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Monthly newsletters are available to
members through one of three options:
(A) Receive the newsletter via NOFARSnet,
a distribution system sponsored by Yahoo Groups. To subscribe to NOFARSnet,
access
http://www.yahoogroups.com . In the search box, enter NOFARSnet and then follow the instructions to subscribe. There is no cost
but distribution is limited to NOFARS members so include your call sign or
name to allow authentication as a current member.
Or you may
subscribe to NOFARSnet by sending an e-mail request to
n4uf@nofars.net
(B) The www.nofars.net web site will
announce when each monthly e-mail newsletter is available. Members may
request the current issue by sending an e-mail to
n4uf@nofars.net
after the
web site announcement is posted. No permanent list will be kept so it will
be up to each member to make a request each month.
(C) For those without Internet access, a printout of each monthly e-mail newsletter
is available by postal mail to members who send a supply of self-addressed,
stamped envelopes to the editor in
advance. Be sure to use “forever” stamps on your envelopes. Send your
envelope supply to Billy Williams, N4UF; 10028 Garden Lake Court;
Jacksonville, Florida 32219-4380 or bring to a NOFARS meeting. 12 stamped envelopes will
be needed for each year. If a member without Internet access prefers to
receive the Balanced Modulator without providing envelopes, an annual
surcharge of $6 may be paid. This does not include NOFARS
dues.
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YOUR INVITATION TO
JOIN NOFARS
At only $5 a year, NOFARS membership is a bargain that is hard to
beat. NOFARS membership offers many advantages and shows that you
support organized ham activities in this area. Whether you are a
newcomer or a longtime operator, you are invited to join our group.
To join or renew your NOFARS
membership, send your dues to Billy Williams, N4UF; 10028 Garden Lake
Court; Jacksonville, Florida 32219-4380. Please make checks payable to NOFARS.
You may join for multiple years at this low rate.
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NORTHERN FLORIDA
TRAFFIC WEB PAGE
NOFARS member Earl Leach, WX4J has
established a web page which lists items of interest to traffic
(message) handlers. It can be accessed via
http://home.comcast.net/~wx4j
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146.73 MHz STARKE REPEATER
The 146.73 MHz. Repeater in Starke has good coverage for those
traveling U.S. 301 and other roads in Bradford County. It is located on
the WEAG radio tower on SR100 and is operated by NOFARS VP Ben
Dickerson, K4EL. The Bradford ARES net meets each Thursday at 7PM on the
repeater.
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LEARNING MORE ABOUT ELECTRONICS
A NOFARS meeting program covered tips on
learning more about the electronics theory on which Amateur Radio exams are
based. Reference books are valuable in this regard. Reference and textbooks
can be purchased cheaply at used book stores and online. The information in
entry-level and even mid-level texts has not changed much over the years so
an older edition is sufficient. The sequence of topics is fairly standard in
most basic textbooks regardless of the author. Some widely used textbooks
used in electronics courses include:
Electronic Communications
by Robert Shrader.
Basic Electronics
by Alexander Grob
Electricity And Electronics
by Allen Mottershead
Electronic Fundamentals: Circuits,
Devices and Applications by
Thomas Floyd
Digital Fundamentals
by Thomas Floyd
Data And Computer Communications
by William Stallings
The ARRL Handbook
(formerly Radio Amateur’s Handbook) is
also a good book to study.
Books and study guides also are
available for download via Internet. The progression of study is shown below
along with some of the main subject areas in each category.
Direct Current (DC) Theory: Atomic
structure, electronic units and prefixes, scientific and engineering
notation, conductors and insulators, Ohms Law, multimeters, series and
parallel circuits, DC voltage sources, voltage and current dividers.
Alternating Current (AC) Theory: Magnetism,
generators, oscilloscope, inductance, transformers, capacitors, reactance,
impedance, time constant, resonance, complex numbers and notation.
Electronic Devices: Diodes, bipolar
transistors, field effect transistors, thyristors.
Analog Circuits: Rectification, regulation,
amplifier, power control.
Digital Circuits: Numbering systems
(binary, hexidecimal), logic gates, combinational logic, sequential logic,
D/A and A/D conversion, multiplexers.
Microprocessors: Internal structure, basic
operation, busses, machine language, higher level languages, computer
architectures.
Basic Communications Systems: System
layout, RF transmission, receivers, modulation, measurements, transmission
lines, antennas, television, repeaters, trunking systems, communications law
and procedures, specialty modes.
Digital Communications Systems: Coding,
Decoding, Networks, RF, telephone systems, VoIP.
After acquiring an understanding in
these areas, one may progress further into the specialties of the
electronics field. Some of the more popular specialties include Computer
Electronic Technology, Advanced Communications Technology, Industrial
Electronics and Robotics. For basic electronics, a math background which
includes algebra and trigonometry is needed. High school texts and
electronic math books can be helpful. An understanding of calculus and other
higher level math is needed for advanced circuit design.
Hardware lab trainers and project kits
can help you understand the theory better through laying out circuits and
testing devices. You should become proficient in using the multimeter,
oscilloscope, logic analyzer and other basic test gear. Computer software
programs such as Electronic Workbench allow you to design and
troubleshoot circuits on your computer screen.
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BUYING A HOME WITHOUT ANTENNA RESTRICTIONS
No countywide zoning restrictions
against outside Amateur Radio antennas are contained in Jacksonville’s
ordinance code. While some city zoning employees mistakenly apply a 35-foot
height limit on structures to include ham installations, Amateur Radio antennas are exempted from classification as “structures.”
When dealing with city government, it is
best to research in advance. The ordinance code can be accessed online
through www.coj.net or through a search using "Jacksonville Florida
ordinance code."
If you don’t live in Duval County,
many other jurisdictions have their ordinance codes available via Internet.
You can order a copy of the code for most jurisdictions or conduct a search
using the name of your jurisdiction followed by words such as “ordinance
code.” Local libraries also usually have copies.
Notwithstanding our favorable treatment
by city government in Jacksonville and Florida statutes which provide that
government agencies must reasonably accommodate ham antennas with minimum
necessary regulation, anyone desiring to erect an outdoor antenna can face
many hurdles.
Terms such as “reasonably accommodate”
and “minimum necessary regulation” are open to interpretation with many
local governments in Florida justifying height limits as low as 15 feet as
being reasonable. There has been mixed success in court, but claiming ones
rights to an outdoor antenna can be very expensive.
Most subdivisions, especially Planned
Unit Developments (PUDs) built in the past ten years, have restrictions
against outside tower and antenna installations. These restrictions, known as CCRs, are
recognized as contracts between private individuals and are stricter than zoning laws.
When you move in, you accept.
If you are looking for a new home or lot upon which to build, chances are
that if you purchase in any area built in the past decade, you will
encounter difficulty in putting up most any type of outside ham antenna. If
there are no overhead power lines or no outside antennas, other than small
TV dishes, on other homes in a
subdivision, you can be sure there are restrictions in place.
One good idea is to deal with a real estate agent and tell him or her that
you want a home with no antenna restrictions. Usually, there is no charge for a
home buyer to consult with an agent to help find a property.
A strategy is to find a home that is adjacent, but not inside a subdivision. If you buy a home on the edge of a restricted subdivision,
you may also be able to purchase unrestricted
adjacent property just outside the development. Your editor uses this
approach.
Properties along major thoroughfares with acreage that are not part of a
subdivision are probably your best bet. You might even consider buying a
large lot and having a home built.
Not all restrictions may be disclosed
especially during early stages of a transaction. When you negotiate, have
your agent put wording into offer sheets that state the sale will be void if
antenna restrictions are uncovered.
Restrictions are posted on the Duval
County Clerk of Court web site. Do a search in the "official records"
section using the name of your subdivision or the name of the Home Owners
Assn. Most other jurisdictions also post deed restrictions.
Otherwise, you can visit the Clerk of Court office and request an official
copy.
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HAM RADIO MYTHOLOGY
By The OH OH
I say this because, you continually see the same ones
cropping up over and over again.
What follows is just the tip of the iceberg, and I've
chosen them only for their frequency (it’s pun time) of appearance. While
based in fact, a lot of neophytes and old timers alike will affront them,
but that just means they're biased; a fact that will become evident soon
enough.
Probably the single, most prevalent Myth within these
pages deals with the much-aligned G5RV, doublet antenna. As designed by Jim
Varney (SK aka Dead Short to Ground), the antenna was intended to operate on
20 meters, yet be usable on 40 and 80, preferably with an antenna tuner, yet
have a reasonable radiation pattern and SWR. It fulfills its mission quite
well. The myth parts are; there wasn't a shortened (junior) version, and it
was not designed as an all-band antenna. Yes, of course, you can
stick a big antenna tuner in front of it, and load it up on most (not all)
of the HF bands, but the efficiency suffers, and the radiation pattern
stinks. Adding some confusion was the fact, that early versions (there were
several) had a BALUN. Apparently, after thinking about it, he (G5RV) wrote
other articles wherein he admonished its use.
Speaking of the lowly BALUN... It should always be
printed in caps as it is an acronym for BALanced/UNbalanced. It is, in the
strictest of terms, a transmission line transformer. Without getting into a
whole bunch of discussion, there are two basic types; a voltage BALUN, and a
current BALUN. Typically (not always) these are listed as 4:1 and 1:1. In
the former case, it could also be a 1:4. Remember, it is a transformer, and
its primary and secondary windings may be reversed. Quite obviously, there
is a lot more to BALUNs than this over-simplified description. The myth part
is, few folks know which one to use in any given situation. This may take me
out on a limb with the purists, but if the input to the BALUN is from an
antenna tuner (built in as part of it or not), the correct choice is a 1:1
current BALUN.
Another BALUN Myth deals with whether one should be
used, or not. If it was strictly necessary, our forefathers would have never
gotten on the air! In some cases, a choke BALUN made from coiled-up coaxial
cable will suffice, but even that isn't necessary if the feed line is
perpendicular to the plane of the antenna. Yes, there will be some
imbalance, and the pattern could be a bit skewed. However, assuming a BALUN
will suddenly correct a poor radiation pattern, a lousy SWR, or a specific
RFI issue, is a Myth!
Antennas, no matter what they are made of, or what
frequency they operate on, follow a given set of known parameters. There is
nothing mythical about them. The laws governing their operation have long
since be laid down by the likes of Kirchhoff, Maxwell, and many others. What
is mythical is the hype which runs rampant through the amateur radio
marketing community. This includes exaggerated gain figures, superfluous
efficiency ratings, obscene power handling capabilities, and super-low
radiation angles. It's bad enough that antenna manufacturers resort to such
ham-fisted (I just couldn't help myself with this pun) behavior, far too
many of us believe it! If you doubt this, then why is it that too-many
amateurs believe that a low SWR, or the number of DX contacts you can make
on any given antenna are marks of merit? Talk about mythology!
Believing that a low SWR is a guarantee of a great
transmitted signal is a Myth. A Dummy load is 1:1, but does not radiate
much. You can get two pieces of metal, find the 50 Ohm impedance between
them for the feed line point and call it a Dipole. But many times, the low
SWR does not mean it will transmit across an open field.
And then there the are Myth-a-Logical Inventors who
have sold the Magic Box under many names with the claim to be the perfect
antenna without such cumbersome things like wires and radiating elements!
Great for basements and apartments!
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