Digest of Articles - QST May 94 (Long - 38k)

Digest of Articles - QST May 94 (Long - 38k)

Post by W. E. Van Hor » Wed, 27 Jul 1994 18:34:01

DIGEST OF ARTICLES - QST May, 1994

Following are digests of articles printed in the May, 1994 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:Key Components of Modern Design - Part 1
TA2:You Can Build: A Compact Loop Antenna for 30 through 12 Meters
TA3:A Calibrated Noise Source for Amateur Radio
TA4:Under the Hood V: Solid State Devices

PRODUCT REVIEW (PR)

PR1:Yaesu FT-840 MF/HF Transceiver
PR2:S & S Engineering ARK 40 CW QRP Transceiver Kit

HINTS AND KINKS (HK)

HK1:Beeper Madness
HK2:More "Don't Lose the Little Bits"

TECHNICAL CORRESPONDENCE (TC)

TC1:HF Mobiling: Mag Mounts and Grounding
TC2:Terminated Folded Dipole

NEW HAM COMPANION (NHC)

NHC1:Make Your Mobile More Portable
NHC2:Conquering the Code
NHC3:Interference in Reverse
NHC4:But How Do I Use It?
NHC5:A PC Shopper's Guide
NHC6:The Doctor is IN

RADIO TIPS (RT)

RT1:Traffic Handling is for Everyone
RT2:Join the QRP Craze
RT3:What's DSP

GENERAL INTEREST ARTICLES (GI)

GI1:An Enchanted Sweepstakes Expedition
GI2:Yukon DXing with Flair
GI3:A Look at Digital Audio Broadcasting
GI4:Portable S5
------------------------------------------------------------------------

TECHNICAL ARTICLES (TA)

Title>TA1:Key Components of Modern Receiver Design - Part 1
Author>Rohde, Dr. Ulrich - KA2WEU
Source>QST May 94, pp. 29-32
Abstract>First of a series on receiver design.  Criticises current
design in dynamic range, IMD, i.f. filtering, etc.  Suggests changes.

Digest>This is the first installment of a series of articles discussing
modern communications receiver design and ways that performance may be
further improved in the future.  In this installment, Dr. Rohde
criticizes a number of aspects of current receiver design and suggests
circuit changes that promise to improve performance substantially.

Dynamic range is one of the prime criteria for performance evaluation.
The author points out that there are several kinds of dynamic range that
must be considered.  The first is simple "AGC range"; i.e. the ability
to maintain a constant audio output with varying input signal level.  A
more important criterion can be termed "intermodulation distortion (IMD)
dynamic range".  Second- and third-order IMD increase by 2-dB and 3-dB
respectively as the input signal level increases by 1-dB.  Assuming
linearity at all points on the dynamic scale, at some point each kind of
IMD reaches a level equal to the signal itself; this is the so-called
"intercept point".  This is, by definition, a kind of dynamic range.

The author points out that most receiver testing today measures only
third-order IMD on the assumption that front-end filtering reduces the
second-order distortion to negligible amounts, but he shows that the
diode switching schemes used to select the front end filters as bands
are switched often cause the very kind of IMD that the filters are meant
to eliminate.  Using relays, rather than diodes, to do the switching
would greatly improve results.

Another problem of dynamic range performance measurement is the tone
spacing specified in testing.  Typically, it is 20- or 25-KHz.
separation, but the interference that amateurs must live with often
comes from signals much closer than that!  Filters in the first i.f.
(so-called "roofing" filters) are typically very broad - 15-KHz.
bandwidth is common.  If the IMD test is made with an interfering signal
20-KHz. away, the measurement may show a good result, but if, in real
life, the user is struggling to receive a weak DX signal with strong QRM
5-KHz. away, the result will be very different, indeed.  Clearly, a
first i.f. filter more like the 2- to 4-KHz. SSB filters would be more
appropriate.

Compounding the problem, AGC voltage in most amateur receivers is
derived solely from the second i.f., which usually contains a much
narrower filter.  Often, a strong interfering signal may be outside the
bandwidth of the narrow filter and thus inaudible but well within the
bandwidth of the roofing filter.  In that case, the AGC is of no value,
at all, since the strong signal will tend to block the first i.f.,
greatly reducing the signal-to-noise ratio of the desired signal.  The
author makes a persuasive case that there should be two independent AGC
loops, one around the first i.f. and the second around the second.

Another problem related to the derivation of AGC voltage is the
performance of S-meters in making meaningful measurements of signal
level.  Traditionally, S-9 has been defined as 50-microvolts at an
impedance of 50-ohms.  Scaling that down in 6-dB. steps to S-1 leaves a
signal level of 0.15-microvolts which often is completely readable.  But
if the S-meter scale is to have any realistic meaning, it must have a
number low enough to mean a signal that is barely detectable but not
readable.  Furthermore, in most receivers when a front-end attenuator
is used to reduce overload, the S-meter reading is similarly attenuated.
A completely independent front-end AGC loop that also is the source of
the S-meter readings is, again, the solution.

The last problem that Dr. Rohde addresses in this article is the
desensitization caused by spurious signals and phase noise emanating
from the synthesizer and local oscillator.
                               _________

Title>TA2:You Can Build: A Compact Loop Antenna for 30 Through 12 Meters
Author>Capon, Robert - WA3ULH
Source>QST May 94, pp. 33-36
Abstract>Construction details of a 30-inch (80-cm) diameter transmitting
loop antenna.

Digest>This article gives all construction details for building a
transmitting loop antenna tunable from 10- to 25-MHz.  The author
reports that the total cost of materials was about $35.00.

It is a single-turn loop formed from a length of 5/8-inch (16-mm.)
diameter soft copper tubing 8-feet, 3-inches (2.515-meters) in length
formed into a near-perfect circle slightly over 2-1/2 feet (80-cm.) in
diameter.  The two ends are bent to within 1-inch (25-mm.) of each
other, in line, and are fastened together with a PVC pipe coupling,
which acts as an insulator.

A variable tuning capacitor with a range of 2- to 100-pf. is connected
between the two ends to complete the loop.  Care must be taken to make
the electrical connections with an absolute minimum of electrical
resistance.  This dictates that straps made of strip copper must be
wrapped around the tubing near the ends and soldered over the full area
of contact.  The other ends of those straps lead to the capacitor.

The author used a small capacitor purchased from Ten-Tec, their part
number 23227.  However, its air gap spacing is so small that
transmitting power is limited to 7-watts.  More than that causes the
capacitor to arc over.  For higher power, a capacitor with larger air
gaps must be substituted.

The antenna is mounted in a vertical plane, attached at the top and
bottom of the circle to a mast made of 1-inch (25-mm.) diameter PVC pipe
some 8-feet (2.44-meters) tall.  The ends of the loop and the capacitor
are at the top end of the pipe; the other side of the circle is attached
partway down the mast.  The mast, itself, is supported on a base made of
similar size PVC pipe, cut in pieces and assembled into the shape of a
capital "H" using couplings, elbows, and tees to hold it together.  A
tee at the center of the cross-bar of the "H" acts as a socket into
which the mast is inserted.

At 20-meters, the operating bandwidth is only about 10- to 20-KHz., so
it is necessary to retune the antenna almost every time the frequency is
changed.  The author uses a remote-controlled reversible d.c. motor with
integral 1-rpm gear-reducer to adjust the capacitor.

The antenna is fed by inductive coupling from a small, untuned loop
mounted on the same supporting mast inside the bottom of the main loop.
It is formed from a 20-inch (50.8-cm.) length of RG-8 coax with the
outer covering and braid shield removed.  50-ohm coax feedline is
soldered directly to the two ends of the small loop; in addition, a
small piece of copper braid attaches the braid-side of the feedline to
the main loop at a point directly opposite the variable capacitor.  The
author reports that this feed arrangement provides low SWR feed.  He
does not so state, but presumably he adjusted the size of the small
feed-loop to that which gives the lowest SWR.

Mr. Capon states that the size of this loop can be scaled up to a size
suitable for operating 20- to 40-meters.  This would require a loop
diameter of 1.7-meters (5-feet, 6-15/16 inches), tubing length 5.341
meters (17-feet, 6 inches), and a small loop diameter of 0.34-meters
(1-foot, 1-3/8 inches).
                               _________

Title>TA3:A Calibrated Noise Source for Amateur Radio
Author>Sabin, William E. - W0IYH
Source>QST May 94, pp. 37-40
Abstract>Construction details for a laboratory noise source.
Includes recommended way for getting it calibrated.

Digest>Mr. Sabin, author of this article, previously wrote an article:
"Measuring SSB/CW Receiver Sensitivity", published in QST, October,
1992, pp. 30-34.  In a sidebar to the preceeding article, he gave full
construction information for a True-RMS-to-DC Converter, an instrument
necessary to perform the sensitivity measurements that he described.
The calibrated noise source, which is the subject of the present
article, is an instrument that broadens considerably the range of
receiver performance measurements that can be made.

Uncalibrated noise sources are well known, being used with bridge
circuits in antenna measurements, and for other purposes.  But with the
use of a precisely calibrated source, the noise figure, the excess
noise ratio, and frequency response of receivers can also be accurately
measured.

The article describes construction of two models; one is for use over
the frequency range of 0.5- to 500-MHz., the other covers 1-Mhz. to
2.5-GHz.  Both models use a diode specifically designed and manufactured
for noise generation.  It is manufactured by NOISE/COM, their Model
NC302L.  The circuits of both models are similar and are comprised of a
number of resistors with 1-percent precision, plus a few other common
electronic parts.  The models differ only in that board layout,
components, and coax connectors of the higher-frequency one must be
suitable for microwave use.

The key to success in making accurate measurements is the calibration.
Since not many hams will have access to laboratory instrumentation
capable of calibrating the noise source, NOISE/COM has offered to
calibrate home-built units for $25 plus shipping charges.  The address
is: NOISE/COM Company, East 49, Midland Ave., Paramus, NJ 07652. Contact
Gary Simonyan.  PC boards are available from FAR Circuits, 18N640 Field
Ct., Dundee, IL 60118-9269, for $5.00 each, including domestic USA
shipping.  A board template package can be obtained from the ARRL for an
SASE.  Address the request to Sabin Noise Source Template, Technical
Dept. Secretary, ARRL, 225 Main St., Newington, CT 06111.
                               _________

Title>TA4:Amateur Use of Telescoping Masts
Author>Haviland, R. P. - W4MB
Source>QST May 94, pp. 41-45
Abstract>Describes uses for telescoping masts and safety precautions
required to avoid injury in using them.

Digest>Telescoping masts are commonly used to support TV antennas in
fringe areas.  They are inexpensive, and are available from a number of
suppliers, including Radio Shack.

They are made of relatively light-gauge steel strip, formed into tubing
with a welded seam.  Typically, each piece of tubing is 10-feet
(3-meters) long and the diameter is stepped so that each piece fits
inside the one that precedes it.  When extended, one foot (30-cm.) of
each piece overlaps the next smaller one.  Consequently, a mast made of
five 10-foot lengths (the largest size offered), stands 46-feet in
height.

Telescoping masts are suitable for semi-portable use as well as for
light-duty fixed station uses.  Using them requires secure guying and
careful attention to safety during ***.  The author recommends
that the nested mast be erected on a firm base, guyed at the top of the
first section with four guys and plumbed vertical.  After that has been
accomplished, one or two ladders can be tied to it and the remaining
sections pushed up by one or more people standing on the ladders.  The
mast must be guyed at each joint and at the top.  The article contains
the information necessary to calculate the wind loading, tension on
guys, the maximum size and weight of antennas that can be mounted on
them.  Also the article clearly points out the hazards inherent in
erecting and using such a mast, and strongly advises that safety of
all concerned must be the primary guiding principle in erecting and
using these masts.
                               _________

Title>TA5:Under the Hood V: Solid State Devices
Author>Bergeron, Bryan - NU1N
Source>QST May 94, pp. 46-48
Abstract>Elementary description of diodes, transistors, and ICs.

Digest>This is the fifth installment in a series of articles that
describe the practical aspects of using various types of electronic
components in circuits.   It discusses diodes, transistors, and
integrated circuits (ICs).

Semiconductor diodes are discussed as to their usage, i.e. for signal
switching, power rectification, frequency conversion, and other uses.
They are also classified by their active material: germanium or silicon.
Finally, specialized diodes such as Schottkeys, Zeners, LEDs, and
photodiodes are described.

Transistors are classified as NPN and PNP types, field-effect types
(FETs), JFETs and MOSFETS, and power FETs.  They are also classified by
their packaging and heat-sinking provisions.

Integrated circuits (ICs) are briefly discussed and the difference
between TTL and CMOS designs are mentioned.  Only a hint of the
proliferation of types that are offered can be expressed in an article
so general as this one.

Photographs are included showing a few sample types of the devices
mentioned.
------------------------------------------------------------------------

PRODUCT REVIEW (PR)

Title>PR1:Yaesu FT-840 MF/HF Transceiver
Author>Ford, Steve - WB8IMY
Source>QST May 94, pp. 80-83
Abstract>Performance review of Yaesu's latest "entry level" HF/MF
transceiver.

Digest>The FT-840 is a so-called "entry level" radio, which means that
compromises have been made in the design to hold cost down.  Yet it
contains many, if not most, of the most important features that the
most expensive, state-of-the-art rig contains.

Receiver

The receiver portion has general coverage, 100-KHz. to 30-MHz.  The
large tuning dial has a comfortable feel and can be switched from a
tuning rate of 5-KHz. per knob revolution to 10-KHz.  The LCD frequency
indicator reads the operating frequency to the nearest 10-Hertz.  It has
an RIT control (but not XIT) and two independent VFOs selected by an A/B
switch.  One-hundred tunable memory channels store frequency, mode,
filter, RIT setting, and split-frequency status.  I.F. Shift control is
provided and the switchable AGC provides "Normal" and "Fast" (but no
"Off").  An effective noise blanker is included and a single-step
attenuator provides 10-dB. attenuation.  Squelch is available in all
modes.

Sensitivity and dynamic range are creditable.  With a 500-Hertz i.f.
filter, the noise floor measures -133 to -138 dBm., depending upon
frequency.  A 10-dB. signal plus noise to noise ratio occurs at between
0.6 and 1.0 microvolt, again dependent upon frequency.  The blocking
dynamic range is between 106 and 113 dB. and the third-order IMD dynamic
range is between 88- and 90-dB.  The third-order input intercept varies
from -0.9 to -1.7 dBm.

TRANSMITTER

The reviewer found that he received good reports on the audio when
operating SSB.  He also found that the speech processing is quite
effective.  His one criticism of the phone operation is the lack of a
VOX function.

CW operation is very satisfactory compared with other current
transceivers in the same price class.  First, the CW pitch is easily
changed; more importantly, it is possible to switch the beat oscillator
from one sideband to the other - a delight to CW operators, and a
feature that is missing in many of the most expensive, top-of-the-line
transceivers on the market today.

Operating the digital modes is possible, but not very convenient, for
several reasons.  There is no FSK function, there is no straightforward
way to utilize the narrow-band CW filter in the digital modes, and there
is not even an audio input connector for digital operating.  Audio input
from the TNC must be fed into the mike input jack.  Although it is not
easy, there is a complicated "work-around" scheme to operate RTTY,
PacTOR, etc., which involves operating in split mode, receiving in CW
and transmitting in SSB, then delicately setting the split offset, CW
sideband, and i.f. shift.  The manual recommends RTTY output to be
limited to no more than 50-watts, but the reviewer was able to operate
at full power output for short periods of time with no difficulty.

The reviewer's final conclusion was: "Yaesu's FT-840 offers features and
performance beyond what I would have expected in a "starter" rig just a
few short years ago.  Although it's missing a few things..., it's the
type of radio you will enjoy for years before you feel the need to
upgrade".
                               _________

Title>PR2:S and S Engineering ARK 40 CW QRP Transceiver Kit
Author>Gold, Jeff - AC4HF
Source>QST May 94, pp. 833-85
Abstract>Construction of a QRP transceiver from a kit.

Digest>The ARK 40 is a small package that packs a surprising number of
features that provide good performance and pleasurable operating.  It is
a 40-meter CW transceiver that covers a frequency range of 7.0- to 7.15-
MHz. (20- and 30-meter versions are also available).  It contains a
superheterodyne receiver and a 5-watt transmitter.

The receiver contains a 600-Hertz crystal filter and a 200-Hertz audio
filter, RIT, AGC, and QSK keying.

Receiver performance is quite creditable.  Its noise floor is -127 dBm.,
blocking dynamic range is 95-dB., third-order IMD dynamic range 94-dB.,
and third-order input intercept is 14.2-dBm.

In transmitting, the reviewer found the keying to be excellent.

Mr. Gold found no difficulty in building the kit, although it is not
recommended as a project for beginners.  The manufacturer guarantees
that the completed rig will operate as specified.  The terms of their
guarantee promise that they will fix any problems in the completed unit
if it is returned to them.  If the problem was caused by the
manufacturer, there will be no charge; if by the builder, they will
repair it for a charge not to exceed $25.00.

The manufacturer's list price is $270.  An  optional keyer kit adds
another $40.  The manufacturer's address is: S and S Engineering, 1410
Brown Rd., Smithburg, MD 21783.
------------------------------------------------------------------------

HINTS AND KINKS (HK)
        Conductor: David Newkirk - WJ1Z
                   Sr. Asst. Technical Editor
                               _________

Title>HK1:Beeper Madness
Author>Hoyt, Emerson - WX7E; Moller, Jan - K6FM; and Reinke, John - AB6I
Source>QST May 94, pp. 86-87
Abstract>Construction information for three different beepers to be used
to signal end-of-transmission.

Digest>Many ham repeaters, as well as communicators on commercial and
military circuits, use beepers to signify end-of-transmission. Three
separate circuits to perform the electronic function are described by
the three authors.

The first, described as a "power-miser" beeper, was built by WX7E.  It
utilizes a CD4098BE dual-multi*** IC plus two multiple-logic chips
and a handful of passive components.  All the semiconductors used are
CMOS types and the current consumption is very low.  The unit is powered
by a built-in 9-volt battery without an On-Off switch; the builder
states that it should last for the duration of its shelf-life.

The one by K6FM, in contrast, uses an analog twin-T audio oscillator and
performs the logic with reed relays.  He finds that it works properly
with supply voltages from 6.3- to 9-volts.

The third author, AB6I, described his unit in QST April, 1991, p. 47; in
this issue he is offering an improvement to the circuit.  The
improvement actually eliminates four components from the circuit.
                               _________

Title>HK2:More "Don't Lose the Little Bits"
Author>Roux, Jim - W4YA
Source>QST May 94, p. 87
Abstract>How to use a vacuum cleaner to retrieve small parts out of
a thick carpet.

Digest>To retrieve small electronic parts that may fall on a thick
carpet and disappear, the author holds a single thickness of a nylon
stocking over the end of a vacuum cleaner hose with a *** band.  The
vacuum will lift the part up against the nylon and hold it for
retrieval.
------------------------------------------------------------------------

TECHNICAL CORRESPONDENCE (TC)
        Conductor: Paul Pagel - N1FB
                   Assoc. Technical Editor
                               _________

Title>TC1:HF Mobiling: Mag Mounts and Grounding
Author>Brogdon, Al - K3KMO
Source>QST May 94, p. 88
Abstract>A method of mounting five separate antennas on a van roof.

Digest>Mr. Brogdon, Managing Editor of QST, is also noted for his
exploits in operating CW mobile in both automobiles and motorcycles. In
this letter, he describes a method of mounting five separate whip
antennas on the roof of his Toyota van.

First, he bought four Lakeview Tri-Magnet Mounts and partially
disassembled them.  He ended with four subassemblies, each of which is
comprised of a pair of magnets on a short aluminum bar.  Next he cut a
4-1/2 foot piece of aluminum channel similar to that on which the
magnets are mounted and installed five equally-spaced whip receptacles
along the channel.  Then he attached one of the pairs of magnets
crosswise at each end of the bar, and the other two equally spaced along
the length of the bar so that they would attach themselves to the steel
roof.  The result was a very effective mount for five separate antennas.

He installed an antenna switch on the dashboard and ran separate coax
feedlines through the rear hatch to the individual antennas, so that he
could switch bands from the driver's seat.  To eliminate a severe
ignition noise problem, he ran a length of 1-inch wide copper braid from
the mounting bar to the chassis of the vehicle.  This effectively
eliminated the noise.
                               _________

Title>TC2:Terminated Folded Dipole
Author>Belrose, John S. (Jack) - VE2CV
Source>QST May 94, pp. 88-89
Abstract>A terminated folded dipole transmits usable signals over a very
wide bandwidth, but it under-performs a multiband dipole with tuned
feeders by 3- to 5-dB.

Digest>A terminated folded dipole (TFD) is a non-resonant length of
parallel wires, connected at both ends, fed in the middle of one
conductor.  In the center of the other conductor is a 600-ohm
non-inductive resistor.   They are widely used in military applications
because of their wide-band, non-resonant operation.  Barker and
Williamson (B&W) has supplied the amateur and commercial markets their
Model 370-15 for a number of years.

The author, using Elnec software, made a computer study of a 90-foot
TFD, and also reports the results of a field test of the B&W 370-15.
With the article are two graphic plots that show the results.

The graph showing the results of the computer analysis indicates that
the radiation from the antenna is approximately flat over the range of
6- to 30-MHz. with a slight upward bias.  In dBi, the antenna gain
ranges from about -2 at the low-frequency end to +2 at the high end of
the range.  Below 6-MHz., the gain drops rapidly, falling below -20 dBi
at 2.0 MHz.

The graph of field measurements indicates exactly the same pattern.  In
addition, a dipole mounted at the same height is plotted on the same
graph with the B&W antenna.  Since a dipole should, theoretically, indicate a
gain of slightly more than 2-dBi, as expected the dipole shows a gain of
3- to 5-dBi over the B&W 370-15.

Mr. Belrose concludes that he sees no reason for a radio amateur to use
a TFD, since a dipole, or a  multi-band dipole with tuned feeders,
outperforms the TFD over the entire frequency range.
------------------------------------------------------------------------

NEW HAM COMPANION (NHC)

        The New Ham Companion is a regular section of QST. It features
articles of primary interest to newcomers to the hobby.
                               _________

Title>NHC1:Making Your Mobile More Portable
Author>Mendelsohn, Steve - WA2DHF
Source>QST May 94, pp. 62-63
Abstract>Wire all connections to a mobile rig through one plug so that
it is easy to remove the rig when the car is parked.

Digest>The author makes the point that in many, if not most, urban
areas, it is only prudent to remove mobile transceivers and other
valuable gear from an automobile when it is parked.  He makes it easy to
remove his own transceiver by passing all electrical connections through
one multi-pin connector.  Hence, he needs to remove only one plug when
disconnecting the rig.

The connector that he likes is the Amphenol XLR in-line plug/socket
connector.  It is available with from 3 to 8 pins.

The remainder of the article gives step-by-step instructions of how to
cut each lead and pass it through the XLR plug connector.
                               _________

Title>NHC2:Conquering the Code
Author>Bellamy, Gail - AA8MY
Source>QST May 94, p. 64
Abstract>Mnemonic and other hints for learning Morse code.

Digest>This article contains some hints from the author concerning
methods she used to learn Morse code.  For transcribing, her
stenographic experience taught her that it is easier to write rapidly in
narrow columns on a stenographic notebook.

Her experience in playing music helped in two ways: first, when playing
in an ensemble at a rapid tempo, she knows that if she misses reading
one note, she must skip it and go to the next.  The same is true in
reading letters of Morse code.  Second, the rhythm of Morse code has
similarities to the rhythm of music, and one should think of it
rhythmically.

Finally, she used mnemonics to memorize the individual letters.  For
example, she used the word "around" to represent the letter "A";
"around" is pronounced with an unaccented, followed by an  accented,
syllable - the same as the "dit - dah" of the letter "A".
                               _________

Title>NHC3:Interference in Reverse
Author>Freedom, Tom - W3HVE
Source>QST May 94, p. 65
Abstract>Persuading a neighbor to eliminate a source of noise.

Digest>Mr. Freedom tells the story of radio interference that he
received from a neighbor's house that affected all bands from 160- to
15-meters.  He was unsuccessful in getting the neighbor's cooperation,
so appealed to the FCC, who were less than completely helpful.  Finally,
he got results after appealing to his Congressman.
                               _________

Title>NHC4:But How Do I USE It?
Author>Danzer, Paul M. - N1II
Source>QST May 94, pp. 66-68
Abstract>Elementary instructions in operating a communications receiver.

Digest>This article is comprised of elementary instructions concerning
receiver tuning, the use of narrow and wide bandpass filters, and the
signal width of SSB and CW signals.  The instructions use diagrams
illustrating the spectrum width of the signals plotted on a frequency
scale that represents a radio dial.
                               _________

Title>NHC5:A PC Shopper's Guide
Author>Ford, Steve - WB8IMY and Kleinschmidt, Kirk - NT0Z
Source>QST May 94, pp. 69-71
Abstract>How amateurs use computers.

Digest>The authors list the various major uses that ham radio makes of
computers, and also discusses the various features that current personal
computers should have to be most useful in the hamshack.  The major uses
are: satellite operations, packet radio, contesting, record-keeping,
digital modes of communications, and image transmission.
                               _________

Title>The Doctor is IN
Author>Various
Source>QST May 94, p. 69
Abstract>Questions and Answers of interest to newcomers.

Digest>The questions discussed this month include the effects of rain on
antenna installations; the effect of ice on antennas; the FM "Capture"
effect; the difference between the ARES and the RACES; possible causes
of an indicated drop in the voltage output of a high-voltage power
supply; and the possible need for separate antennas to operate at both
ends of the 6-meter band.
------------------------------------------------------------------------

RADIO TIPS (RT)

These are short items, scattered among the articles in the NEW HAM
COMPANION section.
                               _________

Title>RT1:Traffic Handling Is For Everyone
Author>Kleinschmidt, Kirk - NT0Z
Source>QST May 94, p. 63
Abstract>Explanation of traffic nets.

Digest>In this short item, Mr. Kleinschmidt encourages all hams to
participate in traffic nets.  He lists some typical calls and responses
between the Net Control Station (NCS) and new participants, and makes
other suggestions for a newcomer's first entry into an operating net.
                               _________

Title>RT2:Join the QRP Craze
Author>Kleinschmidt, Kirk - NT0Z
Source>QST May 94, p. 68
Abstract>The fun of QRP operations.

Digest>The author describes QRP operating and lists the activities
specific to low-power operation.  He also suggests that interested hams
might want to join the QRP Amateur Radio Club International (QRP ARCI)
and gives the address: Mike Kilgore - KG5F, 2046 Ash Hill Rd.,
Carrollton, TX 75007.  Please enclose a SASE with two units of postage.
                               _________

Title>RT3:What's DSP?
Author>Ford, Steve - WB8IMY
Source>QST May 94, p. 71
Abstract>Digital signal processing in amateur radio.

Digest>Mr. Ford defines digital signal processing (DSP) and describes
the DSP filters that are currently available for amateur use.  He also
describes the probability that within the forseeable future, DSP
hardware will be developed capable of operating at high r.f.
frequencies.  When that time comes, it will be possible to process
signals in the r.f. stages of receivers and transmitters, and HF
superheterodyne receivers, with their fixed i.f. frequencies, may become
totally obsolete!
------------------------------------------------------------------------

GENERAL INTEREST ARTICLES

Title>GI1:An Enchanted Sweepstakes Expedition
Author>Margelli, Chip - K7JA
Source>QST May 94, pp. 21-23
Abstract>Good contest results using miniature loop antenna.

Digest>Mr. Margelli relates the succes that he had in the 1993 CW
sweepstakes using 150-watts of output, dipoles for 80- and 40-meters,
plus an AEA Isoloop miniature loop antenna for bands 10-, 15-, and
20-meters.  His QTH was the mountaintop home of Pedro Piza, Jr. - NP4A.

He had an excellent score in the contest, and logged a total of 1388
QSOs.   Of that total, almost half were on 40-meters; but when the
higher bands were open, he worked 10-, 15-, and 20-meters using the tiny
loop antenna, with excellent results.
                               _________

Title>GI2:Yukon DXing With Flair
Author>Reisenauer, John - NL7TB
Source>QST May 94, pp. 24-26
Abstract>Operating Sweepstakes from the far north.

Digest>Mr. Reisenauer and his friend, Kent - NL7VJ, operated in the
1993 phone Sweepstakes from a campsite on the Alcan Highway in Yukon
Territory in late November while temperatures routinely plunged below
-40 degrees F. each night.  Their "shack" was an RV and they mounted a
Triband beam, plus other antennas, on a tower on the roof of the
vehicle.

Their operation was very successful and they logged a total of 930
contest QSOs plus some 600 non-contest contacts, including many DX
contacts.
                               _________

Title>GI3:A Look at Digital Audio Broadcasting
Author>Kleinschmidt, Kirk - NT0Z
Source>QST May 94, pp. 27-28
Abstract>Digital audio in future radio broadcasting.

Digest>Digital audio is defined as a modulation scheme in which an audio
signal is sampled and digitized, the digital signal is processed and,
perhaps, compressed, and one or more such signals are impressed on a
carrier for broadcasting.  In some of the proposed broadcasting modes,
as many as 20 stereo pairs would be broadcast in a single channel using
a spread spectrum technique.  In all cases, the fidelity would be such
as can now be achieved only on compact disks (CDs).

Under consideration are plans to broadcast on "S-band" (2310-2360 MHz)
either directly from satellites to consumers, or by impressing the
digitial signals on a sub-carrier alongside conventional FM signals.
However, it is unlikely that commercial broadcasting will begin before
1997, at the earliest.
                               _________

Title>GI4:Portable S5
Author>Gartenberg, Sharon Machlis - KC1YR
Source>QST May 94, pp. 50-53
Abstract>American hams visit Slovenia.

Digest>Mrs. Gartenberg, along with her husband, Lee - KA1USL, spent
their 1993 summer vacation operating ham radio in Slovenia.  They stayed
in the Alpine resort town of Cerkno (population 2200) as guests of the
Cerkno Radio Club, who allowed free use of the club station on a
mountain top, surrounded by stunning scenery in all directions.  
Slovenia's prefix, S5, was still so new that, when KC1YR/S5 came on the
air, a pileup was immediate and never let up.  For that reason, she
never left the 20-meter band and logged more than 900 QSOs in 3 days!
------------------------------------------------------------------------