EMRFD Index, CD, and Software Errata
Last update this section on (31Oct06)
p500, index. Add both "IL" and "insertion
loss" to the index with "in filters...p3.1, in
receiver roofing filters...p6.50" (10Aug03)
p507, index. The correct name of
VE7QK is Derry (not Jerry) Spittle. (24Feb03)
Book CD: We have found a minor
problem with the CD. When the CD is inserted,
a file "articles.pdf" appears on a directory listing
of the CD drive. Double clicking this file
causes it to run under the Adobe reader. Then,
any of the articles included on the CD can be viewed by clicking
on the listing in the "bookmarks" along the left screen
margin. But the file for W7EL's "Optimized QRP
Transceiver" sometimes produces an error message. It
can be viewed if it is the first file called after the
"articles.pdf" file is run. (20Mar03)
[I have not yet checked this one, and it may be fixed on the
second printing. w7zoi 30Sept03]
Computer Design Programs DTC
and TTC (from CD): Both of these programs include
an estimation of the insertion loss for the bandpass filters
designed by the programs. This is an estimation based
upon the equation given on p 3.10 of the book. If a better
loss number is needed, the filters should be stored with the file|save_as
command, and then analyzed with the general purpose ladder analysis
program, GPLA. GPLA is not an approximation, but
an exact analysis based on the ladder method, presented in detail
in Intro. to RF Design, p51. See also RF Design Magazine,
Sept/Oct., 1983. Although GPLA is exact, it is limited by the element
models used. That is, capacitors have no series inductance and no
loss; inductors have no parasitic capacitance. The analysis is
limited to simple ladders with no mutual elements other than those between
adjacent elements.
Software Manual.
I recently realized that many folks have been trying to fight their way
through the programs, after they realized that they were even there, without
even knowing that a manual existed. The manual is on the book
CD. Insert the CD and look at the CD with Windows Explorer.
Go into the directory Software and then
to the sub directory LADPAC2002.
In this you will fine a long text file, LADPAC2002.txt,
which is the manual. Double click it to open it. You may wish
to copy it to the directory containing the design programs.
(31Oct06)
Articles on the CD:
It is not our intention in general to offer any updates or errata for
any of the magazine articles on the book CD except in some special situations.
A special circumstance that we might consider is if the subject
is of general fundamental interest.
Article #30. Appendix to "A Progressive Communications Receiver,"
QST, November, 1981. This presents equations to calculate the
fixed capacitors needed when a variable capacitor is padded to behave as
if it was a smaller value. A typical application might be the use of
a 365 pF variable to tune over a small frequency range where a variable of
just a few pF is really needed. An error is present in Eq. 3.
of the appendix, p21. The first term on the right hand side of the
equation should have a subscript of U rather than V.
The complete equation set is given here:
Fundament units (Hz, Henry, Farad) are used.
(24Aug06)
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