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VINTAGE RADIO
By JOHN HILL
The winners of the Hellier Award
As explained in last month’s Vintage Radio
column, the Vintage Radio Club of North East
Victoria Inc has a special annual activity – the
Hellier Award. This year, the award centred
around building a crystal set & there were two
categories involved: open and vintage.
Last month’s Vintage Radio story
was about the crystal set I built for this
year’s Hellier award. I enjoyed making
the set and it had been my intention for
the past six years to make that receiver.
Previously I never found the time; that
is, until the Club’s award activity motivated me sufficiently to get on with
the job and get it done.
As a result, I have built my “Classic
Crystal Set”, I participated in the Club
activity, and now the little receiver
makes an excellent display item. It
is a good “show and tell” attraction
to have when other collectors come
to visit me.
So other vintage radio clubs take
note. A club project centred around a
common theme is good for club morale. In the case of the Hellier award,
interest in what others are doing is
good socially and the collective display on judgement day can be interesting and wide ranging.
The North East Club had 15 crystal
sets entered for the Hellier award,
with about a 50/50 representation in
each category. It took several hours to
demonstrate the receivers and judge
them.
The demonstration consisted of
hooking up each crystal set to the aerial
and earth supplied. The set’s output
was then relayed through a small au-
dio amplifier so that all those present
could hear how well, or not so well,
each set performed.
The judging was done by the club
members themselves. They were
issued with score sheets and points
were allotted as follows:
(1) Open Class – performance 30, design 30, construction 20, cabinet 20.
(2) Vintage Class – performance 20,
design 20, construction 30, cabinet 30.
It would appear from these point
scores that the vintage receivers were
not expected to perform as well as the
open category sets, nor would their
design be as innovative. The vintage
models were given more points for
construction and cabinet.
If that was the assumption then it
proved to be false, because many of
the vintage receivers were amongst
the top performers, with some having
quite elaborate circuits.
The four scoring categories – performance, design, con
struction and
cabinet – were not as straightforward
as they may seem, as each category had
Harvey Utber’s winning
open class entry featured
twin coils, twin tuning
capacitors & a variable
coupling capacitor (top).
This receiver was not only
easy to operate but was a
very good performer too.
Harvey made the comment
that the stations line up
very well to the nonexistent dial pointers!
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many aspects to it. Let’s take a look at
each category in turn.
• Performance: how many stations
could be received, how well the stations were separated, and the strength
and clarity of output.
• Design: ease of adjustment, ability
to operate on different aerial lengths,
originality of design and innovation
(circuit and relevant information to
be supplied).
• Construction: neatness, winding of
coils, accessibility of controls, connections, joints and soldering.
• Cabinet: baseboard, front panel,
finish, style, authenticity, aesthetics
and general appeal (all very subjective
stuff).
This photo shows the control panel of Bob Young’s winning vintage class entry.
Several hours of intense training is required before one gains complete mastery
over the controls.
Performance tests
If we can go back to the performance
aspect of these crystal sets, it is interesting to note that they were being
tested in Benalla, Victoria. In such a
locality, it was found that the better
sets could receive four stations: the
local Radio National, 3NE Wangaratta,
3SR Shepparton and 2CO Corowa.
Not all of the crystal sets could pull
in these four transmissions, with some
of the simpler sets being restricted to
Radio National, which was by far the
strongest signal.
Just to make things difficult, the
aerial that had been erected was approximately 55 metres long. As one
of the design criteria was the ability to
work with different aerials, this extra
long aerial made it more difficult for
sets of simple design.
Those crystal sets that could pull
in all four stations without inter-station interference were indeed well
designed. What’s more, a surprising
number of receivers were capable of
doing just that.
A rear view of Bob’s crystal set. The two coils behind the front panel are wound
with Litz wire, while the loading coil at the end is a slider type. All connecting
wires are of square busbar. The set has been built for display purposes.
The winners
Well the big moment finally arrived.
The scores had been totalled and the
results were read out. In the open
category, Harvey Utber was first, Pat
O’Shannessy second and Marcus
Chick third. In the vintage category,
Bob Young was first, Yours Truly second and Ralph Robertson third.
After the judging, it was time to talk,
look, ask questions and take photographs. Because the crystal sets were
spread over several tables, it was not
possible to photograph them all, nor
would it have been possible to include
all of them here in Vintage Radio. How-
Also entered into the vintage category was this neat set built into a wooden box.
Note that both coils have sliders instead of the more usual taps.
ever, the winners and some of the other
sets are shown in the accompanying
photographs.
It is amazing to think that in this
“high-tech” age, so many grown men
would want to build a crystal set. Yet
October 1994 79
"Scruffy Mk.1” was
entered in jest to prove
just how rough a simple
crystal set can be & still
work. Unfortunately, it
performed dismally on
the extra-long aerial &
came last in the open
section. The “boulder”
mounted between the coil
and tuning capacitor is a
large lump of galena.
many did just that and they all enjoyed
the experience.
It is interesting to note that the
vintage category winner, Bob Young,
is actually in the computer business.
Even so, Bob still likes to tinker around
with old radios and crystal sets in
particular.
Currently Bob is writing a book
about crystal sets and I have had
the privilege of reading some of the
early chapters. I can only say that it
is a brilliant work which should be
eagerly sort after when the book is
complete.
Bob’s writing technique is wonderfully straightforward. He has the ability to make complex issues understandable and his writing style has a touch
of humour about it as well. Whether
one is interested in crystal sets or not,
there’s heaps of good basic information
in the book. I hope to review it when
it is completed.
Well that’s about all there is to report about the Hellier Award and the
activities of the Vintage Radio Club of
North East Victoria Inc. If anyone in
that area wishes to contact the club,
they can write or phone the secretary,
Mr Ian Milne, 48 Smythe St, Benalla
3672. Phone (057) 62 5841.
Germanium diodes
In what space is left, I will continue
with the crystal set theme and relate
what I recently discovered regarding
crystal detectors and germanium
diodes.
As a young lad, I built many crystal
sets and well remember my father
coming home one day with one of
These vintage sets captured the true look of the 1920s. Most
early crystal sets were enclosed in solid timber home-made
cabinets.
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the new “u-beaut” germanium diodes
–the wonder device that would solve
all my crystal detector problems. To
cut a long story short, the new diode
was not as sensitive as the old crystal
detector and reception was noticeably weaker when it was in use. All I
can say is that it was one of the first
of its type and it never lived up to
expectations.
I have since had to reconsider diode
performance and now know that a
modern germanium signal diode is as
good as anything, not to mention the
convenience factor of such a component. But have you ever tested various
diodes with an ohmmeter? I have and
they vary quite a bit.
Their forward resistance is about
the same at around 3kΩ, while the
reverse resistance varies from 0.5-2MΩ
This neat and unusual crystal set uses a form of variometer tuning, whereby one
coil slides over the other. A match box receiver (not shown) also operated on the
same principle.
or more. When used as a detector in
a “crystal” set, they all perform much
the same.
Testing a “Neutron” crystal (a commercially made crystal for crystal sets)
was a bit of a shock. “Good spots”
produced approximately the same 3kΩ
forward resistance as a germanium
diode, while the reverse resistance
amounted to less than 50kΩ, with most
readings about 10-20kΩ.
As mentioned in last month’s story,
alternately switching from this crystal
detector to a germanium diode detector shows no discernible difference
if the crystal detector is properly
adjusted on a good spot. And while
that seems to be contrary to what are
generally accepted “facts”, practical
experimenting proves the point.
Regarding the crystal sets entered
in the previously mentioned Hellier
Award, the open class mainly used signal diodes for detectors, whereas the
vintage class used crystal detectors.
Many of the top performers were in
the vintage category, so the difference
(if any) is negligible.
But a germanium diode sure is conSC
venient to use!
Now here’s a clock radio with a difference! A clock & crystal set complete with
its BSA badge placed this outfit in the unofficial novelty section.
October 1994 81
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