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Restoring a
Vintage Televisi
With Australia celebrating 50 years of television last year, I thought
I should celebrate the occasion and restore a TV set that was around
not long after it started. But like the hare in Mrs Beaton’s cookbook,
I first had to catch my set . . .
I
n my quest to find a television to
restore, I had a particular one in
mind – an AWA Model 229, from
around 1958. My grandparents had
owned one back then; in fact it was
their very first television. They were
the second house in the street to have
a TV set and early on they had made
many new friends thanks to that television!
Back then television was still magic
and somewhat of a mystery to most
people. Crowds used to gather on
the footpaths outside retailers just to
watch the TV sets in the window (often
with no sound!).
I had an old black and white picture
of the AWA, so knew what to look for.
When one turned up on eBay, I just had
to have it. One problem: I’m in Sydney
and it was in Melbourne. So having
won the auction, I arranged to have it
freighted to Sydney. This cost nearly
three times as much as the set.
What have I done?
The set duly arrived about a week
later. It was as described on eBay and
bearing that in mind, I knew it would
take a fair amount of work before this
would be a working clean example of
a 1950s television.
The set, while all there, was dirty.
The set had apparently been stored
in a damp location as much of the
20 Silicon Chip
This old, grainy photograph was the picture that started it all. I wanted one of
these AWA Model 229s, just like my grandparents had back in 1958
siliconchip.com.au
ion
By Timothy Stuart
veneer on one side had lifted; some
corrosion on the chassis was evident
and other components had suffered,
which I’ll mention later. And not
least were the many bugs that over
the last few decades had taken their
last breath between the screen and the
safety glass.
Before starting any type of repair I
like to clean the dust off the chassis,
remove all the valves and check for
anything that’s obviously missing.
Having removed the chassis from
the cabinet and then getting rid of
the dust using some paint brushes,
a vacuum cleaner and a damp cloth,
I then washed all the valves, being
careful not to rub off the delicate valve
number markings.
One valve in the tuner (a 6U8) was
obviously gassy (a white/grey look
inside) and was replaced with a new
one. I next turned my attention to its
underside.
Lots of paper and wax
With all vintage televisions and
radios that I restore, I tend to favour a
complete replacement of the paper and
electrolytic capacitors. While there
is some argument from the purists
about doing this (polyester capacitors
weren’t invented in the 1950s!), I find
I end up with a much more reliable
set and hopefully one I won’t have to
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This is how it arrived from Melbourne after the successful eBay bid. It looks
to be in pretty good condition but notice the peeling veneer (lower right). And
there was a fair bit of damage inside. This photo doesn’t do justice to the legion
of dead bugs between the screen and safety glass!
repair again for a long time.
I use tubular metallised polyester
capacitors for the paper replacements which, while smaller than the
originals, don’t look too out of place
under the chassis, as compared to
the more common ‘orange drop’ type
capacitors.
Following the paper caps, I replace
all the electrolytics. Most high voltage
electrolytics in vintage TVs are of the
chassis-mount (can) type. I leave these
in place on the chassis but disconnect
them. This means there are no holes in
the chassis, where there would have
been had I removed them.
Modern electrolytics are very much
smaller and can be easily wired in
under the chassis, often using the
terminals on the old capacitors as tie
points.
Some restorers go to the trouble
of removing the “innards” of the old
can electros and mount a modern one
inside the can. But not me!
Spending a few hours replacing
these components is very worthwhile and often a TV will be brought
back to life just by replacing all the
capacitors.
Resistance is futile!
Following the capacitor replacement, I then turn my attention to
the higher value resistors in the set.
Experience has shown that replacing
all resistors 100kW and over will also
greatly enhance the chances of the
December 2007 21
television working as it should when
first switched on.
Many old resistors over this value
‘go high’ with age and cause strange
effects on the picture and ineffective
contrast, brightness, volume controls.
Moreover, old high value resistors
tend to go even higher in value as they
warm up, causing all the settings to
drift as the set warms up.
In undertaking the resistor replacement, I found a number to be burned
out, no doubt due to increased current
flow caused by the old paper capacitors being ‘leaky’.
Check those fuses!
Another thing I always do is check
that the correct fuse values are fitted. Many times I’ve found they’ve
been replaced by a nail, paperclip or
something like a 15A fuse where it
should be a 1A.
Next comes the “smoke test” – powering up the old set for what could be
the first time in decades.
Use a variac
To power a set up for the first time,
I always use a variac. This allows me
to detect anything wrong before it fails
catastrophically and causes damage to
other components.
I always power a set up in four
stages. The first stage is with no valves
installed, which checks that the power
transformer is OK and that all secondary voltages are present and correct.
The second stage is to gradually
increase the input voltage to 240V. In
the case of the old AWA, having run
the set for an hour the transformer
was warm but showing no signs of
distress.
Note also that old television sets
usually had transformers with many
input (primary) voltage taps. To increase the tube brightness, unscrupulous servicemen would often change
the tap from 240V to 220V, increasing
the secondary voltages in turn to levels
far above the design voltage. So this
is another thing to check before you
power up the set.
Valves go back in
Stage 3: having passed the transformer test, it was time to plug in the
valves. Initially, I start with just the
rectifier valve(s). Slowly powering up
the set again revealed nothing smoking
or otherwise in distress. Measuring the
rectified high tension (HT) voltages
22 Silicon Chip
I was lucky: I had a complete service manual and circuit diagram to help me.
indicated that all appeared well.
Next check is with all valves installed with the exception of the high
voltage rectifier, damper diode and
horizontal output valve. Again, the
set passed this test. Finally, with the
remainder of the valves installed, the
chassis returned to the cabinet and the
picture tube and speakers connected,
powering up yet again, resulted in a
more or less completely working set.
It works!
With an antenna connected, I could
now see a picture on the screen and
had audio as well. However, there
were a few problems still to resolve.
The picture needed alignment, the
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in vintage televisions is usually relatively simple and I quite easily located
the problem in a low value HT feed
resistor. Replacing it with a new one
completely removed the crackle from
the audio.
After having done the picture alignment and centring, it was time to
watch television, 1950s style.
The pretty parts
While I had been busy working on
the electronics, a friend had been busy
with the cabinet. It was in generally
good condition, so I felt there was
no need to do a full restoration. The
veneer was re-glued and the interior
of the cabinet vacuumed, brushed and
wiped with a damp cloth.
An oiling inside and out makes the
timber look like new and moisturises
the dry wood at the same time.
The cleaned-up cabinet, although
not brand new looking by any means,
is very presentable and is still very
original.
Polishing and cleaning
The accumulation of several decades of dust. The first step in restoring any
old TV set is to get it as clean as possible without doing any (further?) damage.
Contrast this photo with the cleaned (and restored) version overleaf.
While the picture tube was out, the
tube and safety glass were thoroughly
cleaned and many expired bugs removed.
The screen mask was also carefully
cleaned. In this set it was made of plastic so had to be treated very carefully.
The difference this made to the look of
the front of the set was amazing. It was
starting to look nearly new again!
vertical hold and volume pots were
very noisy, there was a noisy crackle
in the audio and one of the speakers
wasn’t working. I put most of these
faults down to the television having
been stored in a damp environment.
Fortunately I had an almost direct
replacement in stock for the faulty
speaker, so I attached the speaker
transformer to the new one and it fitted nicely into the original mounting
holes and speaker opening.
The vertical hold pot was replaced
but the volume put was a different
matter. Being a dual gang, concentric,
switched type, replacements are almost impossible to find these days and
so removal, taking apart and cleaning
is the only option. So far this seems to
have been very successful.
Snap, crackle, pop!
The last problem to fix was the loud
crackle in the audio. The audio circuit
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Some may argue the modern polyester capacitors (yellow) look out of place in a
vintage set but you simply cannot trust the original paper capacitors. I make it
a rule to replace them and high voltage electros and it has paid off every time.
December 2007 23
Inside and outside the restored AWA. Above is the fully
cleaned out and repaired (where necessary) chassis – though
I was quite lucky with the relatively small amount of work
necessary. You can’t see the repaired veneer in the photo at
right but looks every bit as good as the rest of the set.
The final touches
The final touches included cleaning
all the front panel control knobs, the
aluminium front panel and finding
some suitable replacement screws and
bolts to hold the chassis in properly
and the back cover on.
What’s on the box?
Finally it was all back together and
I could settle back to watch TV 1950s
style. This must have been a cosy
family experience back then. With its
small 17” screen, one has to sit relatively close for comfortable viewing.
Still, maybe that’s not such a bad
thing. Bring back 1958 I say!
The end (or is it the
beginning?)
To conclude, although this restoration took place over a number of weeks
and was somewhat time intensive, I’m
very pleased with the final result.
I should also point out that I had
access to a service manual and circuit
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diagram for this set, which made the
restoration a lot easier.
Lastly, although I’ve heard many
stories about hard-to-find parts like
line output transformers for vintage
televisions I must have been lucky.
Of all the televisions I’ve restored
I’m yet to come across any with faulty
transformers or picture tubes.
That has been very good for me, as
restoring a set with such faulty parts
would require another one to scavenge
parts from.
SC
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