pacific radio vol 1 5 may 1917

7/23/2019 Pacific Radio Vol 1 5 May 1917

http://slidepdf.com/reader/full/pacific-radio-vol-1-5-may-1917 1/35

VOLUME

NO.

(

'

v

•

MAY

917 EN CENTS

W

ED TO N

first

and

only Pacific Coast Publication devoted

to

Radio

Communication



"

-T,

k

*W

1

m

i B }

N O . A 2 PANEL SE T

SlirrlfU-alioni:

( • . . I I k I . ^ . I

U A K K U T K

* a l i e l

MuUiple Point battery

witch.

H o

k

mounted circular

heostat.

Three u-lnt llament

witch.

S p e . lal

'

volt

amp.

ealed i battery.

i

me

ested supersanaltlve Klectron Relay.

A l l

metal

arts

nickel

lated.

This nstmtnenl s our

unimerelal

yp e

anel et nd s nidshed nd

mounted n

he

la-st sisslble

manner.

he switches

ar e

laminated.

nsiirlng

ease

of

adjust

meld. he

heostat

opemtes without

noise

and s capah

f

Klvlna

very delicate adjusttnenl.

Th i s S et

s

Complete

with B Battery

and

T u b e

PRICE 5.50

Below e

how

an

unsolicited

etter

rom

well nown

ocal

e\per l-

tnenler

ar e eretal hundred letters of this kind reffardlnc lectron

Relav in

our

flies e lake

his

one because both stations mentioned were

workltiK

on

""

meters wave

ength

am i

using ess

han

one

kilowatt

of

power.

ienver Is

approximate^

miles rom

Burllngame

Burllngame.

Calif.

March

8 ,

9 1 7 .

Moorhead

Laboratoriea.

San

FrancJaco,

Calif.

Gentlemen:—Some

im e go

urchased

ne

of

your

Electron elays.

ant

o

et

ou now h at

am

very

leased

at he

esults have

ob-

ta

'

n

?

d

ani'

t

?oeated

at

urllngame.

Calif..

0

iles outh f San rancisco,

about 1 5

miles

from

he ocean. y call s 6 W Z .

have

been

n

th e

wireless

game fo r th e ast

ix

years and have always

owned

tation.

n this

time

i

have used

lt kinds of audlons and

mineral

detectors.

O n

Sunday morning,

M arch 2 5 .

1 9 1 7 , at

2 : 0 0

a.

m.,

worked

and

received

a

message rom 9A MT of Denver.

Colorado.

his

station

ame

n

very oud

and

here

w as

no

epeating. onsider this

very

wonderful

work

and am

sure

ou

will

agree

with me.

ongratulate

you

on

your

wonderful work

Yours

very truly.

(Signed)

A LL

BERRINGER.

THE OORHEAD

ABORATORIES

,

65

Jessie

Street an

Francisco, Cal.

When Wlitli

u

m Adveruiem

lM» e

mrntlun

his

M

ig itlne



PACIFIC

A D I O E W S

I'D

QST

MATEURS

ST

No.

20

Switch Complete

.75

Knob

only

.40

N o .

0

N o .

1

No. 21

Switch Complete

.45

Knob

only

.20

R i i l l d

your

ow n e. f - l x I n K

« -m

anil a v » - money.

andsome

nobs

n «

l i

and

Iln«*h

ami 2lin-lws in

«llanieier.

t m M i

collar

a-lfi ndi iIk^

elf-

cleanlnK switch lever

l-lv

i m h and -II Inch I o i i k liese

switches

w i l l make

any set

nik

o o

» e r

cent etter.

Club together and buy

hem

I n

o o ots at

he

following

prices:

N o .

2 0

Switch

omplete

er

0 0 6 2 . 0 0

N o .

2 1

6 . 0 0

N o .

Knob nly

0 . 0 0

N o . *

5 . 0 0

N o . 5

brass

contacts - 4

n .

- 4 apped

6-32

. 7 5

N o .

1 4

• - 1 6 n ,

- 1 6

n.

tapped -32. .

•

. 5 0

ROTARY

AP

ISCS

. -L-

B\

nch diameter , . H x f * - I f i

n .

parking

oints

Inch hick arry I ' »K apaclty 2 K .

W .

Made

of

highly

K i l i s h e « l ormica nd iime<l

Hbaohilely

rue.

iiamn-

l e e < l

ot

o

arp

or rack A " dls. epresents

our

amous d i u r d ote

rotary.

yp e

"A "

disc furnished with either

S

or

1 2

oints yp e I t l l s c

I n

6 - 8 or

1 2 i K t in l s

at no

additional charge,

'luick

drilled or -I nch

shaft.

Disc

omplete

with huck

3 . 5 0

less

Chuck

nly

Extra fo r

special

drilled

huck

up

to 3 -8 inch

3 . 0 0

.6 0

.3 0

KLITZEN IRELESS PPARATUS OMPANY

1 1 3 3 HERRICK

ST..

RACINE. WIS.

Whan

writing o Advertisers

lease

mention

ids

M agazine



I' M M C \

1 ) I <

> I 'W'S

D

R

E

C

E

1

V

Y OU

WILL

OM E TO

THEM

EVENTUALLY

SIMPLICITY N D E S I G N ENSITIVE

FREE

A T A L O G . 0

A G E S

Doubleday-Hll lectric o

7 1 0

LIBERTY

A V E .

ITTSBURG.

PA .

Put up

your

own

wireless--

make

and

understand

our

instruments,

learn

all

about

the

new

systems

and

audion

circuits—

EXPERIMENTAL

WIRELESS

STATIONS

N ew dition with Supp lement ,

1.50

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7 cents

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EDELMAN

I s he one

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hat hows

ou

ow nd ives yo u he

nformation

ight up o

date.

housands all over

th e

World

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ollowed

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nstructions

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uccess,

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ecords. ou

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urry

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w i l l come

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mail and gives just he nformation you want; ho w

to

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; *

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H r

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m iM neiialx ami miera or

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wavelenstthx.

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an*.,

uild

wireless

elephones,

elermivno

and

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ln

u l t . * ,

eceive

undamped

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wave

slsnals.

tc .

etc.,

a l l ully

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he most

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alenla

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*

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included.

SPECIAL

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RDER

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OW

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E.

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d. . 1 I

is.i

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. 1 .

a

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R

Built

for

Spark

and

Arc



p̂acific

\a6o

5 0

M A I N

ST . .

S A N

FRANCISCO

Volume

. W . Dickow,

Editor

o.

Contents

for May, 1917

Fr on t Cover .

L .

Sabo

Frontispiece,

"The Last M an, "

y

V.

Hallinan

T he

Federal

Teleg raph

Company ' s

System

9 7

T he

N ew

G reb e Regenerat ive Receiver 01

I ' . .

W l o pe Receives Naval

Reserve Commission

( 1 2

T he Vacmim Detector 'atent

Situation 0 . 1

A ll mateur

Suiions

ust

lose 06

T he

rm y

and av y

Reserve

07

N ew England mateur Association 09

A n

S .

O.

S .

n

Greek ,

B y

D .

R.

Holl ingswor th

10

Undamped

Wave

Tuners ,

B y H .

R,

Sprado. 11

Radiotorial

13

Amateur

Stations

15

Troubles

of

th e

Federal

Operator

16

D o \ ou Know 16

Copyriglu,

SI7.

Karirit-

Raitii. Pub, Co,

PACIFIC RADIO

NEWS

is publ ished month ly . ubscript ion rate

is

$1.00

er

year n he U .

S .

and ossessions; 1.50

o

Canada and

For«gn

Countries.

ingle

copies,

0

cents

ach.

or ale at

news

U

11

checks

and

money

orders ayable to

Pacific

Radio

Publishing

Compamy.

otify

us

mmediately

o f

any change n

your

address o nsure

eceiving

al l copies .

A ll communications or contributions to PACIFIC RADIO NEWS

should be addressed: ditor,

PACIFIC RADIO N E W S ,

50

MAIN

STREET. A N R A N C I S C O . C A L . orms

close on he

ifth of

th e

month

receding

month

o f magazine, as printed herein. anu-

scripts

an d

photos or

drawings

will not

be

returned

unless

ostage

is

inclosed.

.

R.

FENNER,

M anager .

PACIFIC

RADIO

UBLISHING

COMPANY

PUBLISHERS

5 0

M A I N

STREET A N

F R A N C I S C O .

C A L .

Entered

as

econd

lass

matter

S a n

Francisco, California,

March 10th, 9 1 7 , at

th e

Post

Office,

under

th e act

of March ,

1 8 7 9 .



I ' K . PACIFIC

ADIO ' F W S

jt

/

¥

V'

I ' U O M

DU A WIN G Y .

IAI.I.IM 'AK



"pacific

a6o

w

5 0

M A I N

STREET.

S A N F R A N C I S C O

Vol.

M A Y . 9 1 7

N o.

5

Tke

Federal TelegrapkCompany s

System

V

L

*

a:

\

iL

i

> r

• Li

^

KKI»KRAL

T K A N S M I T T K R

AM »

RKCKIVKR

O N

TH

K

S S

.ANSINO

There

s

no

ystem o f adio eleg-

raphy

h at as

om e

o he

ront

more apidly uring

h e

as t

ew

years

han

he

oulsen

ystem

s

utilized

y

he

ederal

eleg raph

Company

o f

S an

rancisco and

t

s

gratifying

o

o te

hat

h e

ederal

Teleg raph

ompany s

alifornia

concern

with

ts

headquarters

n

S an

Francisco

nd ts

actory

n

al o

Alto.

California.

T he

evelopment

f he

ederal

Teleg raph

ompany 's

pparatus

as

brough t

about

h rough

ollowing

he

great

advance

n

h e

cience o f

adio

te legraphy w r ough t by he discovery

by

Poulsen,

o f

Denmar k ,

o f

a

method

of

developing

ndamped

or

continu-

ous

ertzian

aves s distinguished

from

amped

aves h at ad

revi-

ously

been used by

al l park

ystems.

In ong distance

ork

t

as been

found h at ong wave engths are es-

senlial.

an d

hat,

using

a

wave

length

o f

ver

.000

meters,

ndamped

r

continuous aves o f constant mpl i -

tude

gave

elter results o r a

iven

p o w e r

h is

yp e

of

wave

can

only

be generated y n alternator

or

an

arc.

h e

lternator,

t ight eem,

would

e he

deal

ethod l

ro -

ducing

continuous

alternating current



PACIFIC

ADIO

EWS

M S

< > i i i c i i rc'iucncy

oscillations',

but

th e

l i . : <

ttliics

f

nami(actnring

nd

U M inlainuiK uch iadiinr avini;

(lie

peed

ufficient

o

roduce uch

I

ikIi

frequcncN

urrents

and

h e

act

that

er> mall

air

caps would have

lo e sed etween

he

tationary

and moving

parts

would

make

uch

a

machine

ractical

mpossibi l i ty .

T he other

method o f generating

high

frequency

urrent, amely, he rc,

w as

ound

y

oulscn

o be a ery

efficient

ne . t has

h e

advantages

> j

aving

no

moving

arts, bearings

or

mall

ir

aps;

and

hat

o

ine

m

anical

wo rk s

necessary

in man-

ufacturing.

he

ave

ength n n

ar c

ystem

m ay

be changed nstantly.

\ imple

xplanation

f

h e

rc

method

migh t

be

well

o

give.

A irect enrrent lectric rc s

niamlainrd

etween

o p p e r and

ar-

bon

electrodes

within

a dosed,

water-

jacketed

hamber ontaining ydro-

gen,

r

a

olatile

ompound

ith

large

ydrogen omponent . cross

this arc s

laced

a strong magnetic

field. n xplanation

f

he

ction

u pon

tiu ar c

o f

th e

magnetic

field

and

of he ydrogen tmosphe r e s oo

In hnical o

make

here,

but

th e

esult

is

h is

f

h e

erminals of

uch

n

ar c

be

connected,

o ne

o

he

antenna,

and

o ne lo th e

earth,

energy from he

arc

il l

be

aken

up

by

he

antenna

iu orm f

ilternaling

ulsations

of

current

h is

energy s

hen

a-

di.'ed y

h e

ntenna

s

lectro-

magnetic

aves.

he

requency

f

these

alternations,

and

herefore h e

wave ength

adiated,

s

etermined

by h e electrical

characteristics o f

th e

anlenna

circuit;

, ts "inductance"

•

uid

capacity" ,

nd

hese

re

d-

r.iM ed

o

roduce

he

wave

engths

t

is

esired

o end n h is

ysleni

th e ignals

arc

made

by a

elay

k ey

which

witches

h e

current rom

he

antenna o a ocal on-radiating

cir-

cuit. he elay s operated by n

o r-

dinary

orse

elegraph

k ey

T he

aves

ntercepted

y ,

nd

.

A

F B D K R A I ,

POUI-SEN

A RC

therefore he

currents

nduced

n

he

receiving

antenna

arc o f a requency

above

he

imits f udibility:

he

human

ear being

unable o

hear

re-

quencies

higher han

about 15.000

er

second.

hese

urrents

re

roken

up by

h e

device kn o wn

as

he

ikkcr

which

is

simply

a

piece

o f

spr ing wire

so

djusted

h at

t

il l

kick"

r

"chatter"

gainst

evolving

rass

wheel

hich

s

n

h e

haft

f

an

induction

otor . h e ctual

rinci-

p le

of

he operat ion of

h e

ikkcr

s

rather vaguely

know n an d

s ubject

to

much

discussion.

In

he

event an

operator

of a

Poul-

sen

tation esires o

ommunicate

with tation mploying he

park

sylcm

o f

adio

elegraphy

he

ses

a

device

nown

s a c h o p p e r " hich

is

merely a

commutator - l ike rotating

device hich uts

p

h e

naudible

high requency

current

n he ending

circuit nd nables he perator

f

th e

park

tation

o

ead he ignals

without

he

use

o f

a "likker."



PACIFIC

A D I O

E W S

Having

briefly lesrrihefl

he

opera-

lion

of th e system

n general

it

wonbl

probably be

o f

nterest o

h e

eader

to

dwell

on

h e

extent

o f

he

Federal

System,

h e arious

tations

hlcn

arc

perated y

h is oncern,

nd

some

o f

th e

achievements

o f th e

Fed-

eral

eleg raph

ompany

nd he

Poulsen System.

Seven

land

stations maintain

th e

un-

inter ruplcd ervice f he

ederal

System.

h e o st

owerful

tation

is t

onolulu. T.

.,

here 0

K

V.

ar c

et

s

nstalled.

Other

ta -

tions

arc th e

South S an

Francisco

sta-

tion o f 0 K , W . capacity , he

ort-

land

tation

3 0

. .) .

he

an

Francisco tation

12

.

.) .

he

I.os

Angeles

tations,

w o

n number

of 2 K . W . ach,

he

hoenix,

Ari -

zona. tation 12 K . W.)

and

h e

S an

Diego tation hich s . .

The re ar e no Federal tations on he

Atlantic

Coast

but

here

s

one

oul-

sen

tation

at

Tuckerton, N .

J here

ar e

10

merchant

vessels

carrying Fed-

eral

quipment .

he

h ip

tations

carry

lal

o p

T antennas, otherwise

th e

h ip

equipment

s

dentical

ith

th e and

quipment .

T h e

rincipal

commercial

tation s

th e one

ocated

t

outh

an ran-

cisco.

a

short

distance

from S an

Fran-

cisco,

t

compr i ses

o ne

08

and

one

440

oo l

mast

an d

h e

0

K.

W .

arc.

Service etween an rancisco

nd

southern

tations s

aintained

y

th e

tation n

he

cean

each,

shor t

distance

outh

of

Golden

Gate ,

in

an

rancisco.

F or fifteen months

th e

Federal Tel -

egraph Company has

had ts offices

in

th e Hobart

uilding.

an

rancisco.

T he

great

mprovements

n

h e

adio

apparatus in use by h is company and

which

had been

erfected

at

he im e

of moving n heir

ne w

offices were

taken

ull

dvantage

f nd n n-

tenna

w as

strung rom

he

op

o f th e

Hoba r t

uilding

o

he op f h e

Flatiron

uilding;

essages

eing

received

by

he

operator n

he

o -

o

n m

I

I

k

TRANSMITTER

FOR U SE

ON

SHIRS



2 0 ( 1

lurt

uiUlliiK "r

niniciliiite

delivery.

Other

perators end essages

th rough

he

owerful tation on

he

ocean

beach

and

hese

messages

are

delivered

t he ow ntow n

.os

A n-

geles

office of h e

company,

hereby

furnishing

a

ervice

hat

s~as

apid

as physically

possible . w o

messages

may be ent

rom

h e lobarl uild-

ing h rough he South S an Francisco

station imultaneously, o ne going di-

rectly o

Honolu lu

and

h e

other o

Portland.

t ortland

n

ntenna

has been erected

on

he oo f o f

he

Boa rd

f

Trade

uilding,

hich,

o -

gether ith

tation

ocated

t

I.cuts,

gives

a complete

ireless

du -

plex

ervice

etween an rancisco

and ortland.

nterference

an e

so complete ly eliminated

that

he

H o-

bart uilding perator an

eceive

th e .os

ngeles tation hile

he

ocean beach

tation at

S an

Francisco

is ending under ull ower ;

he

dil-

ference

n

ave

engths

eing

00

meters .

Besides

duplex

w o r k , automatic

e-

ceiving

nd

ransmitting s one

which enables

raffic

o be

handled at

a

peed

o f rom 00 o 150 words a

minute.

One

o f he atest

oulsen

tations

erected s

h e

one at Chollas Heights .

California,

hich

he

ederal

ele-

g raph

Company installed

o r th e gov-

ernment. t he im e h e

ederal

Teleg raph

ompany ook

ver

he

entire

ights

o f he

oulsen

ystem,

th e argest ransmitter

built

had

been

a K.

V .

arc.

h e

exper imental

and

development

work

carried

on

by

h is

company ince hat

im e made ossi-

ble

h e

1 X 1 K .

V.

ransmitter nstall-

ed at

h e

Chollas

Heights tation an d

th e

still

greater

3 50

K.

V . transmitter

just

eing

completed

o r

earl ar -

bor

an d

Cavite.

he

antenna

o f

h e

Chollas

eights

tation

eighs

6

tons an d as a

ag

etween

ower s

of

almost 100

feet.

This

aerial s twice

as arge s he ne h at s trung

from

h e

iffel

T o w e r n

aris

n

PACIFIC A D I O FAVS

al l about

5 miles

o f

itting an d

cop -

p er

able

av e een

aid

hroughout

th e

ailio

eservation o f 75

acres.

large

ar t

o f

h is

area

s

kep t

w et

at

all

imes

o

insure

a

good

g round

o r

th e

big

aerial.

T he hree

600- f l .

aerial

towers

ontain pp rox imate ly ne

million

ounds

f

teel

nd

re h e

largest erial ower s n

he

orld.

They re riangular n ection, h e

"legs"

being S O feet

apart

at he base

and ee t

at he

apex .

ug e

orce-

lain nsulators

mbedded

n oncrete

form

h e

ase

o r

ach

eg

f

each

lower .

h e

owers

ar e

paced

2 ( X 1

feet

apart .

h e

ending

and cceiv-

ing adius

f

h is tation ust e

practically

nlimited

ince

ts

ange

is

half

ay

around

h e

globe.

t

s

easy fo r

th e

operators to

g el

messages

front

uch

distant

points

as th e

Nor th

Sea.

T he

nitial

rial

f

he

hollas

Heights tation

rought ogether

quite

a

notable

gathering

o f

adio

ex -

per ls ,

among

hem

being r . ..

\

,

Austin, chief

radio

expe r t o f

th e

Navy

Depar tment

an d

Bureau

o f

Standards;

I.ieulenant-Conimander

Ge o rge H o o p -

er .

ide

o he hief r he

aval

Radio

Service;

. ieutcnanl-Command-

er eorge weet.

" ,

.

.;

aval

Radio

ngineer

eorge

anscom:

I .A

1 R K A

IT H

KHKItAI .

A P P A K A T IS

H.

.

Veedcr, vice-president an d gen

eral

manager

of

th e Federal

Telegraph

Company ;

.

.

uller, hief

ngi-

neer.

an d 1 .. Bur ross . uperintend-

ent. f h e

am e

oncern.

T h e

ange

o f a

5 ( 1

ki lowat t

slalion



PACIFIC

ADIO

L_J

it

c

* .

V*

4

s ,

«

i

STANDARD

RRr*EIVING

P A N E .

N E W S

"'il

is

no t

known,

bill

in-

5 * 1 kilowatt ta-

tion at South S an Francisco is ecciv-

iny cKitlarly and commercially

rom

vessels ilted

ith

ederal

ireless

at

istances

ell

ver

,

I K

M l

iles.

The Honolulu station has copied mes-

sages from

.ilvese,

( icrmany.

an d

he

steamship

entura, f he

ceanic

Steamship ompany

leet,

hile t

Sydney, ustralia,

as opied es-

sages

ent

rom

he

Tuckcrton,

ew-

Jersey,

0-ki lowal t

ederal

oulsen

arc.

a

istance

o f ver 0.000 miles.

T he IM I-kilowall tation

t

'hollas

I

leiKhls.

an

ieRO,

irlnally

ncir-

cles th e

world,

as ts aiiRe

hould

be

equal o al l he

i rcumference

t

th e globe.

n

view

f

hese emark-

able esults,

t

il l e ighly nter-

esting

o earn o f

h e

capabilities o f

th e

great

stations being

erected

by

th e

Government

n

h e

awaiian

nd

Phil ippine slands.

M A R C O N I

PERATOR

E A R S

M A N Y ISTRESS A L L S

M arconi

Operator H 1 . Lo n g , well

known

among

commercial

adio

ope r -

ators n he acilic oast, ecently

relnrned

rom a

series

of r i p s

on

he

"M anchur ia ." lying etween e w -

Y o r k

nd

ngland.

lated hat

e

heard

eight S, O. S. calls while

cross-

—ing

h e

nglish

hannel

ecently.

TKe New Grete Regenerative Receiver

T he

ew rebe egenerative

e-

ceiving Cabinet

is one

o f

th e most

dis-

tinctive on

he

market

oday.

ith

this et here

s

no

uch a

aying

as

" Beauty s

nly k in eep." very

par t

n he

nside

s

ssembled

nd

placed n a neat

and

attractive

man-

ner

nd

s built

as

ell

nside

as

t

appea r s f rom

th e

outside. ig h

grade

materials

are

used h roughou t

n

he

construction

f h is

eceiver. he

variometers

are

made very

accurately

so

that

h e

rotors

will

p in

reely

and

thus

llow-

ccurate djustment.

safety g ap s rovided o r

rotection

against burnouts

while

th e

transmitter

is n perat ion. here s o t ne

single piece

o f

magnetic

material

used

in he construction o f h is

et.

he

panels

ar e itled

o he

cabinet

ndi-

vidually

to

insure

he

very neatest

ap -

pearance.

h e

esign

f he

nduc-

tances

s

uch

h at

apacity,

nsula-

tion and magnetic

osses

ar e

educed

to

a

inimum. ll

ermanent on-

nections

re

ade ith ard-drawn

square

o p p e r ir e nsuring

gainst

burnouts between ires

hile

rans-

mitting

an d

l lowing onnections

o

be

made

n a direct

anner.



PACIFIC

R A D I O E W S

S A N R A N C I S C O

ADIO

L U B

O R G A N I Z E S

A Y

CITIES

SECTION

Comnicixiul and amateur operators

residing

n

he

vicinity

o f

S an

ran-

cisco

can

no w

enjoy he

rivilege

o f

joining a adio lub. h e ay

ity

Section f he

an rancisco adio

Club

w as

organized

several

weeks ag o

at 510

Fuclid

Avenue,

Berke ley ,

h e

constitution

as

ead

nd ccepted

and

embers

ere

dmitted o

il e

club n

arge

umbers .

ver hirty

radio operators

attended th e

organiza-

tion

meeting

and

a'bright

uture

o r

a ay

ity

ection s

lready

ore-

seen.

M r.

„

., JelTery w as

elected

Chair-

m an

f h e ection;

r.

.

quires

and

F .

O'Nei l l were elected Secretary

and

reasurer,

espectively;

.

.

Dooing as lected

ergeant-at-

A r m s

nd

our

embers

ere p -

pointed o

ac t

on

a membcrsbip

com-

mittee.

M eetings il l be

eld

on

onday

evenings

at

510

uclid

ve.,

erk-

eley,

until a permanent

club

room

can

be obtained.

A ll orrespondence hould e d-

dressed

o

r.

.

'Neil l , 635 d-

dison

t. ,

erkeley,

al.

E ,

W.

TONE

ECEIVES

OM -

M IS S IO N N N A V A L

RESERVE

A t he month ly dinner o f he

S an

Francisco

ection of

he

nstitute

o f

Radio

ngineers,

llery

. tone,

Assistant

Radio

Inspector,

w as

high ly

commended

on his uccess

n obtain-

ing

he

ank

o f

Lieutenant

n h e

U .

S.

aval

eserve.

r.

. o rd

Greaves, ocal Radio nspector ,

deliv-

ered

n nteresting ddress n

he

Naval Reserve

and

congratulated

M r.

Stone n is uccess.

e uddenly

interrupted h is

peech

y drawing

little

w o r d ade f

in

ut f is

pocke t

and presenting

it

o

M r.

Stone

stating h at e

hould

o orth o

fight o r

is

ountry nd se

he

sword

to go o d

advantage.

S A N

RANCISCO

ADIO

L U B

WILL NOT I S B A N D DESPITE

UNSETTLED

WAR CONDITIONS

T he

w ar will

have no

effect

on he

San

rancisco

Radio

Club;

his

w as

finally

ecided

t he

ast

usiness

meeting. eetings

il l

ontinue o

be

eld

n

riday evenings

and

he

month ly

ocial

meetings will be

held

as usual. ractice buzzers an d keys

will be

nstalled

mmediately

in order

to

enable

th e members

to

practice

the

code on

meeting

nights.

SUPPLY

OF COPIES

QUICKLY

EXHAUSTED

W e

av e made arrangements

ith

th e

S .

" .

N e w s

Agency

fo r

the

distri-

bution

of

copies

to

al l

newsdealers

in

this

ountry and yo u

hould

xper i -

ence

no

t rouble

in

obtaining

your

co p y

from a newsdealer. sk you r dealer

fo r

th e best

wireless magazine

an d he

will

nvariably

efer

you

o

he

"Pa-

cific adio

ews."

he u p p l y f

our

irst w o ssues

as quickly

ex -

hausted nd any nthusiasts ere

unable o

obtain a

co p y .

SOMETHING

ORIGINAL

T h e

D O Y OU

KNOW THAT—"

department

s

one

hat

as

m et

h e

app rova l of many

eaders.

e have

been

equested

o

ublish

umber

of

short

articles under this head every

month.

ld

im e ncidents, wireless

kinks,

humorous

hrases

an d ther

valuable nformation wil l be ublish-

ed

onthly

n

h is

ection

f

h e

magazine.

A L L

FEDERAL

OPERATORS

EN-

LIST N N A V A L RESERVE

A ll operators employed n he

er -

vice

o f h e ederal

Telegraph

om -

pany have enlisted n he aval e-

serve

nd

ig h

atings

av e een

awarded

o

many.



PACIFIC

ADIO

EWS

2 0 . 1

Tke

acuum etector

atent

ituation

( F r o m n

uthor ized

nterview ith

E.

unningham,

Sales

M anager ,

Audiot ron

Sales

Co.)

T w o

nfringement

uits no w end-

ing will

some

day clear up

th e

vacuum

detector patent ituation.

ue

o h e

comp lex haracter f he ssues t

stake

an d o misleading

and naccur-

ate statements hat have

appea red

n

th e

magazines

rom

im e

o

im e

he

radio

orld

inds

tself

at

ea"

n

regard o h is ituation.

esume

of

th e

facts hould therefore p r o v e

o f

considerable

nterest

o

everyone

n-

terested n adio ommunication.

These

acts ere obtained ro m

h e

Sales

M anager

o f

th e

Audiot ron Sales

Company,

r .

.

unningham, nd

th e statements

ar e

he

irst

ever

pub -

l ished rom

ata

iven

ut

y

h is

firm.

T h e radio wor ld

w as

unquestionably

but

agreeably

surpr ised

to

see

th e an -

nouncement n he October ,

1915,

s-

su e f h e

World's

dvance"

f a

new

ubular

vacuum

detector .

un-

dreds

f

voluntary

estimonials

oon

proved

hat

h is

ew

etector

ut-

ranked all others n quality, er form-

ance nd ensitiveness. or ive

months

th e

tubular

Audiot ron

had

the

field o

itself

but after that t ime com-

pet i tors

prang

p

nd

dopted h e

Audiot ron

design.

he very fact

that

th e

D e

Forest Company ,

manufactur-

ers

o f

the ound

bulb

audion,

adopted

th e

ubular

o rm

f he udiotron

Sales C ompany an d made claims o r

their "new

tubular

audion,"

not

there-

tofore made

o r

h e audion,

w as

he

best

r oo f

o f

he

uper ior i ty

of

he

Audiotron. n February , 1916,

th e

D e

Fores t C ompany

filed

uit against th e

Audiot ron Sales Company an d others

claiming

hat

he

defendants' devices

infringed

om e

igh ty- two

laims f

eight

patents

owned by

D r. D e Forest.

T he

udiotron

ales ompany , e-

lieving

n

he originality

o f

heir

de -

vice,

mmediately

etained

h e

er -

vices of M r. W m . K . W hi te , S an Fran-

cisco's eading patent attorney, chief

patent

counsel

o r

he Federal

Wire-

less

Te l eg raph

Company ,

and

w ho

s

probably

he

best osted

attorney

n

radio

patents

today.

On A u g u s t 7th and

th , 1916,

after

th e

filing

o f

many affidavits, direct and

rep ly ,

h e

motion

o r

rel iminary

n-

junction

as

argued nd udge

an

Flee t

held

hat

h e

case

w as not o ne

fo r he

ssuance

o f

an

njunction

but

that

bonds

would

be

equired o f

he

defendant

ending

inal

diudication

at

he

rial.

ailure

n

he

art

o f

th e

defendants

to

file

bonds

would

en-

title

the

D e

Forest

Company

to

a p r e -

liminary

njunction,

rovided hey

filed

bonds

n

ik e

amount

ndemnify-

ing h e efendants.

he

udiotron

Sales

Company

iled its bond on A u g -

ust

14th,

1916,

an d has

continued

sell-

ing

ts

egular

hree

member

vacuum

tube

etector under bond

ince

hat

date;

o

njunction

aving

een s-

sued

n

avor

of

he

D e

Forest

C o m -

pany. T he

injunctions

against

"maker"

and

"user"

referred

o

in

he

D e

For-

est

dvertisements

av e

o

onnec-

tion with or bearing on

he

Audiot ron

Sales

Company ' s

nterests.

l though

one

o f h e

ocal

defendants ailed o

file

a

bond

t

s noteworthy

hat

he

D e orest Company

as never

iled

its

bond

necessary o

ecure he re-

liminary

njunction

gainst

h is

e-

fendant.

After Augus t 7th,

1916,

th e D e

For-

est

Co. imited

he

action o infringe-

ment

o f

only

four claims

o f

only w o

patents.

nfringement w as no

onger

claimed

o n

eventy-eight

laims

an d

on ix atents y e orest . h is



204

ACIFIC

concession

as a decided mora l vic-

tory

nd

lso

ubstantial

ne

o r

th e

udiotron

nterests. s

yet

he

case

has

no t

been

decided

nor

has

t

even

come

o

a

rial

and

t

would

be

impossible o ay

when

he

inal

de -

cision

il l e anded

own .

he

Audiot ron

Sales

Company

has

ts

de-

fense n plendid hape and s confi-

dent

of the

inal

ou tcome o f th e

case.

In ddition o he echnical acts

of

he

ase here

re

any

more

points

which migh t

nterest

he

adio

engineer

nd

xper imenter .

hese

points

are

hose

which

hare

been

set

down n

h e

istory

o f atent

uits

an d

points about he

heoretical

ide

of h e question.

T he

irst

itigation

etween he

M arconi

nd

e

orest

ompanies

dates

back

o

1914

when

he M arco ni

Company

obtained

reliminary

n-

junction

under it s "tuning"

patent

p r e -

venting

e orest

r

is ompany

from

market ing

complete

adio

rans-

mitting

nd

eceiving

ets

tilizing

four

ircuit tuning. he

arconi

Company,

after obtaining he orego-

ing

njunction,

iled

uit

gainst

he

D e

Forest

Company

in

1914,

alleging

th e

hree

ember udion o be n

infr ingement

n he leming alve

Patent, .

.

.

o .

03 ,684.

counterclaim

and

answer

w as

iled by

D e

orest

n

ecember

th ,

914.

Kleven

months ater,

n ovember

1 5 ,

915,

and

eleven

days before he

trial

ommenced, he arconi

om -

pany

iled a

disclaimer

on

he

F lem-

ing

patent .

o

understand

the

signifi-

cance

of

h is move eference o h e

Fleming

atent il l

how

hat

t s

entitled A n

nstrument o r

Conver t -

ing

Alternating

Electric

Currents

into

Continuous

urrents."

n

884

T h o m a s

.

dison ad iscovered

that

n an

ncandescent am p

contain-

ing a

cold

late

o r

electrode

nserted

between

he

eg s

of he

ilament

and

connected

externally to a circuit lead-

ing o he ositive erminal f he

filament

a

current w as ound o lo w

R A D I O

EWS

in

h is ircuit, ut ubstantially

o

current w as

ound

o

lo w

f

he

dr-

cuit

as onnected

o

h e negative

terminal

of

the

filament. dison

ook

out

a

patent

in

1884

N o.

307031)

util-

izing

h is

henomenon.

hus,

o ng

p r i o r o

h e ate

f h e

' leraing

Valve atent, t as

ell

stab-

lished

act

hat

he

pace

ithin an

incandescent

am p

ossessed

nilat-

eral

conductivity,

that

s,

would

ecti-

fy alternating currents. s

originally

filed

he leming

atent

as

uffi-

ciently

road o over he riginal

Edison

evice

nd

aturally

as ,

n

view

f he

revious iscovery,

n-

valid

o

hat

extent.

he D e Forest

answer learly et orth h e enesis

of

he

Fleming Patent an d

hence

h e

necessity

o f he

arconi

ompany 's

disclaiming

he leming atent ex -

cep t

as used n

connection

with high

frequency lternating

lectric

ur-

rents

r

lectric scillations

f

h e

order

mployed

n

ertzian

ave

transmission."

The

Fleming

Patent

s

therefore, f anything,

merely

a new

use

or

n o ld device

ince

leming

appl ied

h e

Edison

Valve,

as a recti-

fier, o detect

adio requency

alter-

nating

currents.

he Fleming

Valve

never

has roved o be very

efficient

in

he

commercia l ield and

t

s ig -

nificant

h at D e

Fores t

h ad

been

sell-

ing

he

udion

o r

ver

ix

ears

before

h e

M arconi Company

claimed

it

to

be an

infr ingement

on

the

Flem-

ing

Valve atent.

n

heir counter-

claim

h e

e

orest ompany

l-

leged

hat

rior

o

h e

iling

o f

h e

suit

he

arconi

ompany

ad

t-

tempted o rrange n xchange f

licenses

between he

audion an d

he

Fleming

alve.

fter he

iling

f

th e

D e

Forest

counterclaim

he

M ar -

coni

Company conceded

nfr ingement

of

h e e

orest

udion

ith

hree

elements and herefore he arconi

Company

as erpetual ly

njoined

f rom

using he

bird

membe r

or

grid

of h e

D e

Forest

audion.

he

M ar -

coni Company claimed

hat

he hird



PACIFIC ADIO EWS

205

member w as

o f

no

value

o

hem on

account

o f

new engineering

develop-

ments

n

h e

leming

alve.

On

ep tember

0lli, 916,

udge

M ay er handed

down

a

decision

hold-

ing

hat

he

e

orest

udion

n-

fringed n

he

leming alve

nd

since

hat date an njunction

w as

s-

sued against

he

D e

Fores t Company

preventing hem rom

elling

heir

three membe r

audion

etector.

h e

D e

Forest

Company arc p repar ing an

appeal

ow

o

he igher

court and

Judge

ayer 's

decision

ay

or

m ay

no t be ustained. eanwhile

neither

D e

orest

o r

he

M ar con i

C ompany

can anufacture r

ell

hree

n-

ternal member vacuum detector .

A nowledge

f

h at onstitutes

an

nfringement

s

ecessary o n-

derstand

he ssues

nvolved.

claim

o f

tw o elements cannot infringe

one f hree lements

ven hough

th e

w o

lements

rc

dentical

ac h

to ach. hat

h e

am e

esult

s

secured

s

no

r oof

of

nfringement.

T h e

question o f infringement

involves

th e

uestion

f

ubstantial dentity

between

w o

devices.

here can be

no

ubstantial dentity

etween w o

devices

f

heir

espective

odes

o f

operat ion ar e aterially

different.

BrieHy he

Fleming

Valve

and he

D e

Forest

w o

member

udion

have

th e dentical lements, n vacuated

vessel, a heated

electrode

an d a

cold

electrode.

e

Forest claimed n

h e

M arconi

uit

hat

he se o f a ig h

voltage r

B"

attery, ot

h o w n

or laimed n he

leming

atent,

changed he peration f he

' lem-

ing

Valve rom a ectifier o

a elay

and

herefore

o

nfringement

exist-

ed. he M arco ni

Company

contend-

ed hat

th e

use

o f

a

local

battery

w as

well

nown

nd

as

ecessary

o r

th e

fficient

ectitication

f

he

e-

ceived oscillations. he well know n

form of

audion contained all he

ele-

ments f

he leming

Valve

ith

third ntervening

r r id lectrode.

Again h e

e

orest

ompany

t-

lempted o p r ove

elay

action nstead

of rectitication and used

he

no w

well

known est

o f

a

hree

member

audion

in which al l h e electrodes arc eat-

ed.

n iew o f

he

ac k

f demon-

strated

ommercia l

tility

f

he

Fleming

Valve

as

compared with he

audion

t

ppea r s nfortunate

hat

th e

audion

w as held an nfringement.

A

areful

tudy

f

he

e

orest

an d

arconi

riefs il l

h o w ,

ow -

ever, hat he

e

orest

ase

as

gross ly

mismanaged an d

h e

howing

which

ould

av e

een

ossible

against he leming

alve

as

ot

made.

T he

e

orest udion atents

claim

evice tilizing ensitive

gaseous

edium

n onnection ith

three

nclosed

electrodes. he mode

of

operat ion s

dependent

on

he con-

duction

f

lectricity

etween

he

electrodes

y aseous

ons. he

Audiot ron

and

imilar

vactuim

ulbs

is

a

high vacuum

device

n which

no

gaseous

medium

or

g as

ron

conduc-

tion

s tilized. h e

udiotron

s

therefore

acking n

o ne

essential cle-

ment

of

h e e orest ombination

an d docs not nfringe.

urthermore

th e

conduction

n

he nter

electrode

space s

y

eans f

tream

f

electrons

discharged rom

h e

ncan-

descent ungsten ilamcnt. he

mode

f perat ion s

herefore

lso

different

rom

that

of

th e

audion

com-

bination and a

urther

r oo f

o f

non-

infringement

xists. o

nterest

n

th e resent uit ttaches o he e-

tector

made

by

he

D e

Forest

Com-

pany

which

s

a

eproduct ion

o f

he

Audiot ron

ombination, he ues-

tion

f

nfringement

depends

on he

Audiot ron

ombination,

hat s,

he

elements

nd

ode

f

peration

s

compared

with

hat

of

he

audion

as

set

orth

n

he e

orest

atents.

A ny o ne as well as he Audiot ron

Company

has he right o

start

with

previous

discoveries,

in

this

particular

instance h e dison

Valve,

and

build

on

th e

idea and arrive

at

a

ne w

esult



2 06

PACIFIC

ADIO

EWS

in

ew ay .

leming sed

h e

Ellison alve s a ectilicr o f

adio

frequenncs

uillioul

ocal

attery)

and claimed hc nvcnlion.

e

or-

est,

y

evious

ay s

pparent ly

r-

rived

at

an

Edison

Valve

with

an

ad-

ditional

electrode

and ocal battery o

detect

adio

mpulses . f t

could

be

proved

hat

he

audion

docs

not

util-

iz e

h e

adio

requency ectification

feature claimed

by Fleming,

hen

he

niidion

annot

nfringe

he leming

Patent.

D e

Forest's

parent

audion

patent

s

well

ermed

he

nnscn

urner

pat-

ent.

t

describes

he

mode

o f ope ra -

tion in

a

mos t

complex

manner ,

which

Judge

ayer as

taled

n imp le

words

as

meaning,

"I De

orest)

il l

ry

o

ak e

(he

g as

conductive

between

w o elec-

trodes by heating he

gas

o h e

dis-

sociating

oint."

Later

atents

dded

hird

lec-

trode,

ubstituted

ilament

o r

he

gas

lanic,

and a

glass

nclosing

ves-

sel.

he aseous edium till e-

mained

he essential

part

o f th e

com-

bination nd h is s

he

art hich

th e udiotron

acks.

( T h e Audiot ron

Sales Company

wil l

be rateful o r ny nformation

e-

garding

he

heory

o f

he

ifference

between

h e

udiotron,

aving

h e

bulb

xhausted

o hat o aseous

medium

exists

(herein, an d

th e

audion

having

h e

ulb o xhausted

hat

there rc articles o f gas

air)

till

resident

herein.

ddress

communi-

cations

o

udiotron. n

care

of

a-

cific

Radio News ,

50

M ain Street,

S an

Francisco.)

LATE ARRIVAL COMPLAINTS

If

o ur

op y

oes

o t each ou

by

he

5lh of

he

month ,

kindly

no -

tify

us

o

h is

effect. his

appl ies

o

Eastern

ubscribers.

estern

ub-

scribers

hould

eceive

heir

copy

no

later han he 0 th o f he month.

A L L

AMATEUR STATIONS

M U S T CLOSE

W e

are

printing

herewith

he order

sent

out

by

ocal

Radio nspectors

to

close

he

mateur

tations

n

he

United

Stales.

Naval ommunication ervice

Pursuant

o

he

resident's ar

Proclamation,

ALL

adio stations o f

al l classes

are hereby ordered

closed

and ismantled mmediately, xcep t

such

tations

as

arc

pecifically

er-

mitted o emain n

perat ion

nder

competent naval authority.

AT,I . aerials, antennae or wires o r

radio

r

ireless

ommunication,

whethe r

o r

transmitting

or

receiving,

or

both ,

must be aken

down

and all

apparatus disconnected.

Eailure

to

comply

with h is

military

order m ay

esult in

evere w ar

penal-

tics

being m p o se d p on he wners

and hose esponsible,

nd onlisca-

lion o f

he

apparatus.

Owners

f

tations

eretofore

licensed by il e

Depa r tment

o f

Co m -

merce

are

equested o bring h is

or-

de r o he

attention

o f owners

of

un-

licensed

tations

nd

eceiving

ta-

tions

n

heir vicinity.

A ll

ederal, State and

ounty au -

Ihorities. and M unicip a l

police, are r e-

quested

o

co-operate with he

av y

Depar tment

n

h e

nforcement

f

this

order .

A ll

reports

o f

violations

hould

be

made

o h e

District

Communication

Superintendent ,

Naval

adio

Station,

S an Francisco, California.

Amateurs

need

not

ak e dow n he

poles

which support the

antennae,

but

all

ires

o r

adio

or

wireless

om -

munication

M U S T

be

taken

down

and

A L L

APPARATUS

DISMANTLED

A N D

DISCONNECTED.

In

ddition

o

he

losing

o f

he

amateur

tations

al l

ommercia l

ta-

tions

av e een aken ver

y

he

government

an d arc n ruth nothing

but

naval

tations,

ure

and

imp le ;

commercial

tations

av e

eased

o

exist.



PACIFIC

ADIO

EWS

07

Young Man

Your Country Needs

You

ow

N ow

hat

be nited tates as

m p lo y

o f th e

government . t

wil l

he

declared w ar t s

he

duty o f every

ecessary

o r

ppl icants

o

rite

o

able-bodied

oung

an

o

o in

ne

he

District

Communication Supcr in-

of

many

branches

o f

service

in either

endent

o f

the Naval District in

which

th e

avy or A r m y

Regular or R e-

hey

eside.

hose

desiring

nforma-

serve) . io n

ho

ive

n

he

Twelfth

aval

I hose

ho

ct

t nce o

btain istrict will obtain nformation

ro m

posit ions

ar e he

ne s

ho

will

oh-

he

istrict ommunication upen-

tain

he choice o f

ositions

ince

he

endent,

aval adio

tation,

an

higher penings rc

illed

irst.

rancisco,

alifornia.

hose n h e

For

h e

guidance

o f

hose

desiring icinity

o f

S an iego

south

f

5°

to enlist

w e have

made

up

a

summary atitude),

ay

p p l y

o

h e

District

of he

various

departments n hich ommunication

uperintendent,

a-

cxcellent opportunities resent hem- al adio tation, an iego, ali-

selves o

m en

w ho

ossess

a moder-

ornia.

t does

ot

obligate

o u

n

ate

amount

f

echnical

or

ractical

ny

w ay

o

wri te

o

he

Communiea-

knowledgc,

r oth , f adio eleg- io n uperintendent

f

our aval

raphy ,

eleg raphy ,

electrical

engineer-

istrict;

w hy

not write and ind out

ing,

aviation, adio

eleg raphy

as

ap -

hat n

xcellent

pportunity

rc-

pl ied

o

aircraft,

etc.,

etc. ents

itself

o

you .

Naval Reserve Force ignal Reserve

C o r p s

I he

aval

eserve

orce consists he

Department Signal

Officer has

of

ix classes

as

ol lows:

een uthor ized y he

hief

Signal

Class 1 — T h e

Elect

Naval

Reserve.

fficer of he A r m y o enlist n he

Class

2 — T h e

Naval

Reserve.

ignal

"Reserve

o r p s .

Western

c-

Class

— T h e

aval

Auxiliary

e-

artmcnt, the

personnel o form hree

serve.

ield

attalions,

ess utpost oin-

Class

4 — T h e

Naval Coast

Defense

anics, nd ne eleg raph attalion.

Reserve. he enlisted ersonnel

o r hese

our

Class

5 — T h e Volunteer Naval

e-

rganizations ggregate

even

un-

scrve. red an d o ne 701)

men,

with grades

Class

— Na val

eserve lying

nd

ay

as

ol lows:

Corps . ay

per M o.

Amateu r adio perators ould

0

M as te r Signal

Electricians

come

tinder

Class

4 — T h e

Naval

Coast

ach

7 5 . 1 X 1

Defense

Reserve.

t s

probable

h at

4

Sergeants , irst class, each. 5.00

many

mateur perators

of

ourse

7

Sergeants,

ach

6.00

only hose w ho

are

capable o f receiv- 1 5

Corpora ls ,

each 4.00

ing

at

least wenty words

p er

mimitc)

Torseshocrs,

ach

.0 0

will

eceive

ositions n he

ity

n 6 Cooks , each

0,00

which

hey

eside

nd

il l e

ble

52

Privates,

irst

lass, ach.. 8.00

to

ive

t

om e

nd

till

e

n he

9

Privates,

each 5.00



31 8

PACIFIC

ADIO

EWS

A

M aster ignal

lectrician

us t

be

n

xpe r t

adio operator

nd av e

knowledge

f

adio

apparatus; n

x-

pe r t e legraph perator nd

ave

knowledge

f

he onstruction,

per -

ation,

nd

naintenancc f

e legraph

systems,

primary

nd econdary bat-

teries,

nd

motor

generators; or

os -

sess

uc h

ualities

s

ould

it

im

to ct

s enior on-commissioned

officer o f

a ompany

o f

signal r o o p s ,

to

ct

s eader.

T he

ther

qualifications

or

ow e r

grades

h an Master Signal

Electr ician

ar e imilar

ut

h e

nowledge

equir-

ed s

no t

o omprehens ive.

Information

ill

e

urnished,

or

m en n

he

vicinity

f

S an

Francisco,

by he Depar tment

Signal

Officer.

U .

S.

r m y , Western

epartment.

an

Francisco.

alifornia. en

esiding

in other parts

o f

th e

country

m ay

ob-

tain

nformation

from

he

Depar tment

Signal fficer, f

h e

epartment

near

which

hey

eside.

Officers'

eserve

C o r p s

Examinations rc eing

xpedited

lo r pplicants or ommiss ion s e-

serve

fficers

f

h e

ine,

ith

p e-

cial

eference

o

he

ollowing

e-

quirements:

1 .

Character

nd

obriety.

2 .

ersonality,

ddress

nd

orce,

3 . eputation nd tanding

n is

conim unity.

4 .

Whether

or

ot e

s ikely

o

command

espect

of

fficers nd

n-

listed men,

5 . Whether or no t e has

dequate

education.

In

he

vent

that

h e pplicant

as

ha d

o

military

raining,

or military

training

f

ittle

alue,

e m ay

ev -

ertheless

e

eeommended

or

om -

mission

as

econd ieutenant

subject

to he 2 year ag e

limit),

provided e

inirn

#4

Just

a Side-Dsk

or

is

ollege

raduate,

r enior

n

college,

r

learly

ell

ducated

man. nd

rovided e as

emon-

strated

n

business,

athletics,

or otner

activity,

hat

e ossesses,

o

n

n-

usual

egree, h e bility

o

andle

men.

Those desiring

appointments

in

he

line

ections

of

he

Officers '

Reserve

Corps , m ay btain

pplication

blanks

by

ddressing,

nd hould

orward

their

ompleted

pplications

o

"Officer

n

harge , fficers' e-

serve

orps ,

eadquarters

Western

Depar tment , S an

rancisco, al."

PACIFIC

m

'

Hell

or

Peace

THE AW VALLEY

ADIO

S -

SOCIATION

lie

aw

Valley

Radio Association

w as

rganized

ovember

lh , 916.

Al though t hat im e he

association

only consisted

o f

six

members ,

it

no w

ha s

hirty

embers. he

bject f

th e ssociation s

he romot ion

f

wireless

elegraphy

mongst

m a-

teurs.

T h e

fficers

f

he

ssociation

re :

President,

r. alph

elm.

Vicc-Prcsident.

M r.

Parker

W igg in.

Secretary

nd

Treasurer,

M r.

ar -

lo w

Eppert.

RADIO

EWS

09

THE

NEW

ENGLAND

AMATEUR

WIRELESS ASSOCIATION

T he ew

ngland

Amateur

Wre-

less

ssociat ion

s

ive ir e

r-

ganizat ion f

amateurs n nd

round

greater oston. an y ine operators

and

wners

f

elect

pparatus

re

amongst

he

members .

h e

ssocia-

tion as

ts

r o o m s on he igh th

Hoo r

oi

ile

in. ilcne ons

om p an y

building

n

h e

heart f oston.

T w o

meetings

re

eld

ach

eek,

on e

n

uesday nd

ne

n

r iday.

Th e

uesday

eeting s iven

ve r

to o de

ractice

nd most

embers

ar e

very

proficient

in

th e

code.

n

o m -

nig raph ,

ey

nd

bnzzcr et

s

sed.

T he

ode

s

ever

en t

lower

han

twenty

words

niiinite. he

Friday

meeting s iven ve r o heory ec -

tures and

discussions

an d o

th e busi-

ness

f

he

lub.

T he

ssociation

ecently

el d

ts

first

nnual

anquet.

m on g he

speakers ere: r.

iram ercy

M axim .

resident

f

he

merican

Radio

elay eague ho p ok e n

th e development o f

th e

transcontincn-

lal

elay;

Captain

H . C.

Gawler . Radio

Inspector

fo r

th e

First

District: Lieu-

tenant

E .

I.

Blakeslei .

District

Com-

munication

Stiperintcndent; M r.

el-

vin astliam f

he

eneral

adio

Company and

former ly

o f

Clapp-East-

ha m om p an y ;

r. ichols

f he

M arcon i

Com p an y ;

r.

I.

.

o we r

of he merican adio csearcli

Company,

nd r.

. .

Iar lowe,

publici ty

manager

f he

Win.

Filene

Sons Company,

hrough

hose

w or k

th e

lu b w es ts xistence.

T he

fficers o f the

lu b

re G uy K,

Entwist lo.

President;

Wi n .

G .

Walker ,

Vice-President

and

Chief Operator;

.

D ,

W ebste r , Secretary

and

Treasurer,

and

r. rackct l .

xchange

ana-

ger .

T h e lu b

ias ave meter

which

is

n

h e

ands

of

he

hief

operator.

M r. Walker .

t ls o

has

an

exchange

dcparlmcnt

nder

r.

racket , nd



210

PACIFIC

ADIO F.VVS

a

mall ull romisiiii^ annual

apor

of

which

M r.

Bixbce s

editor.

T he

mernbers o f he club

ac t

as

a

commit tee in an d about Bo s t o n in as -

sisting'

h e

adio nspector maintain

lh e

aw .

A N

"SOS" IN GREEK

"Shorthy"

w as he

ne w

irst

ope r -

ator

on

he iner Terrific,"

h is

be-

ing is irst ssignment o a essel

as wireless operator.

n

h e

north-

ward rip rom an rancisco e

heard

om e

ar-off

hip ,

send he et-

ters

S.

O.

S .

he

operator

developed

a ery erky tyle

f

ending

nd

suddenly

l o p p e d

ending

i thout

signing

he

al l etters

f

he

hip .

"Shorthy"

as

r ightened

tiff up o n

hearing th e

S.

O. S.,

and mmediately

started

o

call

. Q .

o

ind

out he

name

o f

th e

ship

that

w as n distress.

Strange

as

t

ay

eem

e

eceived

no

r ep ly

o

h is repeated

calls but

he

entire

ystery

as

olved

p on

is

return

rom

he

orth

hen

e w as

told

by

th e Super intendent

that

it

w as

unlawful o end out a

" .

Q. asking

wha t

h i p s

arc

n

istress

hen

ap -

parently

ll

as ell.

e

as

n-

formed

o f he

ac t

h at o S . . .

w as ent

ut

a

essage

bearing

h e

Greek

am e

f Tyksos

as rans-

mitted

from a

near-by

l iner

to

a

costal

station,

he

iner's

perator

eing

p o o r sender

and paced

h e

last

hree

letters o f

h e signature

which

w as

e-

sponsible fo r "Shorthy's" reception

o f

his

irst

distress

call.

A LITTLE

REMINDER

During h e as t

w o

onths e

have

eceived

a

reat

number o f

e-

ipiests o r ack numbers o f Pacific

Radio

News''

and

n

many

nstances

have

been

unable o ill

he

orders .

T h e demand

o r

he

Pacific

Radio

News"

has been

greater than

he

sup -

lily

nd

t

herefore becomes

eces-

sary

to

start

al l subscriptions with

he

current

ssue.

SPECAL

NOTCE

Since

he eclaration hat he

United

States

s

in a state

of

war

the

directors of the

"Pacific Radio

News"

have been

in deep

thought

in egard o

he

dvisability t

continuing to

publish

the

"Pacific

Radio News"

or

not.

fter much

grave

hought and deliberation

t

has

een

ecided o iscontinue

the

magazine,

n

view

of

he

dif-

ficulties which will

arise

to

hinder

the

publication

of

"Pacific Radio

News," ntil uch ime s

he

present

war

has

been

brought

o

a

close.

t

hat

ime

t

s

pro-

posed

to

continue

the

magazine

as

before

nd

ll

ubscriptions

will

be

extended

over

he

ntervening

period.

Offices at

0

Main

Street, San

Francisco, California, will remain

open.



PACIFIC

ADIO

EWS

11

Und

ampeJ

Wve Tuners

B y

H .

R. Sprado

Tfcis article hall

endeavor

to show

as

clearly

as

ossible

he

yp e

o f

e-

ceiving

apparatus

est

uited

o

e-

ceive

undamped

wave

signals

f rom th e

high owered stations no w n ope ra -

tion

n

he

United

States,

ts

nsular

possessions,

Panama

and Euro p e .

The

wave

engths f hese

tations

ary

from

3000

meters

to

12,000

meters and

as

igher

ow e r s re

dopted hey

shall

o

oub t

ncrease

o

0 ,000

meters .

A s

he

eader

lready

nows ,

he

vacuum

ube

detector

n

ts

oscillat-

ing state

s th e most desirable fo r

un-

damped wave eception

because

t

a-

cilitates

ext remely

harp uning and,

in

he

better

t ypes

o f

this device,

very

clear ignals re

eceived

ven

th rough moderate static nterference.

A s

h e

o m m o n

o rm f acuum

tube

detector

s

urely

a

otentially

operated

device

th e

main

requisites

fo r

an

efficient

uner

using

h is detector

ar e

aximum

nductance nd ini-

mum capacity.

T o

egin

ith,

easurements

nd

calculations

were

made

of

he appa r -

ent

nductance, istributed apacity,

an d

he

atural

ave

engths f

number f olenoids f ingle nd

multip le

ayers

nd

o f

ancake

yp e

coils

f

arious

izes and

hapes

n

order

o

determine

he

yp e o f

induc-

tance

best uited.

T he pparent nductance A

as

measured by

aking

wave

ength

and

capacity

eadings ith now n a-

pacity n ircuit with he nductance

to

be

measured

sec Fig .

1),

and cal-

culated

by

he

ormula

L A

-(

« «

c

where L A

s

th e

apparent nductance,

X s h e eading on he wave meter ,

and C s

h e

capacity

n circuit with

th e nductance

o be

measured.

T he

atural

ave

engths f ar -

ious

oils ere hen easured nd

their rue nductance and distributed

capacity

were

calculated

and

he

o l-

lowing

data obtained.

A single

ayer

solenoid 6

5/6

inches

long and nches n diameter had a

natural

wave

ength o f

46 meters, a

true

nductance

f

15

icrohenrys

and

a distributed capacity

o f

0000366

microfarads.

ult iple ayer ole-

noid had

a

natural wave

length

of 100

meters ,

rue

nductance

f

72 1

microhenrys

and

distributed

apacity

of

00000163

microfarads. ancake

with

3

layers o f

40 turns

each h o we d

a

natural

wave

ength o f

46 4

meters,

a t rue inductance o f 1960 microhenrys ,

distributed

capacity of .0000307

micro-

farads. nother

pancake

o f

2 8

layers

of 3

turns

per layer

showed

a natural

wave

ength

f

15 meters, rue

n-

ductance

f

65 icrohenrys

nd

distributed

capacity

of

000015

micro-

farads.

The oregoing ata h o w s

hat

pancake

yp e o f

nductance

s

ar

u-

pe r io r

o

any

other

o rm ,

giving he

greatest

amount o f

nductance n h e

smallest

pace

nd

he

mallest dis-

tributed

apacity

er

unit

f nduct-

ance.

h e

pace

factor

s

mportant

where

uners

ar e

o

e

ade

p

n

cabinet for m

as

inductances

made

up

in

solenoid o rm would

require

mmense

cabinets especially here uners are

built o eceive wave engths on he

order

f

2,000

eters,

sing

a-

pacity

of

0 0 1 icrofarads

or

ess

n

th e secondary circuit.

A umber

f

ancakes

ere

ow

made

p

f

ifferent

dimensions o

determine

he

o rm

ossessing

he

best

characteristics

and

t

w as

ound

that a coil four t imes

deeper

than

wide

has h e mallest distributed capacity

p er unit

o f

nductance.

Fou r coils of 40

layers

with

1 0

turns

p er

ayer were

ade

up ,

w o

eing

used as he

primary

and w o

for

he



212

PACIFIC

ADIO

EWS

7

Wave Meter

"7

F

Cl"

FIGURE

Aperiodic

r cw t

PfW- '

secondary.

Suitable

ap s

were brought

out ,

hat

is ,

on

he

r imary every

en

turns

o r

00

urns

hen

very

0 0

turns

fo r

7 1 1 0 turns and on

th e

second-

ar y coils

taps

were

brought out

every

. 1 0

turns o r

1 0 0

urns

hen

every

S O

turns

or

50 urns or he

emainder

of

th e

secondary

winding.

These coils

were

o f 6;- j

nch

nside

diameter an d

X

inch

outside diameter

wound

/

inch

thick. umber 2 0 enamelled

wire

w as

used

h roughou t .

The

ustin

ircuit

as

se d

s

shown n

igure

and

he

ollowing

capacities were ound

best in their

e-

spective

circuit; econdary condenser

. 0 0 1

aximum,

r id

ondenser

0005

maximum,

plate

to

filament

condenser

. 0 0 1

aximum,

and r id o

ilament

condenser

0005 maximum.

T h e above coils an d capacities were

mounted

n

a mahogany

cabinet

with

a

4

nch

akelile

ilectro

anel

s

sh o wn

n igure .

h en sed n

connection

ith

w o wire

ntenna

I S O eet

high

and

6 00 eet ong,

Han-

over (GUI)

w as copied

clearly

in

day-

l ight n an

rancisco i thout

h e

use

o f

amplifiers.

mong

other

ta -

tions

eceived

ere

arien,

anama,

Chicago

XAJ),

onolulu

KHX

KIF),

Arl ington,

and

Tuckerton.

Large

ir e

s

f he reatest

m -

portance especially o n

he

o ng wave

lengths

w he r e a la rge

number o f

urns

ar e

used,

and

o r

h is

eason

h e

N o.

20 enameled w as

chosen

as

h e

otal

resistance o f

he econdary w as

only

1 2 . 4 5

o h m s

as

compared with

90

o h m s

when

o . 8 ir e

as

sed. f

course,

arger

ir e

till

ould

ave

made

n

mprovement

ut

ith

he

p resent

rice

of c o p p e r

t

w as

ound

almost

prohibit ive.

i tzendraht is , no

doubt ,

h e

deal ir e ut s ardly

within

he

each f he

average

x-

perimenter .

In

h e

onstruction f ndamped

wave

receiving

sets

here

is

one

point

to

hear

n

mind

an d

hat

s

A X I -

M U M

NDUCTANCE

WITH

MIN-

I M U M

A P A C I T Y

ETWEEN

WINDINGS

s

h e

only

roducer

of

th e

best

results

and.

as exper iments

show,

he

ancake

ype nductance s

th e

est

orm

or

obtaining

he

e-

sired

result.

m

00/rf

/

/

vw xxn /

'

o o o 6 rr

7 * / .

lilih

_est±i



PACIFIC

A D I O EWS

RADO

O

R

B y

the Editor

M any

years

ag o

he

problrins con-

fronting

lir

amateur w ho

l a l > b l e < l

n

th e

mysteries

o f

ireless elegraphy

(as

t

as

hen

alled)

ere

ndeed

very

nnerous. n

he

ery

irst

place, at

hat

ime,

iterature w as

no t

available n

h e

ubject

nd p p a r -

atus

w as

either

not

o

be

had

at

ll

or

else

as very high n ost .

ut

th e amateur

o f

hat

im e h ad

o ne ad-

vantage

which

many

o f

us today

wish

lo r every im e w e ut

h e

phones on

and

hrow

n

h e

aerial

witch.

hat

advantage, ractically unknown

o

ns

today,

w as

th e

absence of needless in-

terference. The modern amateur does

no t

or ry about h e construction o f

h is apparatus , th e purchase o f th e ma-

terials

herefor ,

he

esign f is

apparatus and he assembling

of

he

parts

o f he omple te et

early

o

much

as

he orr ies

when

he it s at

th e able o f is

inished

nstallation,

hears about

iftcen

other

amateurs

on

assorted

wave

lengths from

three

hun-

dred

maybe

w o

hundred)

o everal

thousand

meters

al l rying o alk

at

once. t causes him o

wonder

w hy

he

ever

constructed a transmitting

set

being

oo

iscreet

o

ry

nd

o rk

through

such

umul t

and

confusion

n

th e

ther. f e as n nalytical

mind he

m ay

he

able

o

athom

a ew

r

o f he easons

o r

he nterference.

W e

have

heard

many

amateurs

peak

in an

antagonistic

and

atirical man-

ne r about

h e

amateur

w ho

asks

about

bis

spark ,

bow

be

"comes

in,"

whethe r

be

hould

aise he

one

o f

h is

park

and

o or th .

hese

mateurs

ho

criticise

nvariably rc he elaying

"bugs" and

magine

he

ield of

ama-

teur

radio

eleg raphy

s

open

o r

re-

laying

nd

elaying

nly.

y o

means

do

w e ecognize he

malicious

interferer w ho

spends

al l

o f

bis

spare

time ith om e

oor ly

ade

nd

timed apparatus asking

everyone

w ho

can

hear him (usual ly

those within th e

radius o f a half

mile)

ow

h is pa rk

is when he himself

can

hear

t

s

arc-

ing

o

badly

hat

he g ap

s burning

up ;

but

w e

hink

t

hould

ndeed

be

legitimate

o r

n mateur perator,

w ho has

pent

om e

o f bis im e o -

ward mproving ns pparatus , per-

haps building new

arts,

rying

orig-

inal

deas,

or

ne w "hook-ups" '

and

he

like)

o sk

ellow

mateur ,

y

radio, f bis ransmitter eems o

live

tip to certain

cogitations which

he had

in

ind

hile

iaking he

aid

m-

provcnicnls

on

h is

apparatus .

elay-

ing

s, o

oubt ,

ery

eneficial

o

th e

rt

f adio elegraphy

ince

t

stimulates

ransmitting

an d

eceiving

over o ng distances under very diffi-

cult

onditions,

amely,

ithin

h e

limits

o f

short

wave

engths

an d

ow

powers ,

ut elaying, s xperience

shows ,

eems

always

o nvolve

oo

mueb

f h e perator's

ersonality.

B y

ersonality

e

ean

hat

hose

amateurs

w h o

rc

appointed

s

o f-

ficial"

elay

tations et deas

hat

I

bey

re bove he

rdinary

un

t

human

beings and

have

he ight , be-

cause hey arc

official,"

o bold

he

ether with ndisputable

r iority. Thus

i t

s

h at ersonality

offsets

mos t

o f



2 14

PACIFIC ADIO

E W S

th e dvantages o f amaleur adio

e-

laying.

W hereas

here

once

w as peace

in

ethereal

domain

amongs t

amateurs

there

no w

s

constant

war .

ut

h is

A

rivalry

between

he

elay

bug"

and

th e exper imenting amateur

s

not

he

only

discordant

rouble . e

ar e

be-

ginning

o

ee

he dawn

of till

an -

other

vil,

and

hat,

he ivalry x-

istent between

th e

relay

leagues them-

selves.

s

yet

this

has not

developed

into

ull

eriousness

ut

im e

il l

soon rove he ruth f h is tate-

ment.

e

have

thus

ar

o ld

only

o f

th e

causes

o f

interference; it behooves

us, then,

to

sugges t

a

remedy. o

be-

g in

with,

w e

believe

th e United

States

Government as een

he

rganizer

of

h e

greatest

relay

eague"

o f

al l

and

that

they publ ish

one

o f th e

most

complete ists

o f amateur stations n

th e nited

tates

hich

inds

h is

"league"

together. The

United

States

Government

list

of

radio

stations

rep -

resents

he universal ro therhood o f

radio en

n

h is ountry, o o

speak,

nd he overnment oes

al l

that s ecessary n he

ine

f r -

ganizing mateur tations; hen

e

can

ee

no

use

for

further organiza-

tion.

n a

ew

words ,

w hy

not

N-

DIVIDUAL RELAYING?

et each

amateur

elay

essages

when

e

o

desires

or

if

he

is

o f

an

inventive

turn

o f

mind et him construct h is appa r -

atus

and

hen

p r ove ts

wor th by act-

ual tests.

There

ar e

often t imes

when

an mateur eels

nclined

o

esign

and build

new

appara tus , hen, when

this

s completed he

m ay

opera te

h is

set

an d

have

occasion

o

elay

a mes-

sage

or two . f amateurs would

relay

individually,

without affiliations with

sub-organizations,

elaying

ould

e

carried

n

uch

o re

fficiently.

Imagine

a relay eague consisting o f

every mateur

icensed

y

he

o v-

ernment in

he

United

States an d un-

hampered

y

ival ub-organizations.

T he

scope

of

relay

wo rk

among

ama-

teurs

by

ndividual

elaying

would

be

increased

o ne

hundred

fold. nterfer-

ence

would be

cut

in

half

because

that

"ofricial" amateur would be no m o r e

and

ach

mateur

ould

e

ust

simply icensed mateur perator

and

hat lone. oreover , i thout

sub-organizations

here

would be ess

unnecessary

transmission of messages.

If here s elaying o e done

w hy

no t

make

it

p lay a

useful part n

daily

business

ife

nstead

o f

a

lay-toy

n

th e ands f dlers?

here

s

he

w ay

w e

could

cut

down

another

twen-

ty-five per

cent

o f

h e

nterference—

by

he

ransmission

f messages

of

more

commercial

value

nstead o f

he

transmission

f idle rattle." ut

lastly,

here

emains

he

nterference

caused y

he

mateur ,

ommonly

referred o

as h e

ham,"

w ho

nsists

in

communicating

with

another

ama-

leur

(o f

th e

same

kind) about nothing

in articular.

here

s

no

ecessity

fo r

w o

amateurs

iving

a

ew

blocks

from o ne

another

discussing

h e

after

effects f

om e

ild

orgie

n hich

they

h ad indulged

h e

night

before or

something

equally oolish. his

kind

of

interference

is

th e

most

difficult

to

cope

with.

n

some

cases

insistent

o f-

fenders might be

visited

by a ew of

th e

o re erious

and

iscriminating

amateurs

and quietly

talked

to .

fter

trying

h is

method

wice

without

suc-

cess

h e

alicious

nterferer

hould

be

r epor ted

to th e government author-

ities. n h e matter o f reporting o

th e government any malicious nter-

ferers

t

ould

e

ell

o

arefully

consider hether he

ase

warrants

repor t ing or not. e must emem-

ber

that

th e radio

officials

o f th e

gov-

ernment av e ar reater

mount

of

work

on

hand

han

merely

attend-

ing o mateurs .

ut nterference

M U S T

B E

STOPPED

or

if

it

is not

there il l

om e

he im e

hen

he

United States

wil l

boast

of their

ama-

teurs engaged

n adio elegraphy

no

longer,

an d

icensed

amateur nstalla-

tions hall no onger exist.



PACIFIC

ADIO

E W S

Amateur

tations

.'15

i

11

II

1

•

•

'

i

T

I

i-

•

T H E

S E E F R E D

BROTHERS '

RADIO STATION.

D O S

ANGELES , CAL.

-

(6AGI

A U L

.

CLARK'S A M A T E U R STATION. SA N JOSE.

CAL.



216

PACIFIC

ADIO

EWS

ris

L

IS

• v -

W ( X i l > E R »

i

I H t

M f t T

nev^Acc

r

r

J O S T

o u

Or

C Q l

(1

Y V

%

C C T

T M C

f M E W i

R U T

\

pom

susw

siat

T M O T S

I . 'C

( » 1 0 C N F . ' 0

. . I

m b w m

E

I I

S C V W

S T

P f i f ,

Ju l ro j

anmmncinnE

troi iu.ks or Tin-: --i:iii;i al oi'Kit

5 5 5 o ~ 4 * w n A

\ ' I '*

1 1

•

Do

You

Cnow

THAT

jic

dielectric

s

under

greatest

train

n

a

condenser

near

th e

edges

o f he conductor?

THAT

a

great

umber o f

mall

condenser

lates

are aid

o

be

more efficient han

a few

arge ones,

even

t hough the total

capacity

be

h e

ame,

or

he

mall

nes can ischarge

more

apidly?

THAT

he

effect

o f

a magnet on an

udion

o r

oorhead

Tube

often effects

he

uning

o f

he

eceiver?

THAT

he actual

effect

o f he

magnetic

ield eems

o be

hat

t

changes

he

direction

of

h e electron

lo w

rom

he ila-

ment,

nd

h is

hanges

he

ntensity

f

he urrents

flowing?

THAT

he

otential

t

h e

p p e r

r

ig h

otential

nd

f

n

antenna

often

reaches a

value

o f

75,000

o r

100,000

volts?

THAT

om e of

h e

stations

established

by

he

o ld United \\ ire-

less

eleg raph

ompany

ere

or

verland

ommunica-

tion only, n

competit ion with

and

ines?

THAT

at he

station

o f th e

o ld

Pacific

Wireless Telegraph

Com-

pany

on

t.

Tamalpais

a pa rk

oil

w as

nstalled hich

had

a

core

over

twenty

feet

ong,

and

about hree eet

n

diameter,

an d

extended

outside

o f he

tation

building?



PACIFIC

A D I O FAVS

217

>

\

YKS'

T 'S

H I ' M AN

SomeOperators

Still Use Galena

They

will

continue

to

do

so

after

usinj} our

silver

lated

pring

detector

ire

nd

our

Galena

E f f i c i e n t

Drtec lo r W i re i

inch

p i e c e

S . I O

E f f i c i e n t Galena, p e r ounce 2 0

EFFICIENT

RADIO

APPARATUS

CO.

1 3 3 8

M a s o n i c

A * e . ,

S a n

Franciico

100

Times

Amplilication

M ay

be

h ad

with

th e

Paragcn

RA-6

Amplifying

Short

Wave

Receiver

There

are

no

end osses

and

no

short

circuited

urns;

No

witches

and o

uning

capacities n

he

udion

circuits;

Amplification p o

0 0

times may

be

had, using

vacuum

detector

only,

and

the

selectivity s

as

great,

comparatively,

as

he

am-

plification ;

The

weaker

he

ignal,

he

greater he

mplification,

and

the

greater

the

ampli-

fication

he

reater

he

selectivity.

The

PARAGON"

A-6

is

covered

by a

year

satis-

faction - or-your-money-back

guarantee.

FURTHERMORE,

we

guarantee

the

RA-6 to do all

we say t

will

do,

and

o

so

far

xcel

ther

hort

wave

receivers

hat

here

s

o

comparison.

Range 18 0

to

58 0 meters

Price

$35 . 00

Send stamp

for

Bulletin,

"O"

Adams

Morgan Company

5

LVIN

L A C E

U P P E R M 0 N T C L A 1 R .

. J.

When

wrillnK

< >

A dvr r liM rs

lease

menllun

his M ngazlne



218 PACIFIC

A D I O

F . W S

New

alcun

olded

ubber acuum

Detector anels

Rheostat and otentiometer

Mounted

n

Back

A ll

Parts

N

ickeled

Controls

and

T

ermlnals

Marked

C a n

e

Used

With

Any

Make

T 1 1

b e

T he

E W A L C U N anels ar e

composed

of olded

composi -

tion imilar o elephone

eceiver

caps.

hey

will not

ade

o r dis-

color with use

ik e

hard ubber . he entire Panel s molded at o ne

pressing ith aised

cales

nd

ettering. h e

dges re

eveled

and

bearings

o r

switches

are

molded

in .

a

particular

feature

no t

os-

sible

with ubber

or

bakelite anels.

PRICE L E S S B

BATTERIES

OR

TUBE

N o. Potentiometer Control as cut) 10.00

N o.

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attery

ontrol

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Panel

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5 n. high

B o t h

Filaments

C a n

e

Lighted

A t

Will

W c

can

also

up p l y

he above

anels

mounted

n

and

ubbed

Quartered

Oak

or olished

M ah o gany

Cases,

complete with

at-

teries,

i ther a p p e d

r

otentiometer

ontrol .

hese

ets

re

arranged so

hat

th e

case

can be removed without disturbing

th e

wir-

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making

h e

nserting

of

ne w B Batteries

a

imp le

matter .

an

be

used with

any make

o f

ube.

PRICE L E S S TUBE

N o.

0B otentiometer ontrol omple te n

ak

ase

19.00

N o 0 B a p p e d B

attery

complete n

Oak

Case

0.00

N o.

M B

otentiometer

ontrol

n

ahogany

ase

1.00

N o.

M B

T a p p e d

Control n

M ah o gany

Case

2.00

HALLER CUNNINGHAM ELECTRIC CO.

428

A R K E T

T .

A N

R A N C I S C O , A L .

Lxclusivc

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Order Distributors

Universal

W ireless

o

an rancisco

When writing

o

AdvertIsers

lease mention

his M agaxlne



PA C IMC

ADIO

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Oasslfled dveriisements

Advertisements in this

ection

ar e

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Remittance, n o rm o f currency, money order or

t amps

ust

accompany

copy .

Advertisements

o r he

M ar ch ssue must each

us no

later

han

February 1st n order

o

nsure

classification.

In counting words, count name an d address.

Figures count ive o he wo rd n o ne g r oup .

T he

"PACIFIC

RADIO NEWS" being he

irst

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publ ished on the Pacific

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on

radio engineering

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operating ubjects

an d

not

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nfluence

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w ay

ts editorial

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exceeding

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o f

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ts

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ection.

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Communicate with « .

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B A R C A

IN S T H A T A RE

N EV ER M A D E

T W I C E —

When we make a pecial ofter

in

his

and

other

publications

It s

eallv

a SPEC A

I.

OFFER and

is

H i e besl value

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f you order your

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wilhin

thirty

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ollowing

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vacmmi

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apparains: akelile

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•

ith

ouble

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ested

Electron

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omplete ood anel

eady

or

use

and

upplied

ith igh voltage hal-

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ne uuble

ilament

ested

E'ecimn

elay

RE E IT H H IS

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LIMITED HPPI.T, - I l e c t r o n gencies

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H E R E

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OOKS

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h e

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ou

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opy.

Electric Wiring, by 1 . Branch 2.00

Electricity

at

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Frequencies

. 0 0

Alternating urrenls implillcd.

. ,

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' 5 0

Prepaid

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ACIFIC

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DIO PUB. O . . San Francisco

ON E OSITIVELY

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oorhead

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JOIN T H E .

ADIO

CLUB

dress Secretary, 1 S Halght

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OSCILLATION

TRANSFORMER

brass

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EXPERIMENTERS.

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1 6 0 c. apacity, ostpaid, 0

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Chemicals

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ostpaid. o

tamps

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Wrlk-

our ants.

tudy hemistry

now. mall hemical aboratories rom

$ 1 . 2 5

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atalogue

or iamp.

enith

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WAHOQANY. ARD U B B E R , nd

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yp e

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1 2 .

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en-

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lubes.

tamp

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ew

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radio apparains si

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big

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lso sk c o nclude

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Famous

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When

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PACIFIC A D I O

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D̂UCKS IG

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and

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Y ou hen

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exper i -

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A sk

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TYPE

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onini m i j i -

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H.Mlfs

^

i .

u i k

I

a

-

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troileii

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he

use

« i f

•

upper

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l e « trtHles

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heir

un-

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opper

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heal away ro m the sparkiiiK H i l l faces. A l l

advanced adio

niflneers oncede

hat

copper

I s nnsnrpassed or e l e «

Irodea.

ap

equipped

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i » r

use

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U N D A M P E D

LOADING

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Hear he rc

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econdary

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7 5

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llicse ndamped

oHiiers

t

$ 1 0 . 0 0

a.

h

o

2

ami

N o

2 X

Silk CtiAered Wire

I s used

o n rimary nd econdary.

r e s | » e (

lively

ariation

f

Imluctanee

I s

by

means of 2 0 point nstru-

ment

type switch mounted on n . hake-

llle. ith n rdinary oose oupler

wave ength

S . 0 0 0

meters.

$ 2 4 . 7 5

Prepaid o

any ar t

of

U. S .

or Canada

K \

e r y

orth while

eature

s noorporaled n

this

Kexeneralh e Set nitial ests

in

our

labor-

atory

mi

t

he

> M - a l

cott

HkIi

chool

brotiKhl n

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emaI'kahie

learnesa

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stations n

Texas, xmlslana, Wisconsin and all

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tales.

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siirfmssed

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other

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ested n

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have no

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clalmlnK

fo r

his nstnimern

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act

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wave

lengths

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x 0

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meters.

Case

n .

1

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n

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ubbed

i i i H l i o g i i u s

inish.

anel,

olished

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et

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ariable

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his

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elimhiHllon

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hereby

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he

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ange. rimary

• In ull adjustable by ingle urns rid mhic-

tance djustable y

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pecial

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ariable

ondenser

ncluded

n

ircuit or lose

(lining

S O M E TARTLING REDUCTIONS

FOUND

N

CATALOGUE

1 educed

Thordarson

lexible

rice

Step - 1 'p

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6 . 5 0

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. S . « n

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Note

hordarson

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live

e-

vice

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with

ach

ransformer.

Commercial Type Oscil-

lation

Transformer

Oscillation

ransformer.

Receiving

Set

with

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Receiving

Set ess Con-

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'elector

Stand

Navy

yp e

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Transformer

Arlington

eceiving

Transformer

Arlington

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e-

ceiving Transformer

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Receiving

Transformer

U , nch Spark Coil

V j

hu h

Spark Coll

I

'elector Stand

Standard

Tuning

Coll. . .

Pancake

1 e l I x

Kleclrose

nsulator

...

Fleetroae nsulator

Kleclrose

nsulator

...

T v

pe

T y

pe

T\ p e

T-o

T

- 1

T .o

N o . A 3 9 5

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N o Rll

No Rll

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1 9 1 5

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N o

1 0 9 1

N o

1 0 9 2

N o .

A

7

7 2 1

N o 3 9 X "

N o .

4 0 X «

N o .

A

6 0 1 2

N o . 6 1 X 1 0

N o

A

5 6 0

N o 7 1 X 0

N o

7 3 X 0

N o

1 7 X o

5 . 0 0

1 3 . 5 0

6 . 7 5

5 . 7 5

3 2 . 0 0

2 9 . 5 0

2 1 . 0 "

2 2 . 0 0

2 . ' M l

1 . 5 0

1 9 . 5 0

1 7 . 2 5

9 .

I N

7 . 5 0

7 2 6

6 . 5 0

6 . 5 0

5 . 7 5

2 . 2 6

2 . 0 0

3 . 1 5 2 . 6 5

.6 5

. 5 5

3

6 0

3 . 3 5

1 . 5 0

1 . 4 0

.3 0

• 2 7

.2 0

. 1 8

. 5 0

. 4 8

THE

WILLIAM B.

DUCK

CO,

219 - 223 Superior Street

Toledo, Ohio



i

doTRON

S he

Only

Original

nd

Genuine ubular

Vacuum

Detector

—

Amplifier

—

Oscillator

r . ' ,

i

\t

Patent

A pp l i ed For

T he

udiotron

as

mashed

al l

ecords— Seatt le

op ies

OU T

n

daytime

with

one

ube.

our

eceiving

ange

will

e

more

h an

doubled

f

you equip

you r tation with

h e

genuine

A u dio T r o n— no t

imitations.

T he

nternal

ction r

ode

f peration,

o t

h e

echanical

st ructure ,

determines

h e quality

and

ensitiveness.

he

Aud i o T ro n

differs rom al l

other

bulb

or ubular detectors ince t

utilizes

h e

variations,

roduced

by h e

mpressed grid otentials, n a

ure

elec-

t ron

llow

from

negative

incandescent

tungsten to

a

cold

posi t ive plalc.

Its operation,

n

no way, utilizes a ensitive

gaseous

medium.

T he

enuine

lectron

perated

ud ioTron

s ot

"so-called

AudioTron" .

Radiotron

or

other

form

o f

tubular

detector.

he

genu-

ine

AudiTron

bears

that

name.

o

not

be

misled.

Double Filament Audiotron 5.25

Guaranteed

uper-sensitive

s

etector-amplifier-oscil lator

Delivered

ree

by express

when

cash

accompanies

order

Send

o r

catalog

of

vacuum detector

anels

and

accessories

Bi gge s t Values

Ever

Offered

AudioTron ales

o

315 Lick Building an

Francisco,

Cal.

When writing to Advertisers lease mention

his

M agazine



Now

s he Tme

o

Buy You

Apparaus

• -

•

F -

e

G

\yL

R©

l

O F F

(fc*

® ©

•

Radio Apparatus

will

ndoubtedly e

dvanced

n

rice

within

a

short ime.

uy hat new Audion Set now

and

ut

t

away

until

he

war

rouble s settled.

ELECTRON

ELAYS

PANELS

F

LL

YPES

VACUUM

UBE

CCESSORIES

ND

HIGH

VOLTAGE ATTERIES

Black

inish anel

Complete

with Double

Filament

Electron

Relay,

"B"

Battery,

All

Switches,

Binding

Posts

and

Other

Acces-

sories.

ompletely

Wired or

nstant

Use.

ilament

heostat

Mounted on Back

of Panel. 0

Point

"B"

Battery

Switch

10 .00

Bakelite anel,

Circular

rheostat,

witches, B" Battery, tc.,

ready

or

nstant

se.

omplete

or.

15.50

Send

for Descriptive Circular

and

Mention "PRN"

45 Volt.

Amp.

"B" Battery. Sealed 4 . 0 0

Genuine

Tested

Electron

Relays,

Double

Filament

.0 0

Let Us Quote rices on

AMPLIFIER SETS and LONG

UNDAMPED

WAVE APPARATUS

Buy Your

Apparatus Before

he War rices

Take Effect

WARNING:—No

Genuine Electron elays Are Ever

old

or Less

than

$5 . 0 0 .

eware

of

Imitations.

ELECTRON

GENCIES

O

4 6 0 8

8th

ST..

SAN

RANCISCO, CAL.

pacific radio vol 1 5 may 1917

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