This is only a preview of the January 2009 issue of Silicon Chip. You can view 31 of the 96 pages in the full issue, including the advertisments. For full access, purchase the issue for $10.00 or subscribe for access to the latest issues. Articles in this series:
Items relevant to "USB-Sensing Mains Power Switch":
Items relevant to "Remote Mains Relay Mk.2":
Items relevant to "Multi-Purpose Car Scrolling Display, Pt.2":
Items relevant to "433MHz UHF Remote Switch":
Purchase a printed copy of this issue for $10.00. |
The state-of-the-art in GPS:
Navman Platinum S300t
SatNav (GPS) units were one of the “hot” items at Christmas time.
Most were the low-cost, low-featured variety. But we wanted to see
what was offered in the top-of-the-range models and Navman came
to the party with their just-released “Platinum” S300t. About the
only thing it doesn’t have is the kitchen sink. Oh, did I miss that?
M
y main reason for visiting the
Sydney Motor Show back in
October was to get as much
information as possible on electric cars
– and in particular, the Chevy Volt (see
report in SILICON CHIP, December ’08)
Apart from that, I found the show
somewhat disappointing with quite a
number of manufacturers choosing not
to show (no pun intended!)
Sure, it was all glitz and glamour,
lots of bright lights and agonisingly
sparkling paintwork – but not much
in the way of substance, especially for
us and, therefore, readers of a technical
electronics magazine.
So I started to look for other items
of interest. Apart from a long, envious drool at the masterpiece of auto
engineering that Enzo Ferrari kindly
named after me (Testarossa, of course!)
and staring gobsmacked at a magnificently restored Ford GT with an
estimated auction price approaching
$300,000 (you could buy them for
less than $20,000 brand new!) there
really wasn’t much to hold my interest, at least.
As I was about to leave, I took
another look through the press kit
which organisers gave to members of
the media. It was mostly one PR blurb
after another, until I got to the Navman folder.
"What's this? A brand new GPS
unit?". My excitement lasted only a
by Ross Tester
few milliseconds when I realised that
it wasn’t a “real” GPS but unfortunately
only a case (yes, a real GPS case!)
with a weight inside it to simulate
the works.
There was also an invitation to visit
the Navman stand to see what all the
fuss was about with their new Platinum
range. I’m not sure the PR effort was all
that successful, as mine was the first
dummy GPS the people on the stand
had seen (and this was day 3!).
Anyway, the most helpful Navman
salesman took me through the features
of this new model and that was enough
to convince me that we should get hold
of one for review.
Why look at SatNav?
Let’s face it: SatNav (GPS) units are
JANUARY 2009 19
the proverbial “dime a dozen”. They’re
long past being a toy for the idle rich;
in fact, GPS units are now inbuilt into
many cars, ranging from the humble
daily drive to some very up-market
(read expensive!) marques.
For those who don’t have one built
in, the stuck-to-the-windscreen models are becoming ubiquitous. Just have
a look at the number of cars being
driven around these days with a GPS
hanging off the glass.
Police tell us that the windscreen
mount is a dead give-away for thieves
because 99% of people place their GPS
in the glovebox when they leave the
vehicle. Even if the glovebox is locked,
that’s only a few moments work with
a screwdriver.
The number of portable GPS units
has just taken a monumental increase
– with belt-tightening the order of the
day last Christmas, large Plasma and
LCD TVs took a hammering in the sales
departments but retailers reported GPS
units just about flying out the door.
Indeed, there were several GPS
units being advertised at prices seemingly impossible even last Christmas
– around $100 in some cases.
But these were/are, in the main, “old
technology” with 3.5-inch screens
and not much more than basic GPS
functions (eg, where am I, show me
how to get to “X”). We weren’t really
interested in these because they are
so common and just about everyone
understands how GPS works (if you
don’t, see the side box!)
But the Navman S300t Platinum
GPS was anything but “basic” – and we
thought our readers would like to see
what a state-of-the-art GPS unit offers,
albeit with a rather more significant
pricetag than sub-$100!
In fact, the platinum range have
recommended retail prices ranging
from $429 up to $699 for the unit
we played with. I don't think $699 is
the most expensive GPS unit on the
market these days but it would have
to go close.
So for this amount of money, you’d
want to get a lot more than basic GPS
functions, right? You do!
We’ll look at these in a bit more
detail shortly but first, let’s describe
the unit itself.
The first thing you notice about the
Platinum series is, unlike most GPS
units, the complete absence of buttons
on the front panel. That’s because the
myriad of controls have been migrated
to the touch screen. That screen, by the
way, now includes “glide touch” – you
navigate around the map or menus by
gliding your fingers over the screen.
That’s really neat.
Ignoring the absence of buttons,
the S300t looks not too dissimilar to
many of the other GPS units on the
market these days (I’m sure Navman
would argue with that!) but it’s only
after use that the differences become
apparent.
With a 4.3-inch “widescreen” it
measures 130 x 78mm and is just
13.5mm thick. Weight is 150g. It looks
identical to the three other S-series
(Platinum) models but it's the list of
features that places the S300T at the
top (at least currently) of Navman’s
evolutionary tree.
Released only last November, Navman claim the four models in the
Platinum series – and the S300t in
particular – represent the very latest in
satellite navigation technology.
As well as providing a lot more
"grunt" inside the case, importantly
they have simplified the user interface to just three key areas: “go” for
regular navigation instructions, “find”
to search for specific places, areas or
businesses and “explore” to search an
area in greater detail or pull up information about points of interest (POI)
online using TrueLocal.
Each in the range sport a 400MHz
processor with either 1GB or 2GB of
memory (the top two models have
2GB) and a micro-SD card slot.
Advanced features
In no particular order, just some of
the features offered by the S300t are:
• Live traffic updates using the SUNA
Traffic Message Channel (TMC).
Updates are provided continually
as road conditions are monitored,
including accidents, incidents and
traffic congestion. It will provide
the location, how long the likely
delay and even give you options to
detour you around the location. A
lifetime subscription to SUNA TMC
is included.
• Maps cover 100% of the population of Australia – over 1.1 million
kilometres of roads with shortcuts,
fuel, parking, places to eat, tourist
information and much more. The
maps are powered by Navteq and
Reproduced not far off life size, the Navman
S300t is shown here in its 3D mode with
major buildings and landmarks as you
would see them driving along – in this case,
Sydney's Town Hall and Queen Victoria
Building. Also on this screen is a traffic
warning from the SUNA TMC, showing
where the delay is and average speed.
The S300t is remarkable for the lack of
controls. In fact, there are two on the
front – the blue stripe (bottom right)
invokes the on-screen menu, which
basically controls every function and
setting. The pin (just visible top right)
allows you to "fix" a current position
so that you can return to it later. It's
a very handy feature when you are,
for example, looking for an address
in an strange area. The only other
control is the power switch on the
top of the unit. Almost hidden here
is the power connector on the
underside.
20 Silicon Chip
•
•
•
•
•
•
•
•
•
•
•
•
you can zoom the maps for greater
detail/greater area.
Tag location – if you want to remember where you were, or a particular
building/address, pressing a “pin”
icon on the screen records that location exactly, enabling you to return
(with GPS directions) at any time.
Bluetooth hands-free, which enables
you to go on line via Truelocal to do
searches of over one million listings.
You can also use the Navman as a
hands-free car kit for mobile phones
with Bluetooth.
FM Transmitter – the S300t (along
with the next model down, the
S200) features an FM transmitter
which operates through you car radio/stereo, so all voice and warning
tones come through that. MP3 music
files and even Bluetooth connected
phone calls also operate in this
way.
FM Radio Receiver – the same two
models also have an inbuilt receiver
for FM radio stations which also
operate through the transmitter to
the car stereo.
Automatic day/night screen switching
Lane guidance and junction views
– no longer will you be caught in
the wrong lane to make a turn or
heading.
3D landmarks – if you’re in a strange
city, major buildings/landmarks
(such as the Sydney Opera House
or the MCG) appear in 3D that fit
the dimensions of the map, making
recognition that much easier.
Digital log book – store distance
expenses, etc
Efficiency mode – it can give directions that avoid braking and keep
speeds constant, reducing petrol
consumption.
Explore – hundreds of thousands of
points of interest are programmed
in but the Navman allows you to
go much further by connecting to
TrueLocal to look up more information, even dial them up or be guided
directly there.
Warnings – speed cameras, red
light cameras, accident blackspots,
railway crossing and school zones
are all highlighted as you drive
along. Speed zones also give you
the warning for change of speed
(unfortunately, not time related so
it will still say 40km/h at midnight!)
Pedestrian mode – swap to this
mode and you'll get directions for
In its "Explore" mode
you can do just that
– not just with the
hundreds of thousands
of POIs loaded but you
can also connect to
TrueLocal and use the
huge database to find
what you want. It will
then direct you there
or, with a bluetooth
phone paired, you can
then call up hands-free!
travelling on foot, including blocked
access, turn restrictions, etc.
• Overseas maps – Eastern and Western Europe, USA, New Zealand and
Canada are already contained in the
box (you do need to purchase an
unlock key).
• NavPix Downloads – you can download geo-tagged images from Flickr
(or from Navman website) and go!
• Micro SD card slot – with this you
can view pictures or even videos or
play MP3s (said to be great for the
children on long trips – but isn’t that
where you’d want the GPS operating?)
I'm sure there are more features that
I didn't find out about in the short time
I had to play with the Navman but
you'd have to agree, this list is pretty
extensive.
Digital map updates
The Navteq digital map data bears
special mention. They claim to have
the largest field team of geographic
analysts in Australia who continually update the maps with both local
knowledge and contacts. They collect
data on new roads, one-way streets,
turn restrictions, physical barriers,
new housing developments and points
of interest including banks/ATMs,
petrol stations, restaurants, hotels and
shopping centres.
In use
The basic operation of the Navman
S300t is very easy to get going and
use –eg, telling you where you are and
how to get to where you want to go.
The Australian female voice (Karen)
was much more pleasant than that of
my own GPS (sometimes I’d love to
throttle Jane and occasionally [electronically] do!) You can also have an
Aussie male, Lee.
But if you spend as much on a GPS
as the Navman S300t, or even any of
the platinum range, you’re going to
want to use a lot more than the basic
SatNav functions – in other words,
some of the myriad of features it comes
packed with.
I have to say that some of the “premium safety alerts” – school zones,
accident black spots, red light and
speed cameras, etc – I found not only
a nuisance (yes, they can be turned
off!) but I also often found them inaccurate.
For example, it several times insisted I was coming to a school zone
when there was none. Once it said
there was a school zone 250m ahead
when I was driving down a 150m deadend street where there was definitely
no school, or any school in the general
direction. (There was a school perhaps
500m behind me – was this the one it
was referring to?)
Another time it told me there was a
school zone ahead in 300m, no 350, no
400m . . . all the way to 550m when it
decided there was no school anyway.
A few hundred metres later, I turned a
corner and drove for 200m alongside a
school that has been there since Adam
and has school zones on three sides.
. . and no school zone showed at all.
It also insisted there was a “safety
camera” ahead, after I had passed it by
it on a parallel road. Not only is that
annoying, if you are in an unknown
area your concentration is not what
it should be when you’re continually
looking for revenue raisers (woops –
forgive my cynicism showing through)
– in this case non-existent ones.
I also found it was often inaccurate
in its reported position – whether this
was me not having learned enough
about the unit I’m not convinced – but
it sometimes told me I was tens, and
sometimes hundreds of metres away
from where I knew I was. Loss of GPS
JANUARY 2009 21
How the Global Positioning System Works
L
ike many of today’s technology breakthroughs,
GPS was originally a military system. Initially four
NAVSTAR satellites, the first launched in 1978,
formed the backbone of the system. As satellites go, they
aren’t very big: about 1.5m wide and 5m long. In orbit
(17,450km out), they weigh only 850kg.
Each satellite contains four extremely accurate atomic
clocks (one second in three million years!). This time information and satellite identification is transmitted on two
L-band carriers around 1.575GHz.
Today there are 32 of these satellites which provide
coverage to every point on the planet. At least three satellites would normally be “visible” from anywhere; more
important areas have up to twelve satellites available from
was used extensively to obtain positions in completely
which to obtain data.
featureless desert and often in blinding sandstorms. In
Because the exact position of each satellite is known fact, GPS has been credited with having a decisive role
at any instant in time, a GPS receiver on the ground (or
in the UN forces’ success.
in the air, or at sea) can work out precisely how far away
Most of today’s GPS receivers require an initial “fix” from
that satellite is by comparing the time-stamped transmitted
no more than three satellites to establish their position.
signal to the time it actually received that signal.
Once the signal is received and position determined, it can
Doing the same thing with the signal from a second
keep accurate readings using only one satellite. Therefore
satellite enables the GPS receiver to determine its position
it is ideal in very poor signal areas.
between the two. Adding a third signal enables a location
It can take almost a minute to receive and analyse
to be established; ie, a three-dimensional “fix”.
enough signals to determine position from a “cold start”.
And adding a fourth signal (or more) enables errors to Once the receiver knows where it is, a “hot start” gives a
be virtually eliminated, giving even more accuracy.
position in about eight seconds. While operating,
Design accuracy is within 30 metres of true
the information is updated about every 100ms.
position. Until 2000, accuracy for civilian and
While the majority of GPS units are fully selfnon-US-ally users was only 100m because of
contained, some have the ability to output
“selective availability” or SA errors, deliberately
data for recording, further analysis, etc.
introduced into the system to make it more
The output from the module is data in
difficult for non-friendly armed forces
the form of NMEA-0183 sentences.
to use.
NMEA stands for the National
But former US President
Marine Electronics Association
Clinton ordered SA be reand has become the standard for
moved on 1st May 2000, to
all GPS data output. An NMEA
allow all users access to the
sentence contains an address
military-precision signal.
field, a data field and a checksum.
Achieved accuracy is usuWithin the data field can be such
ally better than 30m and often
information as latitude and longisignificantly better – most
tude, north or south of equator,
Basic Positioning (simplified to one plane
vehicle GPS systems can
east or west of 0° meridian, speed
only): if the GPS receiver (at point A) knows
show exactly where a vehicle
over ground in knots, course over
it is a certain time away from the red satellite,
is on the road to within a few
ground in degrees true, the date
it must be somewhere on the red circle.
metres, an accuracy of at
and time, and whether the data is
Similarly, if it also knows it is a certain time
least 5m or even better. That’s
vaild or not.
away from the blue satellite, it can only be
where the red and blue circles intersect (points
not too bad from 17,450km
By the way, the reason that the
A & C). If a third (green) satellite is added, it
away!
exact positions of the GPS satelcan only be at point A. Once it knows it is at
The GPS system is fairly
lites is always known is that they
point A, even if the GPS receiver temporarily
unaffected by weather; rain
themselves use signals from the
loses data from one or two satellites it knows it other satellites to exactly deterand cloud generally have litcannot be at points B, C or D so it takes its data
tle impact but wet foliage and
mine their own position.
from one satellite and works with that data
even dense tree cover can
And positioning is not the only
until another comes into view. In the real GPS
cause problems.
use
for GPS: its highly accurate
world, all of the circles are actually spheres,
During the “Desert Storm”
time signals are used in a huge
so the system operates in all three dimensions
war in the Middle East GPS
variety of applications worldwide.
and can therefore give height.
22 Silicon Chip
signal? I don’t think so, given where I
was at the time – with an open, clear
sky view. And no, I was neither lost
nor inebriated!
Most of the time, though, it was dead
accurate, as you would expect. But the
inconsistency disturbs me.
I never had the opportunity for it to
re-plot my way around an accident,
as the only accident I saw in the time
I had it was just a few tens of metres
from the SILICON CHIP office – and
there was no way to go another route!
However, that feature in itself would
be one of the more handy to have if
you are on the road a lot and/or have
deadlines to meet.
And I didn’t try the unit in its “pedestrian” mode, even though this is
very easy to invoke. (Hey, why walk
when you can drive?)
The display
I found the daytime display too
“pastel” for my liking – I much preferred the night-time display, which
automatically switches over if set
that way.
You can adjust the brightness of the
display in both day and night – even
with the daytime display at 100% it
was not the easiest to see in bright light
and even worse in direct sunshine.
Conclusion
The Navman S300t has the most
amazing array of highly desirable
features I have ever seen in any SatNav unit.
But personally, that’s perhaps where
I had the most difficulty with it.
Like most technology products these
days, in the hands of a ten-year-old, I’m
sure every one of those features would
be understood and functioning very,
very quickly.
Despite the assurances of Navman
that they had simplified the user interface from previous models, despite
me having used a GPS for a year or so,
I found the learning curve a little steep.
Maybe it is because I have used another
brand of GPS and am very comfortable
with it that I had to “unlearn” a lot to
learn the Navman S300t.
Is that just me? Without wanting
to sound boastful, as a person who
lives “technical” 24/7, I believe I can
come to grips with most “technical”
products at least a little quicker than
the average man-in-the-street.
So if you buy yourself a Navman
S300t, you will be amazed at the range
of features it offers – but be prepared
to spend time getting to know it.
Or find yourself a friendly ten-yearold to explain it all to you!
Where from, how much:
Navman GPS units are available
from specialist retailers, department
stores and dealers throughout the
country, or online via www.navman.
com.au
The model reviewed, the Navman
Platinum S300t, has a recommended
retail price of $699 but before Christmas we saw them retailing at up to $50
or so less than this. The entry-level
Platinum model, the S100, has an RRP
of $429, with others retailing for $499
(S150) and $599 (S200).
The main differences between the
S100 and S300t are less memory (1GB),
no Bluetooth (therefore no live local
search either), FM transmitter, 3D
Landmarks or 3D junction view, no
MP3 or video player capability nor FM
Radio receiver and the SUNA TMC is
optional. The two others in the range
have varying levels of these features.
Otherwise, as we mentioned, they are
SC
identical in appearance.
Radio, Television & Hobbies: the COMPLETE archive on DVD
YES!
NA
R
MO E THA URY
ENT
QUARTER C NICS
O
OF ELECTR !
Y
R
O
T
IS
H
This remarkable collection of PDFs covers every issue of R & H, as it was known from
the beginning (April 1939 – price sixpence!) right through to the final edition of R, TV & H
in March 1965, before it disappeared forever with the change of name to EA.
For the first time ever, complete and in one handy DVD, every article and every issue
is covered.
If you’re an old timer (or even young timer!) into vintage radio, it doesn’t get much more
vintage than this. If you’re a student of history, this archive gives an extraordinary insight into
the amazing breakthroughs made in radio and electronics technology following the war years.
And speaking of the war years, R & H had some of the best propaganda imaginable!
Even if you’re just an electronics dabbler, there’s something here to interest you.
• Every issue individually archived, by month and year
• Complete with index for each year
• A must-have for everyone interested in electronics
Please note: this archive is in PDF format on DVD for PC.
Your computer will need a DVD-ROM or DVD-recorder (not a CD!)
and Acrobat Reader V6 (free download) to enable you to view this archive.
This DVD is NOT playable through a standard A/V-type DVD player.
ONLY
62
Exclusive toSILICON CHIP
$
+
$
00
7 P&P
HERE’S HOW TO ORDER YOUR COPY:
BY PHONE:*
(02) 9939 3295
9-4 Mon-Fri
BY FAX:#
(02) 9939 2648
24 Hours 7 Days
<at>
BY EMAIL:#
silchip<at>siliconchip.com.au
24 Hours 7 Days
BY MAIL:#
PO Box 139,
Collaroy NSW 2097
* Please have your credit card handy! # Don’t forget to include your name, address, phone no and credit card details.
BY INTERNET:^
siliconchip.com.au
24 Hours 7 Days
^ You will be prompted for required information
JANUARY 2009 23
|