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VINTAGE RADIO
By RODNEY CHAMPNESS, VK3UG
Wow – my first vintage radio!
A horrible looking old wooden-cased table
model radio set has just been dropped (almost)
on your front door step. The owner says “I
know you are into collecting old radios and
things and was sure that you would like this
lovely old set that Aunt Martha had for yonks”.
What he really meant was, “I hope
you’ll take this heap of junk off my
hands as it will save me a trip to the
rubbish dump, and you’ll think I’m
a great bloke”.
I wonder how many collectors started in vintage radio in a similar way.
As a raw recruit to the ranks of vintage radio buffs, the next question is
“What do I do with this horrible piece
of junk? All I know about vintage
radio could be written on the back of
a postage stamp!”
The one thing that you don’t have
to do is try and go it alone. There
are several thousand enthusiasts in
Australia and New Zealand who are
quite eager to welcome you into the
fascinating activity of vintage radio.
Where are the other enthusiasts?
On a local basis it is possible to
advertise in local papers or on local
community noticeboards concerning
any vintage radio clubs that may be
around or to find someone who may
be able to help you restore your first
vintage radio acquisition.
Enquiries at local electronics
stores, the local antique dealers and
second-hand dealers may also help
you find like-minded restorers –
probably ones with more experience
than you possess, which is a decided
bonus.
In New Zealand and Australia there
are national vintage radio societies
that cater for enthusiasts and in each
case there is an enormous amount of
information available through them.
Their addresses are:
• Historical Radio Society of Australia Inc, PO Box 2283, Mt Waverley, Vic
3149. They have a quarterly publication entitled “Radio Waves” which
contains lots of useful information.
• New Zealand Vintage Radio Society Inc, c/- G.W. Lindsey, 110 Sylvan
Avenue, Northcote, Auckland 9, NZ
Getting started
This is one of my favourite sets, the AWA 719T Table Set. It is a 6-valve model and covers
seven bands. Sets as good as this one are worth every minute of a sometimes long and painful
restoration!
76 Silicon Chip
Having had this horrible old radio plonked
on your door step,
how do you physically
go about making it into
something that you
could put on display?
The first point to
consider is whether
the set is actually
worth restoration.
If the set is a model
that is considered rare,
valuable or highly
sought after, it may be
well worth restoring,
even if it is in poor
condition.
It may take quite
some time to get parts
or to make them, so
don’t rush the job. If it
is a common low-value set and not in
good condition, it may not be worth
restoring but it can form the start of
a stockpile of useful parts for other
sets. I have a whole shelf of sets that
are not worth restoring which I use
for spares.
If you have not been involved with
restoration of vintage radios before, it
would be a wise move to get an opinion on whether the set is worthwhile
restoring.
As an example, there is no point in
doing a lot of work on a chassis if the
dial glass is broken and there is no
hope of getting another, particularly
if it is a multiband radio.
Fortunately there are some collectors reproducing dial glasses for
a few sets.
Therefore, don’t start cannibalising
the set out if it is in otherwise good
condition but keep it safely stored
until such time as a dial glass can be
obtained.
Swapping one set for another is
another common activity amongst
collectors, if the set you have is not
one you really want.
Having decided that the set is worth
keeping and restoring, there are several stages to the restoration project.
An attractive cabinet is most desirable
and most of the better timber mantel
or console sets look really something
once they have been cleaned, repaired
(if need be) and polished.
If you are into fine woodwork you
will be able to attend to this part with
confidence. If not, a friend who is a
woodworker can guide you, or hopefully a member of one of the clubs.
solvents as you will severely damage
the finish. And make sure that you
don’t leave drops of water on the
cabinet otherwise it will produce a
white stain which is difficult if not
impossible to remove.
The chassis of the radio can be
cleaned by dusting it with a small
paint brush, vacuuming it using a
brush attachment and later, by using
the blowing attachment on the vacuum cleaner.
Be particularly careful when cleaning around the tuning gang as grit and
grime may lodge between the vanes
and in the bearings. In fact, before
you start cleaning the chassis, the
first step should be to close the tuning
gang vanes so that no physical damage
occurs as you dust around the set.
Oh, and it’s probably not a good
idea to blow out the set with compressed air because you may actually
force grit into places you don’t want
it, such as into the tuning gang, into
the threads of coil slugs or perhaps
even into the voice coil gap of the
loudspeaker!
To clean the top of the metal chassis I use a Scotch-Brite scouring pad
soaked in kerosene and by vigorously
scrubbing it, I get most of the muck
off. Later on, a rag soaked in kerosene
will do a good job on the areas that are
just mucky but not corroded.
The kerosene helps to protect a
steel chassis so that it doesn’t rust.
It can be dried off after it is clean.
Later on the chassis can be painted
if need be.
Don’t use steel wool to clean up
a radio chassis. Inevitably you will
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get strands of steel wool lodged in
the circuit where it can cause short
circuits.
Treating the underside
Having cleaned the top of the
chassis, a look underneath will usually reveal that it is relatively clean,
unless it has been stored upside
down or mice have made a nest in it.
Initial cleaning
Even if you have little knowledge of
cabinet work it is possible to clean the
cabinets both inside and out. Plastic
and Bakelite cabinets can be cleaned
with soapy water.
It is necessary to remove all components such as dials, speakers and
speaker cloth out of the cabinets, as
they don’t take kindly to dunking in
water.
Make absolutely sure that any paper labels pasted inside the set don’t
get wet or they will disintegrate.
Wooden cabinets can be cleaned
with a water-dampened cloth, or
perhaps with a kerosene-dampened
cloth to get some of the water insoluble gunk that accumulates off the
cabinet. Do not use turps or other
The rear view of the AWA 719T set. As you can see, it looks exactly the same as
the day it came out of the factory. Sometimes, though, you have to camouflage
new components into old cases when the original isn’t available any more.
April 1999 77
quite OK and can be washed in water
and the print will stay on.
But, I must repeat the caution about
being careful about cleaning the dial
glass; the print may disappear before
your eyes.
I’ve been caught out on this myself
and have a ruined dial glass. I could
have cried and there was no replace(Left and below): I have several
shelves just like these, filled with bits
and pieces of old radios and in some
cases complete radios that aren’t
worth repairing. But they are a very
handy source of old, hard-to-get (and
sometimes impossible-to-get) parts.
Surplus sets and components can also
be swapped or traded for that
particular bit you really need!
Radios that mice have invaded often
have considerable damage – and they
smell. Having cleaned out as much
muck as possible, spray the switch
contacts, valves socket pins, etc, with
one of the contact cleaning aerosol
sprays. While not being ideal for this
task, CRC2-26 and WD40 can do quite
a reasonable job.
Another big caution concerns the
tuning gang. DO NOT spray the tuning
gang with these products. They might
clean them initially but the residue
tends to attract dust and it can be
partially conductive and may even
upset the tuning, due to a change in
the dielectric constant of the gang.
If you really must clean the tuning
gang vanes, gently brush some methylated spirits on the gang and blow
the lot out with your vacuum cleaner,
taking care that the airflow doesn’t
bend or damage the moving vanes.
All control shafts, pulleys and
slides should be lightly oiled to get
them operating smoothly, as over a
period of years they often seize up due
to corrosion and lack of lubrication.
Caution with the dial scale
The dial scale is a very important
part of the set; without it or with one
that’s badly discoloured or otherwise
damaged, the set won’t be worth
much. Note that the actual station
markings don’t mean a lot.
Sure it’s nice to have all those interstate stations marked on the dial
but remember that some of those
stations no longer operate or they
may have shifted in frequency with
the adoption of 9kHz spacing about
78 Silicon Chip
17 years ago.
Even if the dial-scale is intact, it
may need cleaning. The outside can
be quite easily cleaned with a wet
cloth but the reverse side which has
the station call signs screen-printed
on it can only be cleaned with great
care.
In many cases it just isn’t possible
to wash the dirt off as the printing
will come off too.
How do you know if the printing
will be damaged by washing? Answer:
by testing a small part of the print
with water. Let the water stay on it
for a few minutes to see if the print
stays on or comes off.
If it comes off, you may be able to
remove most of the dirt with a small
dry paint brush. Again, don’t brush
too heavily or it may still damage the
printing. In some cases it may not be
possible to clean the printed side of
dial glass at all. However, many are
ment available.
Having cleaned the chassis and
cabinet, and particularly if they were
in good order to start with, you now
have quite a good static display restored set. Some people only go this
far and don’t concern themselves with
actually making the set go.
However, a completely restored
working set is an even more valuable asset. I like observing how well
some of the vintage radios perform;
often they are a lot better than many
transistor radios.
Full restoration
The next step is where many new
restorers make a big mistake. What
they do is to plug the set into power,
whether with batteries or mains, and
turn the set on.
Usually the set you are restoring
has been sitting in some damp, dirty
location for many years. Mice may
Where to buy parts
Surprisingly, parts for later model
valve radios are not all that hard to
obtain but valves for some of the very
early sets made in the 1920s may not
be available at all.
Paper capacitors (condensers) are
no longer available and most restorers will say thank goodness for that,
as they are usually defective. They
are usually replaced with polyester
capacitors which are much smaller
and look quite different.
Some restorers don’t like to see
new style components in sets and
will even bore out the insides of the
old paper capacitors and install the
smaller polyester units inside.
With many old paper capacitors,
particularly those encapsulated with
pitch, this just won’t be possible
though, as they will disintegrate.
Quite often substitute components
will have to be used if the set is to
function properly, as having some
components like interstage audio
transformers and power transformers
rewound is an expensive exercise. In
many cases these substitutes can be
disguised within the case of the orig-
inal component, as in the example of
the paper capacitors.
Any old radio that you come across
can be a source of components either
now or later on, so don’t throw any
old sets out until you’ve been able to
remove all of the useful bits. These
might be the valves, valve sockets,
transformers, radio frequency and
intermediate frequency coils/transformers, switches, cabinets, speakers,
knobs, tagstrips, dial scales, tuning
capacitors and so on.
The following sources will often
prove valuable in your search for
sets to add to your collection and
for spares: garage sales, antique/second-hand dealers and advertisements
in local papers.
The local rubbish tip can be a useful source too if you are allowed to
scavenge.
What are you interested
in restoring?
Having restored your first set, you
may want to continue collecting and
restoring radios of the same general
type.
Or you may find that your particular interest is in another direction.
Some collectors and restorers like
to concentrate on a particular era or
particular types of radio.
For example, some concentrate on
collecting and building crystal sets,
while others may be interested in
high-performance multi-valve, multi-band receivers. Some are interested
in the 1920s era while others are into
transistor radios.
Initially, I grabbed anything that
I could lay my hands on that didn’t
cost me an arm and a leg to obtain.
As my collection grew I became more
selective in what I obtained as I was
starting to run out of room.
Collections vary from just one or
two sets up to over 500 radios, which
I saw in one collection recently. My
collection is rather modest in comparison.
The photographs in this article
are of one of my favourite restored
receivers, plus a number of wrecked
sets not worth restoring. They are
waiting to be cannibalised to finish
off the restoration of other sets.
Good luck with your venture into
vintage radio, I’m sure you will enjoy
the challenge and the end results. Our
radio heritage is a valuable part of our
social and technical history.
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have had made a home in the set and it
was probably put out there in the first
place because it had stopped working.
For all of these reasons it is most
unwise to apply power to any set
which has not been checked out
thoroughly.
In many cases, the set can have very
serious and sometimes dangerous
faults and if power is applied you can
cause serious damage which could be
irreparable. Having come this far, that
would be sad.
If you don’t have any experience,
don’t even think about connecting the
set to the mains power. Instead, enlist
the aid of someone familiar with valve
sets to get the set operating.
Alternatively, you might consider
having the set professionally restored.
Even if it costs quite a few dollars,
in some cases it will be worthwhile.
Almost always I overhaul the electronics of a set before I am prepared
to turn it on, whether it’s mine or one
that I am restoring for someone else.
Don’t forget that this column has
been going since June 1988 so there
is a huge amount on this subject in
the back issues of SILICON CHIP and
I will be going over some of the key
material in future issues.
Truscott’s
ELECTRONIC WORLD Pty Ltd
ACN 069 935 397
30 Lacey St, Croydon, Vic 3136
Ph (03) 9723 3860
Fax (03) 9725 9443
April 1999 79
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