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VINTAGE RADIO
By RODNEY CHAMPNESS, VK3UG
A collector in the west: Keith Lang
Quite a few vintage radio enthusiasts now have
interesting and extensive collections of old radio
receivers. One such enthusiast is Keith Lang from
Western Australia.
A couple of years ago, during a trip
to Esperance in Western Australia, I
took the opportunity to visit vintage
radio enthusiast Keith Lang. Keith
retired from farming in 1993 at the
age of 69 and wanted an interesting
hobby to fill in some of his spare time.
Having been involved in radio and
electrical activities for most of his life,
he decided that vintage radio would
be a rewarding pastime.
Keith’s interest in radio started in
1934 at the tender age of 10, when he
built his first “wireless” – a crystal set
(doesn’t every collector start with a
crystal set?). The coil was wound on
a cocoa container which consisted of
a cardboard cylinder with metal ends
but it was the earth that was really
unusual. It consisted of an defunct car
radiator buried in the ground, with the
earth lead from the set connected to
it. Water was poured into the radiator
and, because of the many small holes
that leaked water and the large surface
area, it was very effective.
The aerial was the ubiquitous “long
and high” outdoors type, which was
typical of the era. However, like most
youngsters of the era (and grown-ups
too), Keith was reluctant to part with
seven shillings and sixpence for a
“wireless licence” for his crystal set.
Hence the antenna grew at night and
withered during the day.
When WWII came, Keith joined
the army and became involved with
Signals Maintenance and Training,
which meant he gained a good overall
knowledge of radio transmitters and
receivers. Some sets that he recalls
working with were the 11, 108 and
19 sets, all considerably more complex than the average radio receiver
of the day.
After the war, he became a motor
mechanic for a few years, then took
up farming. Many other activities
kept him busy when there was a lull
in farming activities, such as being a
motor mechanic, drilling 250 water
bores and generally, as he put it, being
a “jack of all trades”.
One interesting activity involved
rewinding Dodge car generators so
that they supplied 32V DC for home
lighting or DC voltages for other purposes. I saw one of the rewound armatures and it was most professionally
done. Many small towns in the 20s,
30s and 40s also had small DC power
reticulation systems and Keith had
quite a bit to do with them too.
High-voltage DC sets
This home-made kitset mantel receiver (circa 1946) came in a stylish wooden
case and has been fully restored. It featured inductance (Ferrotune) tuning.
78 Silicon Chip
There were both AC/DC and pure
DC sets in some of the areas in which
Keith lived, as many towns used only
250V DC supply reticulation. In fact,
this was still the case in Esperance
in 1958, when Keith moved there. Of
course, all DC mains supplies have
long since been replaced with 240V
AC mains.
In their time, DC mains supplies
served small towns quite well. In
some cases, the power was only on
for certain periods of the day and
would go off at night “after the flicks
had finished”. The power would then
come on again early in the morning. In
other cases, batteries were used during
periods of light load and/or to supply
energy during heavy load periods.
Keith is quick to point out the care
needed to service the AC/DC and pure
DC radios which ran off the 250V
DC mains. He strongly recommends
that restorers working on AC/DC sets
use an isolating transformer on AC
mains, as one side of the mains may
be connected to the chassis – and it
can easily be active 240V above earth!
This is deadly if you touch the chassis
and an earthed object at the same time.
Most such sets can easily be wired
so that the Neutral is attached to the
chassis, or the neutral busbar (if fitted)
– but always check. Isolation transformers cannot be used on DC mains
or pure DC receivers and servicemen
had to be extremely careful when
servicing such receivers.
(Editorial note: AC/DC sets in
which one side of the mains is directly
connected to chassis are “death traps”.
Do not operate or work on such sets
unless you are very experienced and
understand exactly what you are doing. The same goes for high-voltage
DC sets).
Another stylish receiver in Keith’s collection is this Philips table model.
Restoration
Keith especially enjoys restoring
wooden console cabinets, so that
they look like new. The internals are
treated with equal care – the sets are
often stripped down to a bare chassis
which he then sandblasts using a
special attachment he has for his air
compressor. A lathe is used to turn up
various parts and to wind coils and
power transformers.
A counter attached to the lathe is
used to count the number of turns
when winding a coil or transformer.
Unfortunately, not many vintage radio
collectors have this type of equipment
or the skill to use it.
There is also a good range of hand
tools and test instru
ments in the
workshop. These include digital and
analog multimeters, an oscilloscope
with a component testing facility, a
capacitance meter, a signal generator
and several valve testers. It is always
nice to have an extensive range of test
equipment for fault diagnosis and the
equipment necessary to make replacement parts.
Recently, Keith restored a 1933
Raycophone “Pee Wee” receiver. This
This multiband portable transistor radio included a flip-up lid with a world
map that showed the locations of major shortwave stations.
is a rather rare set and has a circuit
that’s similar to the simple superhets
described in the April 2000 issue.
After restoration, its performance
was initially quite poor and tracking
down this problem took some time.
In the end, it turned out to be an
incorrect resistor value in the cathode
of the converter stage. Replacing this
with the correct value resistor cured
April 2001 79
Keith’s collection includes a good range of early transistor radios, including a
compact “purse” receiver (next to the matchbox).
the problem and the set now performs
quite well.
Keith’s extensive vintage radio collection, like so many others, has grown
like “topsy” and very few of the sets
are displayed at their best – although
two lovingly restored consoles reside
in the lounge. One of these, shown in
one of the photos, is a 1935 AWA Bandmaster 365B battery console using a 34,
1A6, 34, 30, 32 and a 33 valve line-up.
The set is powered from the 240V AC
mains via one of Keith’s home-made
battery eliminators.
None of the many battery valve sets
in the collection has been converted
to direct mains operation. Instead, a
separate mains-operated DC supply
has been built for each set. Conversely, all the transistor portables
in the collection run on batteries as
it is easier to operate them this way
and saves dragging an AC lead along
with the set.
One of the photographs shows an
HMV 601 “portable” set (AORSM
Vol. 4 Page 147) which can operate
from four sources of power – inter-
A close-up view of the Ferrotune inductance tuning module (at left), as used in
the home-made receiver.
80 Silicon Chip
nal batteries, external batteries, an
external AC power supply and, most
interestingly of all, a 2V vibrator pack.
Yes, that is right, a 2V vibrator pack!
A considerable portion of Keith’s
collection consists of portable radios,
both valved and transistorised. The
valved portables include the following brands: Philips, Astor, Healing,
STC, AWA, HMV, Kriesler, Ferris and
an English “Dynatron”.
The smallest is a “purse” radio
which is smaller than a pack of cigarettes and is seen in a collection of
personal portables in one of the photographs. It boasts five transistors and
is powered by a single AA cell, since
there was no room for anything bigger.
The most elaborate Australian-made transistor sets are three AWA
units. These receivers appear to be
identical until a close inspection is
made. Two are broadcast band sets
with an RF stage but different dial
scales, while the third is a 4-band unit
which tunes from 550kHz to 30MHz.
Quite a number of small Japanese sets
are also tucked away on a shelf.
Car radios also feature strongly and
include examples from AWA, Ferris,
Philips, National and Astor. The intriguing ones are the Ferris M104 and
M106 models, which can be powered
from various sources.
Another unusual item is a homemade set using the Kingsley Ferrotune
front end kit, produced around 1946
(see photo). A few manufacturers
produced inductance tuned radios for
household use, such as Radio Corpo-
ration, Philips and AWA.
There are also a few black and
white TV sets in the shed waiting for
restoration but there are many more
radios in the queue ahead of them.
I asked if there were many collectors around the Esperance area and he
replied that he knew of only one. This
means that there is very little competition when it comes to obtaining sets at
reasonable prices. On the downside,
there is virtually no-one to share experiences or discuss problems with.
Keith has obtained his radios from
quite some distance in some instances
– eg, Albury (NSW) and Peterborough
(SA). Closer to home, sets have come
from Kalgoorlie and Boulder. Garage
sales are a good source of receivers
and generally keeping your eye out
for them and letting people know of
your interest will pay dividends. He
has no particular favourite set or style,
except that they should be wooden
cabinet radios from the mid 1930s
to early 1940s and Australian made.
Keith’s collection reflects a slightly different emphasis compared to
the average eastern states collector.
Some of the sets were different due
to local conditions, as was some of
the equipment used.
But basically we’re all interested
much in the same thing – the retention of our technical history and the
restoration of old receivers. It would
be interesting to swap experiences
with a vintage radio buff from across
SC
the Tasman!
Keith’s pride and joy is this 1935 AWA Bandmaster 365B battery operated set.
These three AWA transistor portables include
two broadcast band only units, while the
third also covers three shortwave bands.
April 2001 81
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