New-York tribune., 1922-07-30

Question .fIl N. ffh 10Y NNt -..-s
r,rce III = radio tfion Can you Ies..
~ ..,,,. lfs-snrr rIfh voice iransniif.lo.
.s vHh code trausni'sion lt nni ~.
40 ffor com fou fnd IN, l,trr
fsfrth uf = receiving s~ff boft felf,.h
..f fr,r.,rs rs power hY Eefting ~ Naf-
isurths as near sr possible -
frouf th~ transmitting flailNn ~ 49,.
fh. 90 nf the tarinmrifr anl h'l 7. "a
meters fh~ frnEih ~ the wave. moFl -.
for hfns dcarfinE purroffa nuln -.
~ fA0-mfi.r Maf'. s...-.,Ir. the
i0f vstsf How rsn you Nfl.I" a
-,.veirrrtn thaf sou aro coins 2" N'
900 ,o1 urr fn fhr Fsmr station .hI'' ="
MOI. different watr lens De p.
Ansv.r-i. The range Of o. radio sta
lion denends upon the amount oi power
n ure- for transmission. lhcro are
s.veral other features which enter INTO
the situation. which cannot be GOV
crned bv any mathematical formula.
This !. due 10 local topography ana
,.,riopr other causes Wireless telc-
,bonv win not travel as far as wire
iess telecraphv with the same amount
IN mower. The reason FOR this Is oe-
cause wireless tclcgraphy deals win
signals of g. constant amplitude. "hiie
wireless telephony deals with ihe
rodulatcd output. the modulationl bc-
inc controlled by the voice. and con
,o5reotly. the amplitude Is equal onif
,o the aversro amplitude o. the vary
ing Infection of the voice.
2. The natural wave length of 70,
ceivine stt can only be- determinea
atitfaetoriiy b. the use OF wave
meter The receiving set increase Us
.ensitivity by getting into exact res
onance with the wayclength OF th'
ffansmittlng station. This also means
that you are getting the maximum o.
fci.ncv out Of the amount or energ,
that BE- picked up by your aerial 4
ysriomctcr ia = clever device for tuning
the iUductancc Of q circuit without
INV irductive losses due 20 dead ends'
or unused turns 4 loading coil i'
us,d FOR the purpose 81 Increasing tne
wave length range Of a receiving or
trsrsmitting station. Il does not m
crease the distance over which Ng-
malls can be- transmitted or received.
but merely adds 20 the warelengin
tuning range.
g The broadcasting stations operate
on $50 meters because they are COM
PEELED TO do so by the povernment'
which issues tao licenses 20 them. TIE
government. however. has not cot su-
preme control over this situation. a. u
r. again controlled hy the lniernationaai
Radio Telegraph Convention. ms
convention determines just what wave
lengths shall be used FOR various pur-
noses In wireless communication. wnicn
OF course includes radio telephony. The
iO.OOO-meter wave. the .00O-meter
wave. tae iO0-meter wave. the single
meter wave or the 50.000-mcter wave
could on be used for radio telephony.
The determination OF a wayclengLh rs
governed by we'll defined facts. and is
purely an engineering proposition. Inc
uayelcngih that station wlil emit
or receive depends upon tie amount
OF inductancc and capacity in the o.
ciliating Tor wireless circuits. These
can be- designed with the greatest Do.
gree Of accuracy and can be confirmed
later =. wsve meter tests. A transmit
ing station can send ou' several wave
lengths simultaneously without inter
ference from the same aerial b. using
what Is Known a. the multiple tuned
srfcnna This BE- somewhat eomp'i-
Gated situation from the transmitting
and ~ tho field