QEX_2011_05_06.pdf
(
6345 KB
)
Pobierz
$
5
NothingButPerformance
TheTS-590S
KenwoodhasessentiallyredefinedHFperformancewiththeTS-590ScompactHFtransceiver.TheTS-590SRX
sectionsportsIMD(intermodulationdistortion)characteristicsthatareonparwiththosetopoftheline
transceivers,nottomentionhavingthebestdynamicrangeinitsclasswhenhandlingunwanted,adjacent
off-frequencysignals.*
•
HF-50MHz100W
•
AdvancedDSPfromtheIFstageforward
•
DigitalIFFilters
•
HeavydutyTXsection
•
Built-inAntennaTuner
•
500Hzand2.7KHzroofingfiltersincluded
•
2ColorLCD
KENWOOD U.S.A. CORPORATION
Communications Sector Headquarters
3970 Johns Creek Court, Suite 100, Suwanee, GA 30024
Customer Support/Distribution
P.O. Box 22745, 2201 East Dominguez St., Long Beach, CA 90801-5745
Customer Support: (310) 639-4200 Fax: (310) 537-8235
ADS#13211
*For1.8/3.5/7/14/21MHzAmateurbands,whenreceivinginCW/FSK/SSBmodes,downconversionisautomaticallyselectedifthefinalpassbandis2.7KHzorless.
May/June 2011
About the Cover
John Stephensen, KD6OZH, built two ver-
sions of a clean stable VFO circuit that uses an
Analog Devices ADF4157 fractional N PLL IC
and an Atmel ATtiny2313 microcontroller. One
version is a 390 to 425 MHz VHF/UHF VFO, and
the other is a 75 to 150 MHz oscillator he built
for a 3 to 16 MHz HF transceiver.
QEX (ISSN: 0886-8093) is published bimonthly
in January, March, May, July, September, and
November by the American Radio Relay League,
225 Main Street, Newington, CT 06111-1494.
Periodicals postage paid at Hartford, CT and at
additional mailing ofices.
POSTMASTER: Send address changes to:
QEX, 225 Main St, Newington, CT 06111-1494
Issue No 266
Harold Kramer, WJ1B
Publisher
Larry Wolfgang, WR1B
Editor
Lori Weinberg, KB1EIB
Assistant Editor
Zack Lau, W1VT
Ray Mack, W5IFS
Contributing Editors
Production Department
Steve Ford, WB8IMY
Publications Manager
Michelle Bloom, WB1ENT
Production Supervisor
Sue Fagan, KB1OKW
Graphic Design Supervisor
David Pingree, N1NAS
Senior Technical Illustrator
Advertising Information Contact:
Janet L. Rocco, W1JLR
Business Services
860-594-0203 – Direct
800-243-7768 – ARRL
860-594-4285 – Fax
Circulation Department
Cathy Stepina,
QEX Circulation
Ofices
225 Main St, Newington, CT 06111-1494 USA
Telephone: 860-594-0200
Fax: 860-594-0259 (24 hour direct line)
e-mail:
qex@arrl.org
Subscription rate for 6 issues:
In the US: ARRL Member $24,
nonmember $36;
US by First Class Mail:
ARRL member $37, nonmember $49;
International and Canada by Airmail: ARRL member
$31, nonmember $43;
Members are asked to include their membership
control number or a label from their QST when
applying.
In This Issue
Features
3
A Stable Low-Noise VFO for VHF-UHF Transceivers and
Transverters
John B. Stephensen, KD6OZH
15
A Flexible 2-Port Network Calculator Tool
By Tom McDermott, N5EG
25
Next Issue in
QEX
26
A Study of Tall Verticals
By Al Christman, K3LC
32
Optimum Height for an Elevated HF Antenna
By Kazimierz “Kai” Siwiak, KE4PT
39
A New Theory For the Self Resonance, Inductance and Loss
of Single Layer Coils
By Alan Payne, G3RBJ
45
Letters
In order to ensure prompt delivery, we ask that
you periodically check the address information on
your mailing label. If you ind any inaccura-
cies, please contact the Circulation Department
immediately. Thank you for your assistance.
46
Upcoming Conferences
Copyright © 2011 by the American
Radio Relay League Inc. For permission
to quote or reprint material from
QEX
or any ARRL publication, send a written
request including the issue date (or
book title), article, page numbers and a
description of where you intend to use
the reprinted material. Send the request
to the ofice of the Publications Manager
(
permission@arrl.org
).
Index of Advertisers
American Radio Relay League: .........Cover III,
Cover IV
Array Solutions ............................................ 48
ATRIA Technologies, Inc: ............................. 47
Down East Microwave Inc:........................... 47
Kenwood Communications: .................Cover II
National RF, Inc: .......................................... 38
Nemal Electronics International, Inc: ........... 38
RF Parts ................................................ 45, 47
Tucson Amateur Packet Radio: ................... 48
QEX – May/June 2011
1
The American Radio
Relay League
Larry Wolfgang, WR1B
Empirical Outlook
The American Radio Relay League,
Inc, is a noncommercial association
of radio amateurs, organized for the
promotion of interest in Amateur Radio
communication and experimentation,
for the establishment of networks to
provide communications in the event of
disasters or other emergencies, for the advancement
of the radio art and of the public welfare, for the
representation of the radio amateur in legislative
matters, and for the maintenance of fraternalism and
a high standard of conduct.
Old
QEX
Article Files
Have you ever carefully examined a spider web? Perhaps you have come across an elabo-
rate web suspended between trees across a trail through the woods, as I have. Or perhaps you
have watched a spider spinning its web among plants in a garden. The patterns can be truly
amazing and beautiful, especially if you happen to spot the web early in the morning, with drop-
lets of dew clinging to the threads and the early light hitting it in just that perfect way.
Sometimes there will be several threads stretched for 6 or 10 feet across a space, with the
thread making an almost perfectly horizontal line. I always wonder how the spider managed to
cross that space, and how it could stretch the thread so tight. From a few supporting threads,
the spider is able to then weave an intricate pattern, often with concentric circles and carefully
drawn radial lines all designed to catch its next meal of some unsuspecting insect that may ly
into the trap and be caught.
After all that work, some careless animal (you or me?) may walk along that trail and not notice
the web until it is a tangled mess of silk that we usually can’t wait to rip off our face or clothes,
all the while imagining the monster spider in attack mode, ready to bite whatever just destroyed
all that hard work. Or maybe it was a sudden heavy rain that washed away the web. Spider webs
are rather tenuous creations, in any case. They are built as a labor of love and as a matter of
survival, perhaps in a few hours or a day, and can be gone in an instant. They may be rebuilt in
the same location, or perhaps the spider will move on to a less vulnerable spot.
For many years I have known that the
QEX
iles section of the ARRL website is very popular.
Readers enjoy being able to download iles related to the articles they have read in the pages
of
QEX
. Those iles include computer program iles, source code for microprocessor projects,
EZNEC
antenna model iles, Microsoft
Excel
spreadsheets and more.
Many authors maintain their own websites, where they post various articles and iles related
to those articles. There they can update a program ile when some new feature is added
or when a bug is discovered and ixed. They can post pictures of new versions of the
project, and even of new projects. Some authors maintain websites that become reader
favorites. Have you looked at
w7zoi.net
lately? Wes Hayward, W7ZOI, is an ever popular
author (
Experimental Methods of Radio Frequency Design
along with many
QST
and
QEX
articles) with lots of interesting information on his website. How about Jack Smith, K8ZOA, with
www.cliftonlaboratories.com
? These are just two of many examples of websites that many
QEX
readers probably have bookmarked for regular visits.
Much like those spider webs, the World Wide Web can be a rather transient place. Sometimes
new domain names are obtained and old names are allowed to fade away. Sometimes a sud-
den “storm” may cause a once popular site to lie dormant, no longer updated or just no longer
available. Whatever the reason, individual websites can be the most subject to sudden closure,
with the loss of the iles and information formerly available there. That is one of the reasons we
have encouraged authors to share their iles with us to be posted to the
QEX
iles section of the
ARRL website. ARRL is in it for the long haul, and although authors may have updated iles or
ixed software bugs on their websites, we have a way for readers to obtain the information (at
least as it may have existed when the article was published) for many years to come. After all,
we know that someone may pick up an old issue of
QEX
and discover an article that interests
them now, years after that issue was published.
During recent months I have had a signiicant number of requests for old iles that were men-
tioned in
QEX
articles and posted to our QEXiles website. This reminds me that even a website
intended to be “secure” and available for the long haul can be lost as quickly as those delicate
spider webs. You see, when the ARRL unveiled a new website as part of a completely new
design, for some reason older iles were not transferred to the new structure. I had been assured
they would be, because we knew how popular that section of our website was, but suddenly the
iles were gone. Some authors indicated that readers had contacted them, and the author was
able to supply the requested ile, but that was not always the case.
Over the past few weeks I found (or perhaps re-discovered) what I had forgotten. At least
some of the old iles had been archived for ARRL HQ Staff access. I have begun what may be
a rather long process of recreating the tables of ile names and descriptions, author names and
links to those old iles. As I write this, I have added the 2006 iles to our new website at
www.
arrl.org/qexiles
. In the coming weeks and months, I plan to continue restoring older iles, as
time permits. It won’t happen immediately, but I will recreate as much of that broken web as I
can.
If you are looking for an older ile, please check the ARRL website to see if it has been
restored. If you try to download a ile and ind that it is not the ile you expected, or if you ind
other problems, please let me know. Since I don’t see an automated way to do this, I will be
copying iles and text, and creating hyperlinks as those iles are put into the new web structure.
Our new web may not be exactly like the old one, but hopefully it will fulill all our needs.
ARRL is an incorporated association without
capital stock chartered under the laws of the state
of Connecticut, and is an exempt organization
under Section 501(c)(3) of the Internal Revenue
Code of 1986. Its affairs are governed by a Board
of Directors, whose voting members are elected
every three years by the general membership. The
oficers are elected or appointed by the Directors.
The League is noncommercial, and no one who
could gain inancially from the shaping of its
affairs is eligible for membership on its Board.
“Of, by, and for the radio amateur,” ARRL
numbers within its ranks the vast majority of active
amateurs in the nation and has a proud history of
achievement as the standard-bearer in amateur
affairs.
A
bona ide
interest in Amateur Radio is the only
essential qualiication of membership; an Amateur
Radio license is not a prerequisite, although full
voting membership is granted only to licensed
amateurs in the US.
Membership inquiries and general corres-
pondence should be addressed to the
administrative headquarters:
ARRL
225 Main Street
Newington, CT 06111 USA
Telephone: 860-594-0200
FAX: 860-594-0259 (24-hour direct line)
Oficers
President:
KAY C. CRAIGIE, N3KN
570 Brush Mountain Rd, Blacksburg, VA 24060
Chief Executive Oficer:
DAVID SUMNER, K1ZZ
The purpose of
QEX
is to:
1) provide a medium for the exchange of ideas and
information among Amateur Radio experimenters,
2) document advanced technical work in the Amateur
Radio ield, and
3) support efforts to advance the state of the
Amateur Radio art.
All correspondence concerning
QEX
should be
addressed to the American Radio Relay League,
225 Main Street, Newington, CT 06111 USA.
Envelopes containing manuscripts and letters for
publication in
QEX
should be marked Editor
, QEX
.
Both theoretical and practical technical articles are
welcomed. Manuscripts should be submitted in word-
processor format, if possible. We can redraw any
igures as long as their content is clear.
Photos should be glossy, color or black-and-white
prints of at least the size they are to appear in
QEX
or high-resolution digital images (300 dots per
inch or higher at the printed size). Further
information for authors can be found on the Web at
www.arrl.org/qex/
or by e-mail to
qex@arrl.org
.
Any opinions expressed in
QEX
are those of
the authors, not necessarily those of the Editor or the
League. While we strive to ensure all material
is technically correct, authors are expected to
defend their own assertions. Products mentioned
are included for your information only; no
endorsement is implied. Readers are cautioned to
verify the availability of products before sending
money to vendors.
2
QEX – May/June 2011
John B. Stephensen, KD6OZH
3064 E. Brown Ave, Fresno, CA 93703; kd6ozh@arrl.net
A Stable Low-Noise VFO for
VHF-UHF Transceivers
and Transverters
Most new VFO designs seem to use direct digital synthesis, but DDS
designs suffer from increased spurs as the output extends into the VHF and UHF
range. This modern PLL design eliminates that problem.
When I first became interested in
Amateur Radio, variable frequency oscil-
lators (VFOs) used large air-core coils and
mechanically variable capacitors with 100:1
gear-reduction drives. These were easy to
design and build but not very stable beyond
10 MHz. For SSB operation on the upper
HF bands and all VHF and UHF bands,
crystal-controlled converters were neces-
sary. Later on, frequency synthesizers using
multiple phase-locked loops (PLLs) allowed
the construction of stable electrically tuned
VFOs for SSB radios operating on HF, VHF
or UHF bands. These were complicated
devices, however. A 2 meter radio that I built
in 1993 used a 3 × 12 × 17 inch chassis to
contain such a synthesizer. By 1999, I could
combine a direct digital synthesizer (DDS)
chip and a PLL chip, and achieve a simi-
lar result for an HF radio.
1
The DDS spurs
increase as the PLL output increases into the
VHF and UHF range, though.
There is now a much simpler option — the
sigma-delta fractional-N PLL. The principles
of its operation have been described previ-
ously in
QEX
.
2
In that case, a CPLD-based
integer-N PLL and a microcontroller were
combined to make a low frequency frac-
tional-N PLL. A complete fractional-N PLL
is now available in a 16-pin TSSOP package
and operates at up to 6 GHz! The lead spacing
is 0.65 mm (25.6 mils) so it can be soldered
by hand. When combined with commercial
off-the-shelf voltage controlled oscillators
(VCOs), simple and stable synthesized VHF
and UHF VFOs can be created.
Figure 1 — Top and bottom views of the 390 to 425 MHz VFO (1.5 × 3 inch circuit board).
1
Notes appear on page 13.
QEX – May/June 2011
3
Plik z chomika:
ei6kd
Inne pliki z tego folderu:
QEX_2011_09_10.pdf
(7578 KB)
QEX_2011_07_08.pdf
(8752 KB)
QEX_2011_03_04.pdf
(6671 KB)
QEX_2011_01_02.pdf
(5538 KB)
QEX_2011_05_06.pdf
(6345 KB)
Inne foldery tego chomika:
Antennenbuch Rothamel
Baluny i Ununy (Baluns and Ununs)
Bem D.J Anteny i rozchodzenie się fal radiowych
Fider Byron Goodman
Niektóre zagadnienia dotyczące pracy BALUNÓW
Zgłoś jeśli
naruszono regulamin