Hi all,
Well, it is finally out, I see. This is the third printing of EMRFD
that we have been waiting to see. There are minimal revisions. I
don't know what all they did include, for I have not yet seen a new
one. We are at the top of the list, they told us, so soon.
The primary goal for the third printing was to get the errata blended
in and fixed. The folks at the League also found some of their own
that we didn't know about and those will be fixed. They were
primarily grammatical stuff.
As you all know, the CD is useful, but fouled up. Virtually every
one of the early ARRL articles were goofed in one way or another.
The CD is a complete fix.
Finally, there is new software. For the most part, this is just a
bunch of minor changes and clean up things. I made some minor
changes to some of the programs that will, hopefully, make them easier
to use. For example, when you design a filter in XLAD, Low-hi, or
the LC bandpass programs, you can click on one button that stores that
filter circuit in a default file. Then when you open GPLA or
Ladbuild, that circuit is immediately imported. This default file
has become the default starting point for GPLA instead of the default
40 meter bandpass that was there before. (I just catch too much
flack from Roger and from Campbell and others suggesting that my
frequency horizons are limited.)
The programs for LC bandpass filters have changed. I dropped the
tapped input networks, but now design two different filter forms.
One is a simple traditional one with parallel LC resonators and series
capacitors out to the terminations. The other is the modified
topology that is presented in a recent note on my web page (w7zoi.net,
"Design and Experiments" section.). That particular filter topology
is really handy for someone building fairly wide filters (e.g., 10 %),
but still wanting shape symmetry. This is a good one for spectrum
analyzer applications. There are now three LC bandpass programs.
DTC08 and TTC08 are the versions that design double and triple tuned
circuits of two forms. The third is QTC08, which designs a four
resonator filter using the modified topology. Incidentally, this
modified topology has become my filter form of choice and is the one
that I usually pick.
Two versions of Ladbuild are included. The original is there for
folks with a restricted display, while Ladbuild08 is expanded to
handle 45 components, which is handy for those folks designing crystal
ladder filters with a lot of crystals.
A few new programs have been added to the collection:
1) QTC08, described above.
2) Qmeasure08, which features the Q measurement scheme described on
page 7.36. I use that one a lot and wrote a program for it, so tossed
it in for those who might also use the method.
3) Padcap08. This program looks at a single tuned circuit and
answers the question "How do I tune only the bottom 50 kHz of the 40
meter band with a 365 pF capacitor," and variations of that sort.
This calculates the series and parallel capacitors needed to do this,
and includes a graph that lets you see the linearity implications.
4) Spurtune08, which is a Windows version of the program of similar
name that is distributed with IRFD. This has some zoom features and
quick tune things. It tells you where the spurious responses are
going to be if you build a transmitter with a mixer. Rather than the
graphs that we used to see, this generates a display that looks like a
spectrum analyzer screen.
5) ZMAT08. This program designs some (but not all) of the usual
matching networks that we use. These include the L, pi, LCC type T,
LCL type T, and a quarter wave synthetic transmission line with a pi.
An updated manual is in the collection too.
I can hear the wheels grinding, even now. You are all saying "Hey,
this is not right. We don't want to buy a new printing of the book
just to update our programs." The three of us agree, and so did the
folks at the League. So I am going to be posting all of the programs
on my web site so you can download them. This is obviously
restricted to the folks who own a copy of EMRFD, but it goes without
saying that anyone reading this site will already have the book. I'll
get the stuff posted on my web site and then post something here.
Generally I see no reason for folks who already own the book to go get
a new one. We hope that the new printing is cleaner and that the
readers will find it useful. So, enjoy!
73, Wes
w7zoi
|
Wes Hayward wrote: >
>
> Hi all,
>
> Well, it is finally out, I see. This is the third printing of EMRFD
> that we have been waiting to see. There are minimal revisions. I
> don't know what all they did include, for I have not yet seen a new
> one. We are at the top of the list, they told us, so soon.
>
> The primary goal for the third printing was to get the errata blended
> in and fixed. The folks at the League also found some of their own
> that we didn't know about and those will be fixed. They were
> primarily grammatical stuff.
>
> As you all know, the CD is useful, but fouled up. Virtually every
> one of the early ARRL articles were goofed in one way or another.
> The CD is a complete fix.
>
The updated version of Experimental Methods in RF Design is loaded with new,
unpublished projects.
http://www.arrl.org/news/stories/2009/03/16/10704/ hmmm...... fact, fiction, salesmanship? -- GB & 73 KA5OAI Sam Morgan |