[Antennas] Announcing SmartSmith version 1.5.3

[Robert Lay]

Please visit http://www.qsl.net/w9dmk to download the latest version of
SmartSmith, the free Smith Chart program.

This release incorporates the following major changes:

Main Window -
The main window has been shrunk to fit comfortably in an 800 x 600 display
environment. The earlier releases were all designed for a 1024 x 768 (XGA)
display environment, and users with older systems had great difficulty in
using the system on an 800 x 600 (SVGA) display. In order to accomplish the
re-sizing of the main window, the Smith Chart display was reduced in size to
85% of its former size. The 9 different matching section controls were also
removed from the main window and given their own modal dialogue boxes that
are exclusively selected and shown floating above the main window only when
in use.

Range of Control over Elements -
All matching section controls other than those involving lengths of
transmission line were extensively revised to provide the user with a
greater range of values. In this release, each control has a range of 5
decades and 50 discrete values within each decade. For example, the Series
Resistance matching section now starts at the value 0.1 ohm and extends to a
maximum value of 10000 ohms in 250 steps. Likewise, the series capacitive
reactance matching section starts at a value of 0.1 ohms and goes to a
maximum value of 10000 ohms of capacitive reactance, regardless of
frequency. Each matching section control displays its current setting both
in ohms or milli-Siemens, as appropriate, and in component values, such as
microHenrys or picoFarads. The exception is Series Resistance, which
displays only in ohms. Each control also displays its "dial" or "counter"
setting between 0 and 250.

The matching sections that employ transmission lines (Stub Open, Stub
Shorted, and Series Transmission Line) still display their value in
electrical degrees and in meters, as in previous releases. However, note
that only "Stub Open" and Serial Transmission Line display their electrical
length in degrees directly in the spin control display, whereas the "Stub
Shorted" displays its electrical degrees below the spin control display
along with the length in meters. This peculiarity in "Stub Shorted" is in
order to make "Stub Shorted" behave the same as all other controls. Each of
the other controls starts with a value that has the least effect on the
existing impedance situation spins upwards to a value that has the greatest
effect. In order to accomplish that with a shorted stub, it is necessary to
start the shorted stub at its maximum (90 degrees) length and spin it up to
its shortest length (0 degrees).

Help File Improvements -
The Help File now includes topics on "Designing Pi Sections" and "Quick
Start". The "Quick Start" topic goes through a simple design of an L-Section
to match a high impedance, complex load to a 50 ohm source. It also goes
through a more difficult design using a series transmission line section to
create a match with a high impedance, complex load and a 300 ohm line. The
latter exercise is take directly from Chapter 28 of the ARRL Antenna Book,
17th Edition.

Tnx and 73,

Bob Lay (W9DMK), Dahlgren, VA
w9dmk at crosslink.net
Home Pages: http://www.qsl.net/w9dmk
http://zaffora.f2o.org/W9DMK/W9dmk.html
http://meltingpot.fortunecity.com/albania/784