Belt Valley times. [volume], January 14, 1926, Page Page Seven, Image 7

About Belt Valley times. [volume] (Armington, Mont.) 1894-1977

Image provided by: Montana Historical Society; Helena, MT

                
-
Tr*nsSat*ter
* 6_4
i«r
t
V
Ov*f* r
£
f
W
I
o
r
4 k
if
sk asv
• The Wiring Diagram of the Amplifier Herein Oeecribed.
By SIDNEY E. FINI'EUSTEIN,
In New York Herald-Tribune.
The honors in audio-frequency am
plification seem to be divided more of
lew evenly between the transformer
end the resistance coupling methods.
Bach system has Its stanch adherents,
who are ever ready to fling masses of
facts, figures and fancies Into each
others' faces whenever a dlscuaalon
of relative merits arises. The trans
former supporters are Just as firm In
tbety belief of the superiority of their
Instruments as the resistance hench
men are in their views on the advan
tages of their devices. '
The writer has used both transform
ers and resistances In the construc
tion of a large number of seta and
after studying the general results ob
tained from them has come to the
nentral conclusion that both systems
are good, but that they are even bet
ter If they are combined. In the Jour
nalistic fashion, to the retalnment of
of each.
The advantage of the greater am
plification per stage afforded by the
transformer, combined with the flaw
less reproduction but lower amplifica
tion of the reslstancea makes the
Ideal combination in the majority of
seta
A complete amplifier of this ad
vantageous type can be made at home
at surprisingly little trouble and ex
pense, and once on hand It finds ap
plication to receiving circuits of ail
kinds. It may be built permanently
Into a set or it can be left available
as a separate unit for connection to
experimental tuners. For the last
purpose it Is especially convenient,
as It saves the constructor of a new
set the worry of providing suitable
amplification to follow the detector
tube.
Pacta Required.
An amplifier such as the one shown
In the Illustration will require the
following parts, which enn be pur
chased at any radio store: Hard rub
ber or composition baseboard 12 Inches
long, 4* Inches wide and hi. Inch
thick ; one heavy audio transformer
not above 3*4 to 1 ratio, three stand
ard tube sockets, two resistance cou
pling units with two 100,000, one 500,
000 and one 250.000 ohm resistors ; one
.0005 mfd. fixed condenser, eight bind
ing posts and the usual busbar and
mounting screws,
definite
A
assembly
procedure
should be followed. First -the general
location of the Instruments should
be determined and all the necessary
screw holes made In the panel before
anything Is fastened down perma
nently.
The devices should be pushed
closely together (there Is no danger
from Interstage bowling, as there is
only one transformer), so as to allow
room on the right and left hand short
edges for Input and output binding
posts.
The wiring will give no trouble.
Aa a »tart the "P" and "B" posts of
tbe amplifying transformer should
be connected directly to tbe two bind
ing poets on the extreme left, which
are designated aa the "Input" ter
minals The .0005 mfd fixed con
denser is also placed across the wires
and can be hidden comfortably out
of way beneath the bottom of the
baseboard.
Of course small holes
will have to be drilled In tbe com
position to past the wires wherever
necessary- .
The Filament Posta
Next the filament posts of the three
sockets, which are all marked "F."
are wired as shown In the -diagram,
and« lead finally to the A battery
* binding posta These should be the
left hand two of the row of four
along tbe long edge of tbe baseboard.
With this much done tbe secondary
of tbs transformer can now be wired
to tbe grid and filament posts of tbe
first tube socket Pro g re ss ing across,
the condenser and resistor terminals
ora wired In the manner Indicated In
tbe accompanying hook-up. With- the
rratotor units that were employed In
this particular amplifier the protrud
ing soldered tabs of the spring mount
ings make the placement of tbe wires
a abort and simple task.
Tbe two poets on tbe extreme right
are tbe output To one le run a wire
from tbe P terminal of tbe last
socket end to tbe other a wire from
tbe B plus post, which is Immediately
adjacent Tbe A plus and B minus
' peat*. If win be noted, are Joined to
gether.
All tbe wiring should be done with
standard round or square tinned bus
bar. Tbe wire need be Insulated with
cambric tubing only In plares where
two wires unavoidably pass each
Tbe
consacrions to the transformer, the
sockets and tbs binding poets.
which are all equipped with strong
screw binding posts, need not be
soldered, but those to the fixed con
densers and the resistor mountings
must be.
The B battery should be of 135
volts, which Is the standard require
ment for resistance amplifiers. With
this voltage the 100.000 ohm resistors
should be employed In the plate cir
cuits of the first two tubes, while the
500, TO ohm leak goes between the
first and second bulbs and the 250.000
ohm resistance between the second
and third In the grid leak positions.
This Is clearly shown In the wiring
diagram.
T wo Variocouplcrt Make
Circuit Very Selective
While a regenerative circuit may be
readily obtained by inserting a variom
eter in the plate circuit R 1* not 80
obtain tickler feed
back with ordinary apparatus on the
market nnlesd honeycomb colls are
used. There are. of course, couplers
with fixed tickler windings. With or
dinary apparatus, however, the double
coupler feed-back circuit Is easily ar
ranged, the objections to single-circuit
action are overcome, and there Is com
plete tuning In every circuit and any
desired degree of coupling between
them.
As commonly employed, the primary
switches of one coupler are connected
to the antenna and ground as osual.
LU
±~ûi
§ S'
8
■
Scheme That Qfvee Fine Control of
Amount of Inductance.
The secondary of this couplet, how
ever, Is connected to the ends of the
primary winding of the second cou
pler, Tbe switch points of the second
coupler go to grid and filament like
the usual secondary connections. The
secondary terminals of the second cou
pler are connected to the pltfte cir
cuit.
The ware-length of the primary cir
cuit Is adjusted by the switch points
on the first coupler, aided by the con
denser in the ground circuit
variable condenser should hove a ca
pacity of .0006 mfd. (23 plates). Tbs
coupling between tbe primary and
secondary is adjusted by rotating the
rotor of tbe first vsrlocoupler. The
secondary circuit Is tuned by the
switch points on the second coupler
and the coupling between the sec- '
ondary circuit and the plate etrcnlt
tickler Is adjusted by the rotor of this
coupler. The secondary of the second
coupler acts as the plate tickled coll.
Thla
tive and give a little better than the
average set's results.—Radio Newa
CHECK SQUEALING
Stop squealing lu the radio
frequency set by:
L Moving the coil closer to
the end plates of the variable
condenser.
2. Cutting down the number
of turns on the coil primary.
8. Adjusting the grid bias
with a potentiometer.
4. Inserting a critical resist
ance, snefa as a rhéostat. In
series with the grid of the radio
frequency tube.
Allow Space Between
Units When Building
When building e set a safe rule to
follow Is to keep each piece of ap
paratus at least two Inches or more
away from other nnlta Tbe biggest
mistakes often made In tbe construc
tion of home-built receivers are try
ing to cramp tbe Instruments in small
quarters and tbe use of metal fixtures
for the mounting. Cotla and other In
ductances In tbe radio-frequency cir
cuit should be placed as far to the
rear and away from other pieces of
apparatus as poaalbto.
Winding of Coils
To specs wires cm coll* the correct
distance, start the cofl with thread aad
wire, at tbe same time applying coo
Mderably more tension to tbe wire than
when no thread Is
After tbe
coll la wound and tbs sod of tbs wire
fastened, the thread may be unwound.
Have Antenna of
Very Few Losses
How to Construct Insulator
That Will Be an Aid in
Sharp Tuning.
In this dayoand age of low loss re
ceivers and high selectivity, writes s
correspondent In Radio News, it Iq
necessary to have an antenna of very
few I oases, or the resistance of the
antenna will be so high sa to make It
Impossible to tune the set sharply
How to do this? The antenna must
be constructed of wire that will not
corrode readily, enameled wire being
the best However, the most Im
portant thing Is to have the beet In
sulation possible. The very beat In
sulator for the antenna la air, but of
course that la out of the question.
Urn of the Plata
Doubtless, someone will think that
because this Insulator was designed for
a transmitting antenna that it Will not
be good for the average broadcasting
antenna. It la only necessary to re
move the aluminum plate at the end of
the insulator and yon will have one of
the very best insulators for a one-wire
W
A
»am eso wuHcas
CL*» Tuet
COTTON 5 O*Kt 0 W
SASA/riN ■.
TIN
SlATt
Pisplata and Qiaos Toothbrush Holder
Used for Insulator.
antenna. The plate Is for use only
when the insulator Is used on a cage
antenna with a transmitter.
The material that la necessary la as
follows :
Long type toothbrush holder with
sorewcap at each end. This can be
bought for about twenty cents.
If the Insulator Is for transmitting
antenna use a small aluminum plate.
The other materials are odds and ends
and can be found around the work
shop.
Using Melted Paraffin.
Begin by moving the caps at the
ends of the holder. Stuff small pieces
of cotton In each end of the tube. Now
It will be possible to pour In melted
paraffin. Just enough should be poured
In to seal the tube. This will prevent
moisture from entering the tube and
tbns destroying the Insulating power of
the glass. Instead of paraffin, sealing
wax, such as found on the top of dry
cells, may be used to seal the ends of
the Insulator. Now eyehooks of about
tbe same design as shown In the sketch
and threaded on the end, should be
constructed. When the eyehook is at
tached to the cap it will be found nec
essary to place a big washer on the
Inside of the cap and a smaller one on
the ootalde of the cap. This will pre
vent the ventilation holes on the cap
from pulling out It Is a simple mat
ter to place the alumlnnm plate at the
end of the Insulator. When the plate
Is used It should always be pot at the
end of the Insulator which Is hooked
to the antenna.
When It la constructed, you will
have a very fine Insulator, which takes
very little time to build, has a remark
able pulling strength and Is very cheap.
S. L F. Condensers Aid
Tuning of Wave Meter«
The wave meter, whether It be
plain or be made with all the finer
Improvements,. Is one of the most
handy pieces of apparatus any build
er of receiving sets can have. Here
tofore, tbe tuning of a wave meter
bos been a rather difficult feat be
cause a very slight change In capacity
threw the circuit oat of resonance
The Insertion of a straight-line fre
quency condenser In tbaxbgre-meter
circuit will greatly facilitate the find
ing of the resonant point because a
large change lo dial setting Is essen
tial for a small change lo capacity,
except at one end of tbe dial, but as
the frequency variation is the same,
tuning may be accomplished with the
same ease.
For wave-meter construction It Is
essential that condensers with heavy
plates, strong supporting members
and accurate spacing be used. This
necessities the use of sn instrument
with concentric plate* because eccen
tric plate condensers ore of a neces
sity made with thin plates, which
makes the capacity calibration sub
ject to change without notice.
How to Enlarge Holes
When Building Receiver
The best way to make boles in a
panel large enough to take the Jacks
or for tbe shafts of variable condens
era, rheostats or other Instrumenta
fal to first drill a large bole and then
replace the drill with a flat file of
rather fine groin. A fiat file will
usually taper down to sufficient width
to Just about sqoeese into tbe hole
made by the drill and If it is turned
in the brace slowly, usually in a re
verse direction, the file will cut away
the aide of tbe tarte, gradually enlarg
ing It until It hi of sufficient size to
accommodate the Jack. Do not try to
work tbe drill feat or It may nap off
tbe fila If It seems to stick and work
itself Into a self-cut thread, reversa
tbe direction end work at a slower
rate. This method of enlarging boles
will greatly assist In building tbs re
cslvsr and at tbe
tints will give
Slants on Life
By J A. WALDRON
77
A Superficial Conclusion
nn HB servants of the Melfords were
trained to a silence more subtnls
slve than usual, though tike other
servants they let their tongues wag
below stairs. Those of them that bad
to do with breakfast# especially
might have passed with the dumb, for
at breakfast Melford was Irascible If
speech happened to Interrupt hla
analyses of the financial pages, gven
Mrs. Melford, who made It a point to
come down to breakfast with Melford,
was usually a silent partner at that
function. This rooming, dressed With
core, as always, she was so aBurtng
that no man but Melford could have
perused financial pages while he might
have scanned her. She waa ten year*
younger than her husband.
"Do yon remember about the DellaT"
she asked.
■ He was negotiating his coffee, end
apparently dissatisfied with Its beat
"The Dells? What about them!"
"You promised me you would g®' to
the affair tonight"
"What affair?"
"Why, they entertain,
have engaged several notable artists
to assist."
"Dell has nothing elm to da
bava Pm too busy."
"But you promised me. And yon
never go out with me nowadays"
"I give yon full liberty to amuse
yourself, don't IT And plenty of
money and all that I have two or
three deals on that take all my time.
I'm about the first man downtown In
the morning, and you find me at work
Id the library when you come In at
night I don't even go to my clubs."
"But Isn't It your place* to go with
roe once In a while—at least for ap
And they
I
pearance' sake, even If you find no
pleasure In my companyT"
"Nonsense I I'm known aa a busy
man. One of them days, when I've
carried through the plana I'm work
ing out, HI try to be what they call *a
model husband.' Thon TU go with you
as much aa you like."
"Would you, really? I fear the
habita you are forming will never be
broken."
"But you're having a good time, any
way. You go to this and that con
stantly. Yon have e box at the op
"Thsrs Go«» a Man Hard Hit," Bald
One.
era, the theaters are open to yon, with
dances and what not to fill In during
the season. And yon play tennis and
golf and go shout in the summer."'
"Yes. 1 have to do these things for
Mental relief—and to forget I tack
your company."
"Yet you must meet persons—as
other women do—who are natural
cavaliers—men who have nothing else
to do. I like you to enjoy yourself'—
be looked up to see a strange expres
sion on her face—"and you must per
mit me to go my way."
"But people talk when they aee me
About so much without you."
"People talk about everything that
doesn't concern them. Where's young
Bloomer? Yon used to have him. to
dinner quite often, and be noed to
sqnlre you about. Why can't be still?"
Mrs. Melford turned white and rosa.
"I haven't seen him for weeka" she
ventured.
"Well, look him up. and please let
me attend to my business." And Mel
ford. who bad wasted valuable time,
hurried out to bis motor and was
away.
A month afterward Melford entered
a Wall street buffet earl y one after
noon In an abstracted state. He rec
ognised no one. Two brokers who saw
him pass In the entry abandoned the
■object they had been discussing.
"There goes s roan bard hit," said
one. "You've noted that bis -pet stock.
Orient Mining, slumped this morn
ing?"
"Almost to sera," said the other.
"Have yon been caught In any of
his misadventures?"
"No. I hsd a bunch. I gueaa No
other reason."
-He'» rarely losing his grip. That'»
whst a woman can do even when she's
ont of the market."
"Yea Women are to blame for a
lot, even when they seem to be by
stander«. Isn't It strange Melford
didn't ee* his wife's game before It
was too late?"
"What do you mean?"
"Why. she traveled with that young
sport. Bloomer, a long time, afterward
pretending- so the women say. that
Mm tad broken with him for canse.
Palled tbe word over Melford'« eyea"
"And then eloped with the fellow I
Ou yon beet It?"
totpmsm.)
4
Fixing Responsibility
"This is a dickens of a mess I**
carped a hypercritical salesman. "This
•now has been on the ground nearly
a week. Why doesn't the mayor have
it cleaned off?"
"Well," replied Constable Sam T.
Slackputter, the faithful guardian of
the peace and dignity of Petunia, "the
good Lord sent It and the mayor Hows
the good Lord ort to dean It off."—
Kansas City Star. • ** •*"
Cuticura Soothes Itching Scalp.
On retiring gently rub spots of dan
druff and itching with Cuticura Oint
ment. Next morning shampoo with
Cuticura Soap and hot-water. Make
them your everyday ,toilet preparations
and have A clear akin and soft, white
banda—AdveHJafcSëüt
<■ Fuir Play
Little Richard HVee with hla'grand
father in Pasadena, bat he also has
another grandfather who is an artist*
a
In saying his prayers the other night
he surprised hla older slater by say
log:
"And pweas bwess my grandfathers
—the one who paints pictures an* Ute
one who doesn't"— Los Angeles Timet.
Snowy linens are the pride of every
housewife. Keep them In that condi
tion by using Red Cross Ball Blue In
your laundry. At all grocera—Adver
tlsement *
Getting Bach
"The people in thq flat above us
have a crying baby."
"Get back at them," advised the
agent "Ring."—Louisville Courier
Journal. • ■ ; - .
Don't Ask Him
Dick—"Where did you go on yonr
motor tour?" Dennis—"Oq«h ! I don't
know. I was driving the carl"
Children Cnr|
r
♦
»
I
1
I
MOTHER:- Fletcher*» /
Castoria is especially prepared V r /
to relieve Infants in arms and y
Children all ages of Constipa
tion, Flatulency, Wind Colic 1
and Diarrhea; allaying Feverishness arising therefrom, and, by
regulating the Stomach and Bowels, aids the as s i m ilation of
Food; giving healthy and natural sleep.
To avoid imitation», always look for the signature of
Abaolntely Harmlc»» - No Opiate«. Physician» everywhere recommend it
A Half-Stew
A North side man tells this one:
"I was downtown on a recent Sun
day evening and, seeing an oyater
sign on a restaurant window, I de
cided a stew would be Just about
what I wanted at that moment.
"Going Inside, I said to the wait
ress : 'A half-stew, please.'
"When the steaming plate reached
me I saw that the girl had certainly
brought me a 'half-stew,' as six halves
were floating about Instead of six
whole oysters.'*—Indianapolis News, -
Two of a Kind
He— Ali, I wish I had some of the
cakes my mother used to bake for roe !
She—And I wish I bad some of the
dresses my father used to buy for me I
—Sheffield Teleet-flnh.BH
b* 6 °
For
\
0 AYE*
/
m
•j#
X
h
ll
I
PIRI
Proved safe by millions and prescribed by physicians for
Lumbago Colds
Headache Pain
Neuritis Neuralgia
Toothache Rheumatism
DOES NOT AFFECT THE HEART
Accept only * 'Bayer" * package
which contains proven dlrections.
Haod
r "Bayer" boxes of 18 tablets
bottles of £4 sad 10O—DruggMa
Ummtuctm tt H asBs cstl ee rifaetw «(
at
Nurse Advises Women
Yakima, Wash. — "If the expectant
mother wishes to keep well and strong
I would advise bar
to take Dr. Pierce's
a Favorite Prescrip
Hk tion. It not only
K helps physically but
w mentally also tor it
ey keeps one feeling
f so well that there
.fit no need for
worry. I found it so
'very beneficial in
keeping me strong
» and well and to
quieting to the
nerves that I always recommend it to
my .patients;.apd- many of them have
taken it'with splendid results. I do not
think there is anything to equal it for
t^y weak and ailing woman. It just
seems to build up every organ in the
body."— Mrs. J. OWeal, 410 N. 4th A vs.
Al l dealers. Tablets and liquid.
v
x Green's
\ tagest Flower
fna at! potion
■ TarpM Liver
^ ■—' Relieves that feeling
of having eaten unwlaely. 30c and
90c bottles. AT ALL DRUGGISTS
Wanted, Old Fake Teeth
W» per hi«h aa
III (or full HU
Dont manor It
bream. Wa tor
•■crown», brld««%
and sold J»w»lrr.
a
Conditional
Caller—Is Mrs. Blank at home?
Green Girl—Ft you're for the bridga
party, ahe Is; If you •ain't she ain't
Corrupted freemen are the worst of
slaves.—Garrick. ],
Danger in Being Fat
"A lean dog tors long race," is an old
proverb, and a lean person for longev
ity Is a corollary that life Insurance
companies are more and more im
pressing on the public. At a national
convention of life Insurance men held
recently in Chicago, the president, Mr.
Albert M. Johnson, said that fat la
killing off Americana so rapidly that
special education Is needed. He con
siders It more dangerous to be fat
than to travel on a railway, an ocean
liner or an airplane. What temerity
It is. then, for a fat man to travel at
olll—Youth's Companion.
Forgive your enemy, especially If
he has you down.
The fool Is apt to either be! 1er*
everything or nothing.