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A nostalgic look
Colour TV in Aus
Last month, we looked at some of the interesting changes that the
introduction of colour TV brought to the service industry some 30 years
ago. This month, we’re looking at some of those “interesting” locallymade colour TV sets . . . then again, for those in the industry at that
time (and since), the word “interesting” is not the first adjective you’d
use!
B
EFORE THE WHITLAM Labor
government announced sweeping changes to the tariff systems
covering imported manufactured
goods and components, there was
a general agreement in the industry
that colour TV sets would cost somewhere between $1200 and $1500 (ie,
approximately 10 times the average
gross weekly wage!). Moreover, there
would probably be no more than five
basic chassis designs: Philips, Sanyo,
Panasonic, Thorn and Pye.
Of course, the changes to the tariff
structure changed this drastically and
these prices were drastically revised.
In a bid to level the playing field a bit,
Telefunken, the owners of the PAL patents, enforced a 6-month moratorium
on the direct importation of colour
sets with screen sizes of 51cm or less,
from the date the first official “limited”
broadcasts started in late 1974.
36 Silicon Chip
The locally manufactured line-up
for 1974 consisted of the Philips K9,
the Kriesler 59-01 (basically an electronic clone of the K9 but with different board layouts), the AWA/Thorn
4KA (an antipodean-ised version of
the UK “hot chassis” Thorn 4000 series), the Panasonic 2000 chassis, the
Sanyo CTP7601, the HMV C210, the
PYE CT25 and the Rank Arena (NEC)
2601 and 2201.
Notably absent were any locallymade models with remote control,
absurd though that may sound now.
The problem was that remote control necessitates a varicap tuner and
because Australia has a number of
“oddball” TV channel frequencies
that are not used anywhere else in
the world, there was nothing available
that could tune in all the Australian
channels. There were some up-market
fully-imported European models that
did offer remote control but sales-wise
they were problematic, because you
couldn’t guarantee they would work
everywhere.
The first remote controls used ultrasonic transducers and were big,
clumsy and unreliable. It wasn’t until
the appearance of infrared models in
the 1980s that they started to become
standard equipment.
Philips/Kriesler
The Philips K9 was a fascinating
mixture of the antiquated and the futuristic. It featured a choice of 56cm
and 66cm 110° delta-gun tubes, with
an incredibly comprehensive convergence panel. When this worked, it gave
very good results indeed and in fact
K9s were widely used in TV studios
as inexpensive substitutes for “studio”
monitors. Sadly, its very complexity
was also its downfall. It was the same
siliconchip.com.au
at the start of
P a r t 2 : B y K e i t h W a l ters
stralia
old story – the more things you put in,
the more things there are to go wrong!
Nonetheless, a fully-working 66cm K9
forms part of my “living museum”!
The video drive to the picture tube
used the “colour difference principle” – ie, a high-voltage luminance
signal was fed in parallel to the three
cathodes, while separate R-Y, G-Y and
B-Y signals were fed to the appropriate
control grids. Although this was common practice with earlier all-valve
colour TV sets overseas, the K9 was
the only mass-market all-solid state
design I am aware of that used this
technique.
Some time before this, Philips had
decreed that the way of the future was
highly “modular” chassis design, with
most of the active circuitry contained
in small plug-in units reminiscent of
the “motherboard/expansion board”
approach of PCs. You weren’t supposed to try to repair them and none
of the Philips circuit manuals included
schematics of any modules used.
The K9 used a large number of these
modules and naturally they wanted to
charge an arm and a leg for replacements! Fortunately, Kriesler (owned by
Philips) used a similar module system
with almost identical circuitry and pin
layout but their modules were physisiliconchip.com.au
cally larger and meant to be serviced.
More importantly, Kriesler included
the module circuits in their manuals,
which were “close enough” to the
Philips ones!
Like many of the other locallymade designs, the K9 also featured
something else new and frightening: a
switchmode power supply. Although
all TV sets made these days (as well
as VCRs and DVD players) use that
technique, in 1974 this was something
we’d only read about in English TV
servicing magazines and then with
reference to only one TV chassis – the
Thorn 3000 series!
When it’s all said and done, the
Philips engineers got it mostly right
with the K9, since as far as the power
supply and deflection systems go,
modern colour TV sets are remarkably
similar to the classic Philips design,
albeit with most of the discrete transistors now packaged into ICs. The Australian version of the K9 was unusual
in that, while the power supply itself
was “hot”, it had an isolated secondary
winding, which meant the rest of the
chassis was “cold”. With the modern
requirement for direct A/V inputs,
this is standard practice now but the
original Dutch version of the K9 had
a hot chassis.
The Kriesler models were basically
very similar to the K9, although they’d
dispensed with the colour difference
drive and just used direct RGB drive
to the tube. Kriesler also specialised in
the manufacture of “prestige” models
with elaborate teak veneer cabinets.
Some of these cabinets were so good
that a friend of mine used to make
extra money “refurbishing” them for
a large department store, basically by
“retro-fitting” them with the innards
of a modern plastic-cabinet TV!
And now for something
completely different . . .
Then I suppose if you want to go
from the sublime to the ridiculous, we
also had the HMV C210. Unlike the
K9, this was a veritable tour de force
of dead-end design, in particular the
use of a Thyristor-based horizontal
deflection system.
The story behind this technique is
quite fascinating and not terribly well
known. First of all, in most countries,
the bulk of valve TV sets did not use
power transformers, a tradition the
manufacturers were keen to maintain
with their solid-state designs. The
valve heaters were connected in series
directly to the mains through a suitable “ballast” resistor and (usually)
April 2005 37
Many of the early
colour TV sets
were real pieces
of furniture, built
to quite high
standards of
joinery. This AWA
set (sorry, AWA
Deep Image Colour
set – what ever that
meant!) was typical
of the genre.
the 200V or so main HT line was derived by half-wave rectification on the
mains. (You may have read about valve
radios being configured the same way
in the vintage radio column).
With any “conventional” horizontal
deflection system, (ie, using either a
pentode valve or a bipolar transistor
as a 15,625Hz switch), there is an
approximate 10:1 correspondence
between the HT rail voltage used and
the flyback pulse generated across the
switching device. For example, a 100V
supply rail will produce 1000V flyback
pulses, 120V will produce 1200V flyback pulses and so on.
It’s no trouble to produce power
valves with breakdown voltages of
thousands of volts, so they could be
run more or less directly off rectified 240V mains. In fact, most valve
horizontal stages used a so-called
“HT Boost” circuit where the input
HT voltage was stepped up to 500V
or so by the horizontal damper diode.
This had a number of advantages but
in particular, manipulation of the grid
bias of the output valve allowed the
boosted HT rail voltage to be regulated by a feedback loop, which both
stabilised the width and filtered out
any residual mains ripple. They were
in fact an early form of switchmode
power supply.
Unfortunately, this approach is not
possible with transistors. There is a
definite technological brick-wall you
run into with silicon which makes it
impractical to manufacture transistors
with breakdown ratings much above
1500V.
This means that the maximum sup38 Silicon Chip
ply rail voltage is limited to around
150-160V. This was all perfectly splendid with the US 117V AC mains, since
that voltage could be directly rectified
and filtered to produce around 150V
DC, which could then be regulated
down to 110-120V, giving a comfortable 1200V flyback.
Thus most US and Japanese sets
were “hot chassis” designs, often using
a simple linear series regulator.
With European 220/240V mains
voltages, this was not possible. The
raw rectified DC would be something
over 300V; getting this down to 150V or
so with a linear regulator at the typical
current of 1A would give a dissipation
of around 150W! Some manufacturers
experimented with using two 1500V
horizontal output transistors in series
but this was a tricky and expensive
option.
The most common approach in
Europe was to use a single thyristor
as both half-wave mains rectifier and
voltage regulator, which worked on
much the same principle as a light
dimmer. The thyristor simply held off
conducting until the positive mains
cycle had passed its peak and dropped
back to around 170V or so.
Although these worked well enough,
the various electrical authorities
weren’t too thrilled about the way
they chopped up the mains waveform,
and so the manufacturers, particularly
those with a sizeable export market,
began to look for alternatives.
The Japanese for the most part took
a pragmatic approach and simply fitted
their European export models with
stepdown transformers. This allowed
them to retain their tried and proven
series regulators and in fact, their European designs weren’t all that different
from their NTSC models.
Philips, as mentioned earlier, went
for the new-fangled switchmode power supply, while others tried a more
exotic approach, using a Thyristorbased horizontal deflection developed
by RCA in the mid 1960s.
The full operation of a Thyristor
(SCR) based horizontal deflection
system is extremely complex but essentially, the energy is fed into the
deflection yoke during the flyback
period, something in the manner of a
Capacitor Discharge Ignition system.
The yoke winding then essentially
“coasts” through the visible scan
period, using a network of switching
diodes and a second SCR to produce
an approximation of a sawtooth scanning current.
In the 1960s, there was considerable
doubt over whether it was even possible to manufacture silicon transistors
with a breakdown rating of much over
500V, so for a while it seemed that the
only practical way of making an allsolid-state colour TV chassis was to
use a big (and heavy) mains stepdown
transformer.
RCA’s SCR horizontal deflection
system was first demonstrated in 1967,
as a possible solution to this problem.
An unregulated +140V HT line derived
directly from the 117V mains was fed
to the flyback Thyristor via a saturable
reactor, which basically formed the
control element of an electronic regulator system. Without going into too
many details, flyback pulses of about
120V amplitude were applied to the
horizontal deflection yoke, resulting in
a peak-to-peak scan voltage of about
24V. This operation is basically the
reverse of that of a conventional line
output stage.
Although the system did work,
it never caught on for a number of
reasons. First of all, although the
basic principle was simple enough,
the actual circuitry needed was quite
complex, requiring several large ferrite
inductors and high-value polyester
capacitors.
Because of the very low scanning
voltage used, the yoke current peaked
at over 100A in large-screen sets,
which meant extreme care was needed
in manufacture to avoid dry solder
joints, as the slightest resistance would
result in major burn-ups. There were
siliconchip.com.au
also severe problems with “spooks”
(line frequency harmonics) causing
interference on the screen.
Ironically, it was RCA themselves
who finally sealed the fate of the
original system, when in the late
1960s their semiconductor division
managed to produce power transistors
with a 1500V rating, using a design
not all that different from what is still
standard today. US (and Japanese)
solid-state designs thereafter tended
to use bipolar transistors with a linear
regulated power supply.
However in Europe, the SCR line
output stage was re-invented in the
early 1970s, with a new three-SCR
design. This also was designed to run
from filtered but unregulated mainsderived DC (this time from 220-240V
mains) but in this case, a special
flyback circuit stepped this voltage
up to somewhere between 450V and
600V. The third SCR regulated this
boosted voltage by bleeding a variable
proportion of it back into the main unregulated supply during the horizontal
scanning period.
The revised system worked on
much the same principle as the earlier RCA one but because it applied
higher voltage flyback pulses, a more
conventional (cheaper) yoke design
could be used. However, the Australian HMV C210 would have to take the
biscuit as an example of taking the
worst features of two technologies and
combining them!
The C210 used the old-fashioned
two-SCR design but they also used
a switch mode power supply, which
meant the main feature of the SCR
design – the built-in voltage regulator
function – wasn’t actually used! The
lack of a boosted HT rail also meant
that they had to revert to a special
low-impedance scanning yoke, with
all the inherent problems of heavy
circulating scan currents, dry joints
and so on.
Worse still, for the switchmode
power supply, they chose a peculiar
self-oscillating design which, while
economical to build, was barely good
enough to drive a set with a conventional transistor horizontal output
stage. SCR line output stages are notorious for occasionally drawing unpredictable and extremely heavy supply
currents during start-up; in fact many
sets that used them were equipped
with mechanical circuit breakers as an
afterthought! The C210 power supply
siliconchip.com.au
This 1975 26-inch Lowboy Thorn 9064 also boasted “twin hi fidelity speakers”
and a quality timber cabinet. As with most sets at the time, it was VHF-only.
was one of the least reliable on the
market; it just couldn’t cope with that
sort of hammering.
To be fair, when the C210 chassis
worked, it was quite a good set but
they were hopelessly unreliable and
easily the worst set on the Australian
market in this regard.
The new “Euro-version” three-SCR
line output stage fared somewhat better but manufacturers very quickly
dropped the technique, out of simple
economics if nothing else! When it
was all said and done, it was simply
cheaper to use a switchmode power
supply and a transistor horizontal
output stage and a damned sight more
reliable!
But then a strange thing happened.
Just when we thought the SCR line
output stage had been relegated to the
industrial bin of history, the Japanese
cottoned onto the idea! After a fairly
uneventful start with quite conventional designs, in 1975 Sharp started
the ball rolling with a truly awful
chassis called the C1831X. These were
smart-looking little sets with state-ofthe art 18-inch 110° inline-gun tubes,
and performed very well. But after a
year or so (presumably as the electrolytics started to dry out), they started
to fall over like flies.
And they were just about unfixable!
It was the same sad story as with many
other SCR designs: you replace everything, and it still blows up at switch
on! Apart from that, they had appalling
chassis access, making them almost
impossible to service in the home.
From memory, I think they were the
only colour sets we wouldn’t accept
under service contract!
But to give them credit, Sharp
quickly realised the error of their ways
and went over to the tried and proven
switchmode power supply/transistor
line output system.
However, just when we thought it
was safe to go back into the workshop,
National (now Panasonic) decided to
have a go, or show Sharp how it was
done, or something!
It was the same story – plagued by
dry joints, blown up by even slightly
tired electrolytics and “spooks” on
Channel 0. Well, the flirtation didn’t
last loo long there either and the SCR
line output stage finally bit the dust!
The C210 was such a disaster that
HMV soon started selling fully imported British-made sets using the “Decca
33” chassis. This had the distinction
of being the only mass-market colour
TV sold in Australia with valves in
it! After their flirtation with “hi-tech”
SCRs, obviously HMV weren’t about
to take any more chances!
Ironically, they were damn good
sets! In a store display, the Decca 33
would always stand out for picture
quality and they were considerably
more reliable than many of their
all-solid-state competitors. This was
April 2005 39
The C2201 was the first Rank Arena set available in Australia, along with the
C2601. They were very successful and “The Bulletin” magazine reported that
Rank Arena had 17% of the colour TV market in 1976.
probably at least partly due to the
fact that they were fitted with power
transformers with a special winding
that provided the exact voltage needed
for the series heater string, rather than
a dodgy dropper resistor.
Their presence in the market also
provided a handy source of valves for
all the “odds and sods” colour TVs
brought in to Australia by European
migrants!
The Thorn 4KA
This chassis was almost as unreliable as the C210 but at least there was
a reasonable possibility of fixing the
4KA and having it keep working long
enough to get it out the door!
I think the 4000 chassis would
have to be a leading contender for the
most over-designed set in television
history! Admittedly, the K9 was a
pretty complex beast but at least they
mostly used common parts and they
didn’t break down all that often. In
fact, while there are quite a few K9s
still working even to this day, I don’t
know of anybody who had a working
4KA past 1990!
The 4KA was the “Ocker-ised” version of the English Thorn 4000 chassis. The UK version had a live chassis
and used a full-wave rectifier (ie, it
was “hot” which ever way round the
40 Silicon Chip
mains Active and Neutral leads were
connected). For Australia, they simply
fitted it with an isolation transformer, a
move which was adopted by a number
of European manufacturers as the easiest way to make their sets meet local
safety standards.
It’s interesting to ponder just what
went through the designers’ heads
when they came up with the 4000.
Like most of the locally-made sets, it
came with a choice of 56cm or 67cm
110° picture tubes but unlike most of
the other manufacturers’ offerings,
these were a special RCA narrow-neck
delta gun tube (which didn’t seem
to work any better than the standard
wide-neck Philips tubes). The matching deflection yoke was also from RCA
and was originally designed for use
with a Thyristor line output stage. That
plus the fact that the 4000 uniquely
had separate horizontal output and
EHT generating transistors strongly
suggests that it was originally meant
to use SCRs in the horizontal deflection section.
The 4000 also had an incredibly
comprehensive set of convergence
controls, all brought out via a monstrous cable to a paperback-book-sized
hand-held control box that could be
unclipped and brought round to the
front of the set. Instead of the usual
conglomeration of variable inductors
and wire-wound pots, the controls
were all thumbwheels similar to those
on a pocket radio. They were clearly
marked with their functions and were
a delight to use when the thing was
working properly which sadly, wasn’t
all that often!
Thorn had developed an unfortunate fixation with thick-film modules,
which still live on today in the form of
the ubiquitous “Sanken” audio amplifier modules.
The notion was fine in theory: a resistor network could be formed onto an
insulating ceramic substrate, trimmed
with a laser, connecting wires, transistors and other components soldered
on, and then the whole assembly
dipped in epoxy. The idea was that
complete circuit modules could be
built this way and the heat-conductive
ceramic substrate would ensure that
all the components were kept at the
same temperature and so avoid thermal drift problems.
There were several of these in the
4000 chassis and they were all hopelessly unreliable. Towards the end of
the 4KA’s production life, AWA-Thorn
started substituting small circuit
boards which were far more reliable
but suffered horrendous thermal drift
problems. The static convergence
would often drift 5mm during warmup!
The 4KA also had tremendous
problems with its chroma decoding
circuitry. This must have started
fairly early in the piece because the
subcarrier oscillator and chroma
processing circuitry were all located
on a small plug-in board and several
different boards were used, none being
particularly reliable.
I think the original idea was to have
an elegant state-of-the-art two-chip
colour processing system: a TBA395
for the chroma processing and subcarrier oscillator and an MC1327 for
the decoder and output, but Thorn just
couldn’t get it to work properly.
The 4KA was so unreliable that, in
1975, following HMV’s lead, AWAThorn started importing British-made
56cm and 67cm sets using the older
Thorn 3500 chassis. Although this
seemed like a huge step backwards
for many, at least these sets with their
antediluvian 90° delta gun tubes and
strange transistor types were reliable
and properly set up, they gave an excellent picture. The Australian version of
siliconchip.com.au
the 3500, (dubbed the 3504) was fitted
with an isolation transformer and a
standard 13-channel VHF tuner.
The above three models were probably the most noteworthy/notorious.
Most of the other brands simply behaved themselves and so there’s not
much to say about them really. That
is, while there were certainly a lot of
these sets sold, they were not, as the
police might put it, “models of interest” to us!
National
National’s (Panasonic) first entry
was a chassis known locally as the
2000 (also “M4”), which appeared in
several screen sizes and models.
This chassis was actually the very
first locally manufactured colour set
I ever saw and I still have a working 56cm sample in my collection!
It seemed the Matsushita designers
didn’t want to miss out on anything,
since this chassis had a mains stepdown transformer, an SCR voltage
regulator and a bipolar transistor as
an electronic filter, which sadly, were
the only unreliable parts of these otherwise excellent sets.
Our first reaction was one of abject
horror when we saw how the chassis
was constructed though, with quite
poor service access!
Pye
For a home-grown effort, the Pye
CT25 was quite well-designed and
relatively trouble free and unlike many
of its “countrymen”, these sets tended
to stay the distance.
Unusually for a “Euro-centric” design, it used a simple mains stepdown
transformer and a Japanese-type series
regulator for its 120V HT rail. Pye
were also unusual in using an inline
gun picture tube from the start; other
manufacturers took a couple of years
to catch up.
Otherwise, there was nothing whatever unusual about its circuitry, which
is probably why so many of them
lasted so long!
Sanyo
Another chassis that was “underrepresented in crime statistics”, the
Sanyo was another fairly conservative
effort, with a simple linear regulator
power supply using two transistors
in parallel.
There are still a few of these in
operation today, although at some
siliconchip.com.au
One of the early Philips colour sets – this was taken from an advert at the time
complete with the then-standard “simulated picture” disclaimer . . . did they
think that viewers would complain if the yacht sail did not poke out of the top
of the television when it was installed in their loungeroom?
point they would be in need of a bulk
electrolytic transplant!
Rank Arena
These sets were basically a locally
assembled version of an NEC chassis.
The story went that a consortium of
local manufacturers was offered the
choice of the British-designed “true”
Rank chassis or a badge-engineered
NEC chassis. Legend has it that they
took one look at the British effort and
took the NEC option!
Although the NEC chassis worked
reasonably well, construction-wise
they were a bit of a mess, the earlier
designs being pretty much an NTSC
chassis with extra circuitry tacked on
for PAL decoding.
They were less reliable than most
of the fully-imported Japanese sets,
but they were cheap and cheerful and
most customers were satisfied with
their purchases.
Their only real vice was that the
insulation around their EHT triplers
often used to fail without warning,
unleashing a noisy fireworks display
that traumatised many a snoozing
household pet (and its owner!)
The Japanese invasion
To give the local manufacturers
a sporting chance, Telefunken, the
owners of the PAL patents, enforced
a 6-month moratorium on the importation of sets with screen sizes 51cm
and under, until the actual commencement of full-time colour broadcasts in
March 1975.
As I said, we had good reason to fear
an onslaught of cheap Japanese-made
sets, in light of our experiences with
their monochrome efforts!
I was working for AWA-Thorn when
the imports began and we were frankly
left open-mouthed when the first
container of 1000 AWA-branded (and
Thorn) 34cm Mitsubishi portables
duly arrived – not with horror but
rather with amazement. Every single
one of them worked!
OK, a couple of them had purity errors that needed a touch of the degaussing wand and one or two of them had
minor static convergence errors, but
compared to what we’d been used to,
this was unbelievable! With the 4KAs,
as each shipment arrived from Sydney,
it had become standard practice to
take them all out of their cartons, sit
them on top, and let them run without
antenna input for about two weeks!
Out of every lot of 100, after the first
day there’d typically be 10-15 blank
screens (some of which responded to
switching off and then on again) and
an equal number of screens with snow
some colour other than white! Each
day, the number of duds was a little bit
April 2005 41
the life of the cathodes, it seems to
have done them a power of good!
Bypass operation
A view inside a Ferguson set (actually a 7C06) of the period – they sure knew
how to fit a lot in in those days! Of course, most of what you see in today’s sets
would be replaced by a couple of large ICs and a few other components.
smaller, until eventually a week could
go by without failures. Of course, then
we’d go round plugging in an antenna,
and the fun would start again!
The story was the same with just
about every Japanese import: for sheer
reliability and price, the Japanese were
simply unbeatable. If I had to make a
choice, I’d say that JVC gave the best
all-round package of appearance, image quality, reliability and value for
money. Apart from a couple of notable
exceptions, you really couldn’t go
wrong!
Actually, “Dad’s TV” is a bit of a
family joke that is a case in point.
My father turned 70 in July 1975 and
so my brother and I decided we’d go
halves in buying him one of the new
“AWA” 34cm portables. I actually paid
the “dealer price” of $333, which in
those days was a ludicrously low price
for a working colour TV set! He was
as pleased as punch and as he was
bedridden a lot of the time. He didn’t
expect to be with us much longer and
so he kept remarking that the little set
would “see him out!”
However he got over that illness
but true to his word, when he finally
passed on 28 years later in September
2003, aged 98, the set was still going,
with the picture tube as good as the day
42 Silicon Chip
we bought it! What’s most remarkable
is that it only ever broke down once in
all that time (after 22 years).
Recently I saw an identical set at
a flea market for the princely sum
of $5 and I bought it for spare parts.
Would you believe that when I got
that set home, I found it was also still
in working order? After a few minor
adjustments, it is also producing as
good a picture as it did the day it was
made – just like the 56cm version of
the same chassis which I found during
a council clean-up 10 years ago and
fixed for a few dollars!
There’s another bit of irony here too.
Many of the first wave of imported
sets had the “instant picture” facility,
where about 4V (“standby”) was applied to the CRT heater while the rest
of the set was off. This heater voltage
was then increased to the normal 6V
when the set was switched on.
Grave concerns were raised as to
the effect this “convenience” feature
might have on the longevity of the
picture tube cathodes, particularly if
the set was to be taken under service
contract.
Well now we know! All of the sets
I’ve seen with tubes still in perfect
condition after 30 years were the ones
with this feature! Far from shortening
One of the weirder aspects of the
Telefunken’s attempts to regulate the
market via their control of the PAL
patents was the “PAL bypass” fiasco.
In 1968, Sony announced the development of their revolutionary Trinitron picture tube. It certainly produced
the best pictures available at the time,
and Sony caused a lot of concern with
their announcement that they would
not be licensing the technology to any
other manufacturer, presumably hoping to corner the market.
However, in retaliation, Telefunken
refused to issue Sony with a license to
manufacture PAL receivers, effectively
locking them out of the lucrative European market. Sony then announced
that they had developed a chroma decoder that didn’t actually infringe on
the PAL patents, because it essentially
turned the PAL signal into NTSC.
The upshot of this was there were
a few fully-imported sub-51cm sets
imported into Australia before March
1975, some by Sony and a few from
Mitsubishi. Because they didn’t actually use PAL decoding, they were
prone to the “green faces” problem
of NTSC, although properly set up,
I doubt that too many people would
have noticed the difference.
However Telefunken insisted that
these decoders did in fact infringe
on the PAL patents, as they relied
on certain characteristics of the PAL
signal to determine which lines held
PAL encoding and which held NTSC
encoding. In the end, Telefunken relented, after experience with the US
NTSC market showed that consumers
weren’t all that impressed with the
Trinitron tube, not if it meant paying
substantially more for the technology!
Apart from that, neither the Sony sets
nor the Trinitron tubes turned out to
be particularly reliable, and even after
the Trinitron patents lapsed, no other
manufacturer seemed interested. It’s
rather sad now after all this time to see
“Badge Engineered” Sony-branded TV
sets with ordinary tubes in them.
One of the minor mysteries of all
this carry-on cropped up when HMV
started selling small Japanese-made
“General” colour sets under the HMV
and Healing brands. There was nothing particularly noteworthy about
these sets except that they used a
siliconchip.com.au
These two Toshiba sets from 1978 show just how far TV
sets progressed in three years. The set at left was a basic
VHF/UHF model, while the unit at right featured an ultrasonic remote control!
“weirdo” two-crystal PAL chroma
decoder system that would almost certainly have successfully sidestepped
the Telefunken patents but they also
used a perfectly standard PAL delay
line system that most emphatically
would not! It seems almost as though
they changed their minds half way
through!
The beginning of the end
The start of unrestricted importation of cheap colour sets pretty much
marked the beginning of the end for
the larger TV service companies.
When colour was first on the horizon,
the local manufacturers began to work
out warranty service deals with the
service companies and prices were
agreed and so on, but this was on the
basis of the original estimates of colour
set prices before the tariff cuts were
announced.
With their prices effectively cut
in half, the manufacturers naturally
wanted to halve the service contract
prices as well – but of course, it doesn’t
work like that. For all practical purposes, the service cost was the labour
cost, which remained stubbornly the
same!
The result was that most of the
manufacturers decided it would be
more cost-effective for them to provide
their own service departments and
that was how I came to be working
for AWA-Thorn. Unfortunately, most
of them badly overestimated the reliability of their own products, and so
their service departments became
hopelessly overloaded. The problems
were massively complicated by the
actions of certain smaller concerns
siliconchip.com.au
who suddenly started offering cut-rate
service contracts to some of the big
retailers, who had no way of knowing
that these outfits hadn’t spent a cent
on staff training or upgrading their
equipment. It was pretty much a case
of “take the money and run”, leaving
the manufacturers (ie, us) to face the
angry customers.
In the current climate of consumer
protection laws for everything, it’s
hard to imagine what it was like back
then. In those days it was perfectly
normal for a customer to spend up
to a thousand dollars on a colour TV
set, have it fail the very first night,
and then have to wait days or weeks
for someone to even come and look
at it! I had to make many a late-night
house call with a 4KA chassis on the
back seat of my car!
Of course, with the wafer-thin profit
margins involved with the new cheap
imports, the importers/manufacturers
were obviously keen to screw an even
lower service contract price out of the
service companies, which was generally greeted with statements like “Yeah,
right!” This was well before anybody
realised how reliable the Japanese sets
actually were. If the service companies had known that, they could have
cleaned up with low-price contracts on
sets that never broke down.
So in the end, the importers realised
that it was probably going to be cheaper to simply keep a supply of spare sets
on hand for replacement purposes or
spare parts, which is pretty much the
practice today.
By the early 1980s, TV set manufacture had pretty well ceased in Australia, although some manufacturers
maintained a “screwdriver industry”
presence, basically assembling some
of their larger models locally from
fully imported components. The arrival of VCRs and things like personal
computers revived the fortunes of the
servicing industry to a certain extent
but slowly it regressed to the “Mom
and Pop” style of independent operators typical of the 1950s.
Much the same thing happened in
New Zealand, incidentally, although
things happened a little differently
there.
What used to be one very large
service organisation with branches in
most of the larger towns, became a sort
of “McDonalds franchise” operation,
with independently owned branches
supplied by a centralised parts buying agency.
It’s hard to know where the future
lies. In this era of $95 34cm portable
TVs, $98 VCRs, $50 DVD players and
$495 2.5GHz PCs, obviously it’s going
to be a lot cheaper to throw things
away than get them fixed.
Nonetheless, as “Serviceman’s Log”
can attest, people are still sometimes
willing to pay an over-the-top price
to get something fixed, purely on the
basis of: “well, I know how to operate
that set!”
Organisations like WES Components do a sterling job of keeping small
servicing companies in business, combining an enormous parts inventory
with fast delivery. It’s truly amazing
what you can still get parts for!
Having said that, my local electronics
repair shop has just closed down for
good and that’s something that’s occurring far too often these days!
SC
April 2005 43
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