Richmond times-dispatch. [volume] (Richmond, Va.) 1914-current, 1922-06-11
u! Walter Scldcn.

buOSlGc oil general SlustNltS, ! 90
not know O: any more popular cause
of failure 10 receive the stations
now hroadcast!ug than the fact that
40 one seems TO know the real value
Of p good hook-Gp y thoroUsh un-
Outstanding OF the why's and where
!ore'S ot cling vacuum tuhC
ur crystal set should be the rrst
step With every one who expects 20
obtain efficient results with his set.
TIL. FIRST step Is TO know what the
different characters IN the accom-
panyiHE sketches stand for. In "a
dio. as IN mechanical drawing. =
language OF symbols !s used When
IN American or Frerchman or most
any nationality see the diagrams
shown he viii Immediately under
stand what they mean. Tina, Is.
these characters are universally
known.
What Characters Mean.
Take the first sketch. for instance
The little triangle q; the top means
the aerial. the three or more hori-
2onta! lines at tho bottom, the
ground connection. The sp.5a! means
coil. in this case the outer coil or
primary OF loose coupler The 1t
arrow connected with the ground
VIE means that the number o: taps
or turns used Is variable. either by
a knob and contacts or slider"
On the other side is another coil.
This Is the secondary, or inside wind
ing OF the lcose-coupler. The Fac:
that no arrow connects with i shows
that tho number % tai.S is fixed.
The little arrow IN the top w.Se,
pointed into a lIttle block repres MIS-
~ Crysta! detector. The two straight
lines represent fixed condenser. II
it had an arrow through IL. like in
one in figure .. Il would mean tina;
1t is variable. that is. the capacity
for storing electricity can be ad-
justed The two small circles CON
nec;ed by loop, represents a pair
~ phones. This Is one o. the mos;
popular radio circuits using a crys-
tai detector, loose oupler. fixed con-
denser and phones, for beginners
simple Crystal Set.
Figure : represents an even slim
pler crystal deteCtor set using sin
gie CO., ~ tuning coil. as II is called.
'or the wave length adjustments
You Will notice that although only
ono coil Is used there are two cir
cults Don't you see it7 We'll con
sder this. Imagine everything cut
out except the coil. the variable CON
denssr and the aerial and ground.
The circuit will pick uH waves and
osci!laTe" Now say ;ha; the In
j. the wave length capacity is SOC
meters. Turn the condenser Until!
more capacity Is IL the circuit;
This has The eject O. lowering the
wave length. suppose the whole cir
,uit = now tuned 20 $50 meters and
he COZ. 10 500 meters Now bring
the res, or the apparatus hack and
cut out everything in your inas!na
'ion except the coil. You can see
uoth!nS but . coil osclla,i7G a, 800
meters. !; Is really fact ;hat ,he
I'll IS pot os-!.is:iaE a. 800 meters
bg; a. $50 meters. with a greater
,a2acity FOR transferring energy
ihaH = 4; we've At 900 Sow connect
4 the secondary circuit: the coil
wiz &c; IS : secondary and greater
transfer g, ecsrEy Will take place
than Z Two exactly similar coils
,veye Used.
Best Tube Hook-Up.
The ta!-t c!!cG!: is Z vacuum tube
hooI: -u; :; Is perhaps The simplest
and most popular circuit 70 BE- used
for. broadcast reception. The ap-
pa ql.red = extremely simple.
conetrtt1g ~ the tab. and control.
= varicoup.or. variable condenser t25
plato, ana tn" usual phones and
b" battery The small variable con
dens2r is used for tuning. II may
ne supplemented ~ the taps usually
taken ~ the vartcoupier 1.-The sec
ondary az H., varicouplnr IS rser
Tho tCElcr or rcgcuerator 1t is
represented connected directly with
the plate ana tn. phones. The grid
cond Is represented by the Two
parallel lines in the top connection
lending, To the littlc Zis-za eject
called tn. grid
Tho little triangular thing IS the
nlament, connected through the Mia
n.. =, u >
battery, married in the diagram posi-
tive and negative thus o. and },
respectively Be sure and get tho
positive or plus side OF the rs" bat
terry connected 20 the phones We
recommend this circuit for beg In
ners
old Circuit.
DiusraIn 3 is vha, - known a.
The Ultra AUdiou circuit IT employs
loOs-CoupIer and j. rc-enerat!ye
g. i; VIII receive broadcast con.
certs II Is uscd but seldom al tn.
present ;im". although 1t used to b,
very popu..r when hroadcastinE DC.
gar and people ana not nave any
Thing but ioosee"upler- for rceeiv
ing.
TIL rIekler fecd back Circuit, il
shown IT, Figure g. J. works hos
on ions wave lengths. ]. uses VIVA
is known as heueynomO coils. AN,
INC tuning IS done with variable, con
densois shown .r the diagram. Thu
eir1'ii ana Inc noneEeonn coils use
to ~ the rake.
Vow We COME probably the mos
popular circuits % vogue tor broad
cas-. work y emp. SIS "A varIgquY.c
and two Nariumctsrs and permits %
| very fine tuning aud selcetIyliy .
you may TUNE out UNDERESTIMATE. sta
lions easily The varlcpupler is rcu