The Carbon County news. [volume] (Red Lodge, Mont.) 1924-1931, 1925-04-23

bout the tuner showed that he had
aimed little lead on the young son
whose superior radio knowledge had
become such source of annoyance
to father. When | reached the Smith
household the big machine was set for
Inc strain of an opera, but down on
the floor Smith and Smith junior were
busy with a few wires and knick-
knacks which they insisted would soon
be receiving set.
"You know" said Smith, divulging
his discoveries, 81 get puzzled when |
try to figure out those wiring dia-
grams but when | actually start to
make set and follow the instructions
it's really very simple. | find | have
an end of a wire here and one there,
and very often common sense tells me
where to attach them"
Fine!" | said. you've got the
right idea. About the best way to dis
cover how your big set works is to
start building small one. Pretty soon
the two meet and you're ready to talk
super-heterodynes as fuently as for
eign exchange"
Smith laughed. you're an opti-
mist" he accused me. I'D think the
world was mine if even had slight
idea as to how the simplest set works.
He said this while Smith junior ran
over to friends house to borrow a
fixed condenser, so Smith could talk
freely.
"For the simplest set, and one that
probably wouldn't work except under
the most favorable conditions, you
need but an aerial, ground connec-
ton, an induetance of some kind, a
crystal detector and pair of ear
phones. Crystal detectors are of sew
eral varieties, some being very cheap
and very pe-Sy, While others that are
scaled higher in price are quite salts
factory. The wise radioist just goes
to the accessory store and buys the
best they have. The inductance, as
told you before, can be merely a coil
of wires that you can tap at any turn
you desire. The telephones are story
in themselves, but for your purpose
just picture them as delicate electro
magnets operating upon a thin dia-
phragm which, in vibrating, gives the
same sound. values that are being
registered on the microphone at the
broadcasting station.
The next thing is to connect these
simple units so that they will form q
circuit, for you know that all electrical
instruments operate only when the cir
cults are complete and correct.
Start with the aerial, for here are
where the radio frequencies are com
ing in. The aerial gathers the faint
energy and conducts it down to th'
lead-in wire to one end Of the Undue
lance device, the tuner. The energ.
is picked up from whatever turn 0.
the inductance coil you tap and is thel
led to the crystal detector and through
~ - +ha c-,o,.u1
"You know that the tuner is used t.
bring the battle-ground circuit int
tune with the radio waves you wan
to catch, but perhaps you forget tina
the frequencies of these waves are 8
high that you couldn't begin to hea
them with the ear-phones. The radi
waves may be alternating or ocillat
ing several hundred times per SECOND
Somthing has to be done to chang
these into frequencies that are With
hearing range.
Here's where the crystal detecto
figures. The phones are connected
series with the detector. BY this
mean that one of the phone wires
attached to the post of the detectC
where the higher frequency is entei
ing while the other is attached to II
most Of the detector that leads to Il
ground connection. The phones, Their
fore, register the audible sounds thi
the detector makes possible.
with such an arrangement, hoS
ever, you wouldn't hear thing unit
the waves you we're catching we
varied at the broadcasting station
someone talking, singing or playir
into the microphone."
Just then Smith junior came ru
ming back with the small article know
as a fixed condenser. Smith and
stopped a moment to watch him co
meet it in series with the phones. TIL
is, he connected it across the circu
Of the phones just as though he we
cutting the phones out altogether.
Now what's that for? Smi
asked.
The boy shook his head and muml
ed something about the Jones lad g
ing better results that way.
What it does" I said, lis to furni
an easy path for the high frequen
to pass through the circuit. Oths