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SERVICEMAN'S LOG
How friendly is “user friendly”?
How friendly is “user friendly”? That question
was prompted by recent cases of customer
confusion, caused mainly by technologies that
were supposedly designed to overcome user
difficulties with earlier designs.
One product that causes a great deal
of user difficulty is the VCR. They’ve
been around for many years now but
a surprising percentage of users still
have trouble programming the timer.
They can manage to record a program
if they are present when it is being
broadcast but setting it up for a late
night movie, or for a favourite sitcom
that clashes with a dental appointment, is completely beyond them.
As a result, one of the major features
of the VCR – and for which they paid
good money – is lost.
Unfortunately, efforts to overcome
these problems don’t always help. On
the contrary, they often seem to make
things worse. And on top of this, makers keep loading on more and more
features, most of which will never
be used anyway and which only add
further confusion to the scene.
Of course it is easy enough to sneer
at “user ineptitude”. But is this fair?
The average user doesn’t have a degree
in electronics or even a smattering of
the discipline. Nor should they have
to. It is time we stopped building confusion into these appliances.
What started all this? The sudden
realisation that, as a serviceman, I
am being called on more and more to
Fig.1: this
circuit shows
the controller IC
(IC001) in the
Sony KV-2183AS
colour TV set.
This receives
instructions from
the IF unit (IF201)
via pins 10 & 11
(AFTD, AFTU).
solve problems which don’t involve
any mechanical or electronic failure.
In
stead, they are simply problems
caused by user confusion.
The largest area where these problems occur involves channel selection
and remote control. Let’s look at a
couple of typical cases. The first one
involved a Sony TV set, a KV-2183AS,
owned by one of my lady customers.
Her complaint was that, since her
grandson had come to stay with her
she couldn’t receive channel 9 any
more and when she tried to restore it,
she lost channel 7 as well.
The Sony, like most modern sets,
uses an automatic search system to
set it up for the wanted channels. The
user puts it into the search mode and
it scans the band(s) until it finds a
channel. The user then has the option
of putting that channel into memory
or bypassing it.
Either way, the system then scans
for the next channel and presents the
same option. This procedure is repeated until all the wanted channels have
been memorised and are ready to be
recalled at the touch of a button.
Willie did it
Well, there are no prizes for guessing
what had happened in this case and
the lady had been honest enough to
admit to it, which is more than I can
say for some customers. Little Willie
had had a bit of a fiddle and made a
mess of things.
Anyway, I didn’t imagine it would
be anything more than a routine job.
How wrong can you be! I pressed the
programming buttons and the system
went into search mode. But, instead of
stopping as it reached each channel,
it shot straight through and just kept
on searching, repeatedly going around
and around through all the bands.
However, in a seeming contradiction,
the remaining channels – 2, 10 and
SBS) were still locked in memory and
could be called up.
I wasn’t quite sure where to start, a
November 1995 69
Fig.2: the IF unit in the Sony KV-2183AS drives the controller IC (IC001)
from pins 5 (AFT DN) and 4 (AFT UP).
factor not helped by the fact that access
to the appropriate PC boards leaves a
lot to be desired. But the circuit suggested two suspects: (1) the controller
IC (IC001 – M50431-611SP), which
controls most of the set’s operational
functions; and (2) the IF board (IF201
– IFB-368), which supplies some of the
information to the controller.
I picked the IF board as my first
choice, if only because it was the
easier option. The controller IC is a
42-pin device, whereas the IF board
has only 12 pins. But, more than that,
the IC was a relatively low risk device,
while this IF board has something of
a reputation.
The complete assembly, in a metal
can, carries a Mitsumi brandname and
is used in several makes of sets. No
circuit is available and it is described
as being non-serviceable. Three of its
terminals – 4 (AFT UP), 5 (AFT-DN)
and 1 (RF AGC) – feed data to the
controller.
The works consist of a small PC
board carrying an IC, coils, ceramic
filters and some transistors. And the
reputation, as you might have guessed,
is for dry joints. Well, at least that
aspect of it is serviceable, so I pulled
it out and examined it. There were
several obvious dry joints around
the filters, which I fixed first. I then
reworked the rest of the board. After
all, once you get that far, there’s not
much point in mucking about.
Having done that, I refitted it and
tried again. And that was it; it worked
perfectly, stopping at every station. I
reprogrammed it for the missing channels and the job was done.
So everyone was happy. Well, more
or less. While the lady was happy to
have the set going again, it had cost
her a service call and she must have
wished that Little Willie had kept his
fingers to himself. I hope the error of
his ways was pointed out to him.
OK, so there was a genuine technical failure, although it wouldn’t
have mattered if Little Willie had left
things alone. But the episode shows
that making it easy to select and store
channels can make it just as easy, or
even easier, to foul things up.
Remember the turret tuners in the
early TV sets? The user couldn’t muck
about with those. Granted, they were
expensive and mechanically vulnerable and nobody really mourned their
replacement with electronic tuning.
But I wonder if the electronic systems
could be made a bit more secure?
The complicated NAD
That Sony episode was really just
a minor hiccup compared with the
next story, which occurred shortly
afterwards. The customer was a Greek
gentleman who, unfortunately, had
only a limited command of English.
Even so, his command of English
was far better than my command of
Greek. Which made communication
somewhat difficult.
And we needed all the communications skills we could muster because
his problem was a difficult one – a lot
more difficult than he realised, in fact.
However, with patience, the story
eventually evolved. It transpired that
he had purchased a NAD stereo TV set
and VCR in a knockdown/job-lot deal
from a highly respected company that
was closing down after 30 odd years
trading in Australia. And he wanted
me to come around to his house and
sort out some problems.
70 Silicon Chip
In greater detail, the TV set was a
NAD Monitor, which is really a rebadged ITT-Nokia 7163VT. These sets
are made by Nokia Consumer Electronics, a very large Finnish company,
which also makes sets under the Akai,
ITT, Luxor and Salora labels. They also
make mobile telephones and other
electronic appliances.
So what did I have to sort out? There
were two problems really. One was
that the set had been programmed
for some stations but not all, and the
owner had no idea of how to go about
doing this job himself. The other problem was harder to pin down initially
but, by gestures, he indicated that the
top of the picture was flicking back
and forth; ie, flag-waving. However,
this apparently only occurred when
the set was working from a VCR, an
important point as it turned out.
My experience with European sets
in general, and the Nokia family in
particular, has been strictly limited;
little more than secondhand from
colleagues. But I had learned enough
to know that they can be significantly different from the American and
Asian designs with which we are most
familiar.
I was also aware that this was an
upmarket model, featuring a whole
host of features, But just how many
I wasn’t to realise fully until much
later. In fact, it is a multi-standard
type –PAL, SECAM, NTSC – with
provision for all the minor variations
of these standards which occur from
country to country.
It also features stereo sound/dual
language facilities (again with variations to suit different standards),
digital sound (NICAM), Videotext and
Teletext (with a wide range of options).
And, in addition to the usual video
recorder facilities, it can also handle a
video disc player, video games, a pay
TV decoder, a video camera, a computer and tape recorders. And so on.
No instruction book
Of course, the owner didn’t have an
instruction book and that settled it;
there was no way I was going to tackle
a problem like that in-house.
From what little I do know about
European sets, I can’t escape the impression that, if there is a hard way to
do something, they’ll find it. Anyway, I
managed to explain that he would have
to bring the set to the shop and that I
might need it for some time.
And so it eventually landed on
my bench. But where should I start?
There were no controls on the set, as
everything was done via the control
unit. And it was a control unit the
like of which I had never seen before,
though I’d previously heard about it.
It is called a “TV Mouse” control – a
supposedly impressive term obviously
derived from the computer scene.
So the first thing I had to do was
learn how to use this device. My
knowledge of mouses – er, these devices – is limited but I imagined there
would be a ball on the underside, the
kind of thing that is used to move a
cursor around a computer screen. But
there was nothing like this; it looked
like a fairly standard control unit,
though with a lot more buttons than
most. The accompanying drawing
will give the reader some idea (I only
acquired this diagram much later).
OK, let’s suppose I could work out
how to use it. This should allow me to
program in all the local channels and
solve that problem. But what about
the flag waving?
In the normal way of things,
flag waving suggests a fault in the
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November 1995 71
Fig.3: this diagram shows the
front panel of the “mouse”
remote control unit used with
the Nokia 7163 colour TV set.
The mouse function was not
immediately obvious and the
use of symbols and colours for
some of the buttons didn’t offer
much help when it came to
using the device.
horizontal flywheel sync system,
particularly involving the flywheel
time constant. So one might be
tempted to pull the chassis out, find
the appropriate section, and start
troubleshooting – all this without the
benefit of a circuit, at least initially.
But, as I hinted earlier, European
72 Silicon Chip
sets are different. Apparently, they
find it necessary to provide a choice
of flywheel time constants: long for
off-air operation (particularly in fringe
area situations) and short for VCR
operation. I have no idea why this
is so, particularly as American and
Asian designs seem able to achieve
a compromise setting which is quite
satisfactory for both conditions.
But that’s the way it is. And it
meant that this set almost certainly
would have this facility. And there
was, therefore, little point in assuming a fault and pulling the set apart,
if it was just a matter of resetting this
adjustment. But, once again, I was at
the mercy of the control unit, because
any such adjustment would have to be
made through it.
As readers can imagine, with nothing more than an array of buttons on a
control unit, and no other data, it was
a formidable situation. And, to make
matters worse, not all the buttons are
clearly identified. While most are
marked with words or numbers, the
top four carry symbols and the four
beneath them have both symbols and
colours (the colour sequence, from
left to right, is red, green, yellow and
blue). Three other buttons, two below
the numerical buttons and the other in
the bottom righthand corner, also carry
symbols only. Talk about starting from
behind scratch!
I switched the set on and it came
up on one of the channels to which
it had already been preset. I took a
punt and pressed the menu button.
This brought up a selection of menus
and, after a lot of trial and error (read
muckin’ about), I realised that all the
menus –and there is a swag of them –
can be presented in no less than nine
languages. Unfortunately, Greek is
not among them but, fortunately, the
system had already been programmed
for English.
Pressing the video button brought
up a menu offering colour (saturation),
brightness, contrast and sharpness
functions. Similarly, the audio button
produced a menu offering stereo, hypersonic on, bass, treble, balance and
volume – each with its own bargraph
display for reference.
The menus are presented as white
characters on a black background, similar to some computer presentations.
The exception here is the item that’s
currently selected, which will have the
reverse presentation; ie, black charac-
ters on a white background (typically
referred to as the “cursor”).
All that was fine as far as it went. But
how did one move the cursor to change
the selection and, having changed it,
activate it? I found the answer quite
by accident. I noticed that moving the
control unit sometimes produced a
sound from inside it and, at the same
time, I realised that the cursor on the
menu had changed.
So this was their version of a mouse;
a loaded contact ball inside the control which moved when the control
was pointed up or down, or banked
to the right or left. And, logically, the
cursor moved up when the front of the
control was lifted and down when it
was depressed.
For example, when in the audio
menu, one could select, say, volume
and then vary the volume up or down
by rotating or banking the control to
the left or right. Or one could select,
say, brightness in the video menu and
vary it in a similar manner.
I was starting to get the hang of
the thing now. But it was only the
beginning; it was to take a lot more
“muckin’ about” before the job was
done. And it would be virtually
impossible to set out all the things
that can be done with this system or,
indeed, how I worked out how to do
them. We’d be here forever. In any
case, I doubt whether the reader could
follow it all, without the benefit of a
hands-on approach.
But I did make some notes as I
worked out what I needed to do, just
in case I had to do it again. These will
give the reader some idea of what is
involved.
First, the tuning. Press the MENU
button, then the blue button, to bring
up MENU 1. Move the cursor to
TV-PROGR and call up MENU 2 by
rotating the mouse control. This gives
a choice of tuning approaches:
(1). The channel number mode. A
number of frequencies are pre-programmed into the set – useful only if a
list of channel frequencies is available.
Enter a channel number – assuming
that one is available to suit an Australian transmission. No channel list
available. Resorted to search mode.
(2). The search mode. Press the
green button to change from channel
mode to frequency mode. Press the
MENU button and rotate the mouse to
search for stations. When a station is
found, revert to the channel mode to
What about the user?
And one has to admit that it is all
extremely clever and ingenious. But
how does it sit with the average user?
Is he or she really expected to program
such a complicated device? Among
other things, they would have to select
the appropriate TV system, find and
store all the TV channels, consult and
use the video adjustments and options,
and carry out the sound adjustment
options.
In most cases, of course, a dealer
would have already made the adjustments and the set would be ready to
go on installation. The catch comes if
the system has to be reprogrammed for
any reason (eg, if the user moves to a
different location). The reality is that
they usually have to call in the likes
of yours truly to do the job for them.
And that costs money.
Finally, there is the vulnerability of
these systems by reason of all adjustments being accessible via the remote
control. A careless user, or an inquisitive Little Willie, can wreck a long and
complex programming sequence in a
few seconds. Again, that costs money.
So what’s the answer? I don’t know – I
can only see the problem. And it’s a
SC
very real one.
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allocate a number for it. It can also be
given a name, if desired; eg, “Channel
7”, or “SBS”, etc. Save by pressing the
red button.
So, by this process, all the local
channels were eventually located,
stored, numbered and named. Then it
was to the flag- waving problem. This
was fixed as follows:
Press MENU button. Brings up
INDEX menu. Press blue button.
Brings up sub-menu listing SAT-PROGR, TV-PROGR, EXT-PROGR. Select
EXT-PROGR. Brings up sub-program
listing, among other functions, SYNCHR-VCR. Select the latter. Rotate
control to switch to long time constant.
And that was it; problem solved. It
sounds easy when you say it quickly
but it wasn’t easy, of course. It took
many hours – and much colourful language – before the two above routines
were worked out and completed.
But by the time I had done it all, I
realised that I was beginning to enjoy
the challenge; that, in fact, I was being
sucked in by the technology and the
ingenuity behind it – much as I suspect
the engineers who designed it were
sucked in.
November 1995 73
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