The Indianapolis times. [volume] (Indianapolis [Ind.]) 1922-1965, 1934-10-17

IlOIl Vi l1l6 dll-E1CCIIlC SGG.
Let the development Of the al1-W
standard broadcast alike through
one instrument is but one of the i'm
portant improvements in the new
machines to be displayed in the
city-Wide radio progress exposition.
Some of the more important i'm
provementS which come hand in
hand with the development of the
all-wave set, but which have been
passed on to the standard broadcast
receivers which will be continued in
production in new models, include:
Enhancement of Selectivity of in
dividual sets.
A new fidelity of tOnal quality.
Introduction of automatic volume
control in a perfected form.
Marked progress toward the elm
ination of eXtraneouS noises.
These new major improvements
will be recognized readily by the
scores who are expected to take adj
vantage of the city-wide exposition
to see and examine the sets.
New Thrill for DiaIers
A new thrill awaits these dialers
for the development of the all-wave
instrument prompts the question
"why be limited by the old broadcast
receiver which brings you but mar
row slice of the air?"
Standard broadcast receivers oper-
ate only between 200 and $50 meters,
while the new all-wave sets which
are really a combination of short
and long-wave receivers reach down
as far as twelve and fifteen meters
and operate efficiently through the
regular range of standard broad
cast.
To broaden the range of receptiv-
ity for the instrument that is adapt
able to the living room, radio en-
gineerS had to build high SenSitivity
and high selectivity into the combi-
nations sets, without disturbing the
capacity of the instruments for the
standard broadcast.
Accurate Timing
This they have achieved by the
development of new circuits, I'M
usually fine and accurate tuning
devices. They also had to cope with
the problem of tone control on the
higher frequencieS which come from
distant points and therefore may be
weaker. This they have met by
clever engineering which makes the
notes of the piccolo and the notes
of the bass as clear through the new
radios as any ear would want them.
Still another problem was the re-
duction of eXtraneOuS noises which
the new. highly sensitive re-
ceivers picked up all too readily at
first. Marvellous filters have been
devised to combat this problem.
Aerial kits which enable more ac-
curate tuning and the exclusion Of
this extraneous noise also have been
developed.
Signal Device
One of the chief problems which
the engineers had to cope was that
of tuning for short wave. This they
dealth with through dual speed
knobs, band spreading devices and
newly designed dials. Because of
the nature of short wave radio it
is easy for a dialer to pass COM
pletely by a wanted station without
knowing that his radio has captured
the desired signal.
One manufacturer is featuring
signaling device which, through the
utilization of a distinct sound, sig
mails the fact that the station you
want is being received.
The band spreading device is one
by means of which stations are
carefully separated on the dial as
the radio fan tunes through the
short waves of foreign broadcast.
1t is like the separation and length
ening of inches on rubber ruler, by
pulling on it.
DialS on the new all-wave radios
are in fact four dials in one. They
are of the easily read airplane type
with scales carefully elaborated to
the band in which the station you
want to receive is operating Some
of the new sets distinguish these diff
ferent bands by colors, others by
marking them.
New Term in Radio
Cleverly enough, the same needle,
the same tuning control, and the