Place your mouse pointer over any of the categories above,
for an active menu of their contents.
Clicking on a major catagory takes you to the
Site Map.
Introduction
This is a map of the part of my web site that has to do with my
Javascript Electronic Notebook. Each page, under each catagory
is a clickable links. Next to each page name is a brief description. All of these web pages
contain Javascript
calculators of one kind or another. In some cases it's as simple as adding a couple of
resistor values together, but in others, rather complicated equations are processed.
Automates the design of a Layer, Air-Core, Inductor. You define
the required inductance, wire type/size, etc., and the program performs the
necessary calculations. Includes optomizing the design for form diameter and turns count.
A transformer, some diodes and a couple of capacitors are all
you need to make a simple Un-Regulated power supply. This supply can then be
filtered using the LM317 Voltage Regulator.
This regulator is intended to follow the Un-Regulated power supply.
This regulator provides the necessary ripple and load regulation required by more
sensitive transistor circuits.
Contains two LC filter calculators. One for a
Butterworth response and one for a
Chebyshev response. Each calculator provides
the ability to enter Cutoff Frequency and Characteristic Impedance. The you
can select Low Pass or High Pass, L-Input or C-Input, and the
number of components (1 to 9).
Contains two calculator for 2-Way and 3-Way speaker cross-over
networks. After you enter the speaker impedances and cross over frequency, you
can select from a variety of speaker responses. At the bottom of the page is
a brief explanation of each type of response.
Contains two calculators for 2nd Order Low-Pass and High-Pass
Active (Op-Amp) Filters. While both calculators perform the same function, one
calculator uses a series of equations and the other uses design tables and
scale factors. Power recomendations are provided at the bottom of the page.
Contains two calculator for 2nd Order Band-Pass filters and
one for 2nd Order Bi-Quad Band-Pass Filters. The 2nd Order Band-Pass Filter
calculators allow for the selection of Gain, Configuration (MFB/VCVS), Center
Frequency, Bandwidth, and initial component specification. One uses equations
to calculate the component values and the other uses design tables and scale
factors. The 2nd Order Bi-Quad Filter provides Low-Pass, High-Pass,
and Band-Pass operation in a single filter. The calculator lets you specify the
center frequency, bandwidth, filter Q, and initial components.
Contains a calculator for a 2nd Order Active Band-Reject Filter.
This type of filter is also known as a notch filter and is useful for eliminating
unwanted QRM and QRN. The calculator allows for the selection of Gain, Configuration
(MFB/VCVS), Center Frequency, Bandwidth, and initial component specification.
The Center-Fed Dipole is
probably the simplest of the single band wire antennas. Easy
to construct and setup. A wire length calculator is included that should
minimize any pruning.
The first section describes the Shorty 40,
40 Meter dipole, originally described by Jact Sobel, W5VM, that fits into the
space of a 20 Meter dipole. The second section is a calculator for designing a
similar short antenna (base loaded) for any other band.
The Electrically Short 2-Band Center-Fed Dipole
is a method for expanding a single band dipole to another lower frequency band, that
still fits in your available space. Contains a calculator to aid in your design.
If you don't have the space for a full size dipole, you might want to
consider a Electrically Shortened Center-Fed Dipole.
The calculator on this page helps you design a single band dipole that uses a
loading coil to shorten the overall length. It may not be as efficient as a
full size dipole, but it should still work fine and give you plenty of contacts.
This provides an possible solution if you want a dipole for multiple
bands, but don't have the room for a full size dipole on all the bands you want. The calculator
on this page helps you work out the details.
You have the space for a full size dipole on 160 or 80 Meters, but
wish it had a little more bandwidth. This page provides the details to expand the
dipoles capabilities.
This page discusses the expansion of a low frequency single band
dipole, for use on other higher frequency bands using traps using coaxial cable.
In many cases the coaxial cable traps help shorten the require space. This page
also provides an alternate configuration that might help increase the efficiency
and bandwidth by using a Fan layout.
Similar in appearance to the Half-Wave dipole, this configuration
can give you wider band coverage and higher feed impedances. You can feed it directly
with open wire line or 50 Ω coax with a 4:1 balun at the feed point.
When you don't have the room for a full size dipole or need to
minimize supports, this may be the antenna for you. This page takes care of
the geometry involved in setting up your antenna.
This page contains several relatively simple calculators that allow you
to work out the design of 2, 3, 4, or 6 element Yagi antennas, for the HF band
(20 to 6 Meters). The bottom of the page describes matching the driven element
using a Gamma Match.
Adding a single driven element to a simple dipole antenna provides
you with 4-5 dB of forward gain and 12 db of F/B Ratio. And, it can be easily tuned on the
ground. The dimensions might be a little much on 40 Meters, but not so bad on
20 Meters and above. Thanks to Bill Orr, W6SAI, for much of this information.
Similar to the page on 2-Element HF Yagis, this page adds a Reflector
element for even more forward gain (7.5 to 8.5 dB) and a better F/B Ratio (20-25 dB).
Again, thanks to Bill Orr, W6SAI, for much of this information.
The matching system that you use depends on many things. This page
describes several types of matching and where they might be applicable.
Delta and T-Match for Balanced feeds and T-Match, Gamma/Omega, and Hair Pin (aka Inducto
or Beta) matching for coaxial cable feeds. There are a couple of drawing that
still need some work.
This sound like this page simply describes a antenna for the
108 to 137 MHz Aircraft band (aka Air Band). But what it really does is describe
the effects of dipole element diameter on the SWR and Gain. There is a nice graph
that show you the SWR and Gain for a variety of element diameters.
This page really discusses the coaxial cables used to feed
VHF/UHF Antennas. Coaxial cables may not have big losses in the HF region, their
losses go up with frequency. This page shows, graphically, why one coax might be
better to use than another. Contains a calculator for determining actual loss
due to cable type, length, and system SWR.
Contains a calculator as an aid for determining antenna element
lengths, based on Frequency, Type (Wire or Tubing), and Diameter (AWG#, inches, mm)
of the element. Also contains a "Table of Horizontal Antenna Lengths from 1 to 7
Half-Wavelengths", a "Table of Vertical Antenna Lengths from 1 to 7 Quarter-Wavelengths",
and "Calculation of K, the Antenna Shortening Factor". All of which is based on
a user's frequency input.
Contains a calculator for scaling an existing antenna design for another
band/frequency. Plus a calculator for adjusting a existing antenna element that is cut for
one frequency to another frequency, in diameter as well as length.
Contains details for each band (160 to 6 Meters) where radio amateurs
have operating privilages. Each band is detailed separately and contains a brief description
of the band and details on it's use. As you move your mouse over each band use detail,
the frequency chart for that band is highlighted.
This is similar to the page on US Amateur Radio Privilages
but only contains priviliges specific to the Technician class operator. This helps
filter out some of the clutter on the other page.
List of Q-Signals commonly used on the ham bands. Q-Signals are short,
three letter, abbreviations to help convey information with the shortest message
possible.
Morse code has been a big part of my 50 years with Amateur
Radio. But I don't have any real issues with the elimination of the Morse
code requirement. This page simply presents my view on learning Morse code
and contains code tests ( 10 each at odd speeds from 5 to 27 WPM) that
can be used on-line or downloaded for local use.
Introduction