finally, he gives the names and addresses of several sources where
appropriate supplies can be obtained, including Radio Shack as well as
more specialized suppliers.
------------------------------------------------------------------------
NEW HAM COMPANION (NHC)
This Section is a standard monthly feature of QST. It contains
articles of primary interest to newcomers to amateur radio.
_________
Title>NHC1:Mountain-Top VHF Operating: A New Adventure!
Author>Putman, Pete - KT2B
Source>QST Oct 93, pp. 60-62
Abstract>Operating in the VHF QSO Party from a peak in the Kittatiny
Mountains using gear for 3 bands back-packed to the top.
Digest:The author relates his experiences during the June, 1993 VHF QSO
Party when he carried three transceivers and three antennas to the top
of a peak in the Kittatiny Mountains of northwestern New Jersey at an
elevation of 1500-feet above sea level. He had to carry the equipment
on his back for about 2-miles up a part of the Appalachian Trail from a
parking area. The site is the base of a state fire tower and it gave
him access to the densely populated East Coast concentration of UHF/VHF
activity.
His transceivers covered 6-meters, 2-meters, and 70-centimeters, each
running 3-watts output. He also carried an electronic keyer which he
had modified by mounting two push-button switches in the top cover. He
uses them in lieu of a paddle while sending CW. His antennas were a
5-element Yagi on 6-meters and two 9-element Yagis on the other two
bands.
He operated for 4-hours and made 85 contacts in more than 36
grid-squares. Of the total, 26 contacts were made on 6-meters in 12
grid-squares; on 2-meters there were 39 contacts in 13 squares; and on
70-centimeters, 20 contacts in 11 squares. Almost all contacts were
using SSB and CW.
_________
Title>NHC2:Nobody Talks to Me!
Author>Ford, Steve - WB8IMY
Source>QST Oct 93, p. 63
Abstract>How a beginner can "break the ice" and have QSOs on VHF/UHF
bands.
Digest>Mr. Ford addresses the problem facing newcomers to the VHF/UHF
bands who find it difficult to open a QSO with another ham. On
repeaters, it is not the custom to call "CQ". Instead, custom dictates
that one announces their presence by giving their call sign followed
with the word "Listening!" Often, other hams who are monitoring the
repeater do not take that as a request for a QSO, hence do not reply.
The author gives a number of suggestions of how to open conversations,
meet people, and form a circle of friends. He points out that many hams
who spend time on VHF are basically shy and feel slightly uncomfortable
talking with strangers. But they usually will welcome requests for
information and advice from newcomers, so that offers the possibility of
opening initial contacts.
_________
Title>NHC3:Stalking the Fox
Author>Kearman, Jim - KR1S
Source>QST Oct 93, pp. 64-65
Abstract>Describing amateur "Fox Hunts", i.e. using radio direction-
finding gear to locate hidden transmitters as a competitive activity.
Digest>Mr. Kearman describes the sport of "Fox Hunting" or "T-Hunting".
It is the game of hide-and-seek conducted on radio! A hidden
transmitter, usually on the 2-meter band, is hidden somewhere and hams
with various kinds of direction-finding equipment try to find it. The
article discusses kinds of equipment suitable for use and ways of
organizing hunts.
_________
Title>NHC4:The First Contest
Author>Cotterman, Charlie - KA8OQF
Source>QST Oct 93, p. 66
Abstract>Getting started in ham radio contests.
Digest:The author tells his personal experiences during his first ham
radio contest. He made many mistakes and got only a very low score, but
he realized that: "Everyone's got to start somewhere." He did, and
presumably is, by now, an experienced contester.
_________
Title>NHC5:LOWfing on 1750 Meters
Author>Ford, Steve - WB8IMY
Source>QST Oct 93, pp. 67-68
Abstract>Operating in the 160-190 KHz. band.
Digest>There is a radio band at frequencies between 160 and 190 KHz.
that is open to everyone with no license required. It is not a very
popular band because there are severe restrictions on the kind of
equipment that may be used. First, the power input to the final
amplifier must not exceed 1-watt. Second, the antenna, including
transmission line, must not exceed 15 meters in length (about 50 feet).
Nevertheless, there are some amateurs who are experimenting and making
contacts over respectable distances.
More information can be obtained from: The Longwave Club of America, 45
Wildflower Rd., Levittown, PA 19057
_________
Title>NHC6:The Doctor is IN
Author>Various
Source>QST Oct 93, pp. 69-70
Abstract>A regular monthly feature in this section, it is devoted to
questions and answers of interest to newcomers.
Digest>This month the questions discussed had to do with: electronic
keyers; calling CQ on the 80- or 160-meter bands; a problem with the
volume control on an HT transceiver; the legality of using two-letter
abbreviations of call-signs during DX-net operations; accidental
activation of the autopatch on a repeater; RFI on a transceiver caused
by a computer; and plugging accessory boards into expansion slots in
computers.
------------------------------------------------------------------------
RADIO TIPS (RT)
These are short items, scattered among the articles in the NEW HAM
COMPANION section.
_________
Title>RT1:The Right Polarization for the Job
Author>Ford, Steve - WB8IMY
Source>QST Oct 93, p. 62
Abstract>In VHF and UHF operation, antenna polarization is usually
horizontal in SSB and CW work, vertical in FM.
_________
Title>RT2:Using an Autopatch to Report an Accident
Author>Regent, Richard - K9GDF
Source>QST Oct 93, p. 65
Abstract>Instructions for reporting accidents via mobile radio by using
the telephone 911 through an autopatch.
Digest>If one comes upon an accident, report it via radio in this
manner. Get on the air, give yor call sign, and announce "Emergency
patch". That gives you priority.
Dial the access code, followed by "911". Tell the dispatcher who
answers that you are a radio amateur reporting an accident; then give
the exact location, extent of injuries, if any, whether there is a fire,
or a spill of fuel or liquids, and whether traffic is blocked. Then
sign off but continue to monitor the frequency.
_________
Title>RT3:SWR
Author>Schetgen, Robert - KU7G
Source>QST Oct 93, p. 70
Abstract>A primer on SWR: what it is, its effects, and how it can be
monitored and/or reduced.
------------------------------------------------------------------------
GENERAL INTEREST ARTICLES (GI)
Title>GI1:VP2MFA "Do-able" DXpedition
Author>Stephens, Stu - K8SJ/VP2MFA
Source>QST Oct 93, pp. 21-23
Abstract>Recounting a "DXpedition" in the luxurious surroundings of a
resort hotel on the Caribbean island of Montserrat.
Digest>Mr. Stephens describes a holiday that he and his family took to
the Caribbean island of Montserrat. He selected that island after
reading the Sierra Club Guide to the Caribbean. From the ARRL he
received the Reciprocal Licensing/VP2M Packet and learned that visiting
hams are welcomed to the island. He had no difficulty obtaining a
license to operate as VP2MFA.
He carried with him on the trip his HF transceiver, which has a built-in
power supply and keyer, and his antenna tuner. In addition, he took a
30-foot mast that he made from a collapsible TV-antenna tripod and
sections of TV-mast tubing and smaller diameter conduit which would
telescope with the mast tubing. He also carried antenna wire, twin-
lead, and coax to cover whatever contingencies might arise in getting an
antenna up in the air. The antenna parts fit into a ski-bag, which he
characterized as "a familiar sight to Customs and Air Line clerks...."
When he arrived, he found that the apartment that they had rented opened
onto a court where he erected his mast and put up a 100-foot long
inverted vee that he could use on all bands.
He enjoyed acting as a highly desirable DX station that created "instant
pileups" when he came on the air. Operating 3- or 4-hours per day,
during the two weeks' vacation he logged 3,073 QSOs. His biggest
surprise was 80-meter European DX that came on after midnight, local
time. He reported that they provided "the few truly monster pileups".
_________
Title>GI2:Yagi: The Man and His Antenna
Author>Welsh, Robert H.
Source>QST Oct 93, pp. 45-47
Abstract>The story of the invention and development of the "Yagi" (more
properly the "Yagi-Uda", or perhaps just the "Uda") antenna.
Digest>All hams today know what a Yagi antenna is, but many may not
know how it got its name. Mr. Welsh tells the story of Hidetsugu Yagi
and Shintaro Uda, the two Japanese engineering professors who were
responsible for the development of the antenna.
In the west, and especially in the United States, we are very careful to
credit a discovery or invention to the person who actually conceived the
idea and/or did the work. In some other countries, notably in Japan,
the teacher or mentor of a researcher is often given the major credit
for what his pupil discovers. Professor Yagi was a senior professor at
Tohoku University in Japan, and Assistant Professor Uda was a younger
man working under Yagi's supervision.
Uda conceived the idea of placing parasitic elements near a dipole
radiator and discovered that making them slightly longer caused them to
act as reflectors; slightly shorter, as directors. Working in the
University laboratory, he made careful measurements with numbers of
elements. From that, he obtained the complete engineering data
regarding the design of antennas with one reflector and any number of
directors, exactly as they are built today. Professor Yagi, in his
subsequent publications and speeches always credited his young assistant
with having made the actual discovery.
The first published article describing Uda's work appeared under his own
name in the Proceedings of the Imperial Academy of Japan in February,
1926. The first publication in the United States was written by Uda in
the Proceedings of the IRE in March, 1927. But Yagi applied for the
Japanese patent December 28, 1925, and for a U.S. patent in September,
1926. Yagi's American patent was issued in May, 1932 as U.S. Patent
Number 1,860,213. Now it is Yagi's name that is most commonly used to
identify the antenna.
The author points out the surprising fact that hams paid little
attention to the antenna until near the end of the 1930's. By then, the
popularity of the W8JK wire beam had wakened the interest of hams to
beam antennas, in general. But it was the advent of television
immediately before, and especially after, World War 2 that made Yagi-Uda
antennas the most popular of all antenna types.
_________
Title>GI3:The Radio Clubs of Romania
Author>Pataki, George - WB2AQC, ex-YO2BO
Source>QST Oct 93, pp. 48-50
Abstract>Amateur radio in Romania has emerged from the former tight
government control and is burgeoning. The radio clubs that formerly
were used by the government to exert control now are free and are
encouraging more young people to join in the fun.
Digest>The author, who was born in Romania, visited his native country
in 1993 and reports the current status of ham-radio there. Prior to the
1989 overthrow of the former Communist dictatorship, all amateur radio
activities were closely controlled by the government. But they did
actively encourage and sponsor a great number of radio clubs, completely
paid for by the government. Now, most of these clubs still exist and
are owned by county governments, manufacturing companies, schools, and
other organizations. There are not many amateur stations in private
homes.
The author feels that ham radio, like the whole country, is going
through a period of transition. A great many enthusiastic hams are
there, and purely private ham activities will inevitably grow as the
economic condition of the country develops.
_________
Title>GI4:How to Be a DXer
Author>Mastroianni, Joe - AA6YD
Source>QST Oct 93, pp. 51-52
Abstract>Humorous recounting of a bad case of DXing "disease".
Digest>This is a tongue-in-cheek article that explains that DXing is a
disease that is nearly incurable. He relates how he allowed himself to
be drawn into pileups, what an effect it has had on his family life, and
how he has been driven to seek counsel from a "shrink".
_________
Title>GI4:Hams Test Antennas Aboard Space Shuttle COLUMBIA
Author>Siwiak, Kai - KE4PT
Source>QST Oct 93, pp. 53-55
Abstract>Amateur radio aboard the space shuttle COLUMBIA.
Digest>In April, 1993, the space shuttle COLUMBIA went into space on
mission STS-55. It carried two complete amateur radio stations, one in
the orbiter itself and the other in the German Space Lab, which was
carried in the shuttle's cargo bay. The one in the shuttle was called
SAREX (for Shuttle Amateur Radio EXperiment) and the one in the Lab
SAFEX.
Before the mission, arrangements were made by the ARRL, NASA, the
Motorola Amateur Radio Club in Plantation, Florida, the IBM Radio Club
in Boca Raton, Florida, and a number of indidual hams, to perform a
controlled experiment. The goal was to make accurate measurements of
the signal levels on the 2-meter band received from both transmitters
through the duration of two passes over Florida.
The SAREX antenna was mounted on the window of the shuttle, whereas the
German Space Lab carried an external antenna. The author does not
describe either antenna, but the reader must assume that the antenna
attached to the window was some kind of a dipole and the SAFEX external
antenna some kind of a beam.
In contrast to the lack of any specifications for the antennas in orbit,
the antennas on the ground are described in great detail. The IBM and
Motorola clubs built elaborate receiving antennas and signal-reception
data were carefully recorded with both vertical and horizontal
polarization.
Signal levels have been calculated from the accumulated data and the
article includes plots showing received signal strength of both
polarities second-by-second for the entire duration of two successive
orbital passes. From the data, the directive gain of both transmitting
antennas were calculated and also plotted.
The indicated gain of both antennas changed substantially over the
duration of the pass due to changes in ground reflectivity from
different elevation angles of the shuttle seen from the ground. The
calculation shows that the SAFEX antenna outperformed the SAREX antenna
by about 11 dB. The peak absolute gain shown by the SAFEX antenna is
about 6 dBi. and that of the SAREX approximately minus 7 dBi., both
within an estimated accuracy of plus or minus 5 dB.
----------------------------------END-----------------------------------
73, Van - W8UOF
wvanho@infinet.com