The Electrician : the oldest weekly illustrated journal of electrical engineering, industry, science and finance, Vol. 139, No. 14 (3616)

T H E

f C T R I C I A N

e r r a n t i

F E R R A N T I, LTD., H ollinw ood, Lancs. L o n d o n O f f i c e : K e r n H o u s e , Kingsway W . C . l

'

3 O C T O B E R 1947 S I X P E N C E

STEEL S T A M P IN G S

S E V E R N W IL D E N IR O N W O R K S . S T O U R P Q :

Electrical steel laminations for all types and sizes of motors , generators and re­

actors. Complete assemblies.

THE E LEC T R IC IA N

THE E L EC T R IC IA N

IT CAN S E E M L I K E

C H I L D ’S PLAY

With a good testing instrument you can make fault finding on a defective wireless set seem like child’s play. The Weston Model E772 Analyser will meet all your normal radio servicing requirements and will save you time, trouble and money. This instrument is simple to use and is

both accurate and reliable. It has a wide range coverage with a sensivity of 20,000 ohms per volt on all D.C. ranges. Please write for full details.

S Y S T E M A T I C S E R V I C I N G S T A R T S

HA W E S T O N

S A N G A M O W E S T O N L T D . E N F I E L D , M I D D X .

T e le p h o n e : E n fie ld 3434 & 1242

A

3 OCTOBER 1947

THE E L E C T R IC IA N 3 OCTOBER 1947

/ » PR ESSED C 0PPER

SERVICE BOXES

B R IT ISH IN S U L A T E D C A L L E N D E R ’S C A B L E S L IM IT E D

N O R F O L K H O U S E . N O R F O L K S T R E E T . L O N D O N W .C .2 DESCRIPTION

NOTES ON JOINTING

BOX CAPACITY

A

COMPOUND FILLING

A

BOX DIMENSIONS AND DATA

C R E A T I V E C O N S T R U C T I O N I N L I G H T M E T A L C A S T I N G S I

The principal dimensions of these two switchbox castings are 21" x 16" and their weights in strong alum inium alloy are 6 8 lb. and 39 lb. Alum inium all-oy castings are recom m ended for all such applications in which light weight and ease of m ovem ent are desirable charac­

teristics.

RENFREW FOUNDRIES L td

3 OCTOBER 1947 THE E LEC T R IC IA N

T H E M ICANITE & IN SULA TO RS COMPANY LTD.

Em pire W orks, Blackhorse Lane, W altham stow , London, E.17

Manufacturers o f M I C A N I T E (Built-up Mica Insulation). Fabricated and Processed M IC A. P A X O L IN Lam inated Materials. E M P I R E Varnished Insulating Cloths and Tapes. H IG H V O L T A G E B U S H IN G S and T E R M IN A L S . Distributors o f Micoflex-Duratube sleevings.

THE E L E C T R IC IA N _y OCTOBER 1947

969

T here is a “ K E I T H - B L A C K M A N ” F A N for every purpose for which a fan is essential.

3 OCTOBER 1947 THE E LEC T R IC IA N

HEATING V ENTILATIO N D U ST REM OVAL FORGE B LO W IN G M EC H A N IC A L DRAUG HT

FUMES REMOVAL STEAM REMOVAL C U PO LA B LO W IN G

SM O KE REMOVAL FURNACE B LO W IN G

DRYING, C O O LIN G

etc.

vKEITHv'.

iBLACKMANk

L

M I L L M E A D R O A D .

J

Y \ L O N D O N , N.I7y /

•PM O N I: TOTTENHAM « S2 2 . 'CRAMS M ITH BLA C. PMONC.LONOON.**

W e in vite y o u r enquiries.

The LINDLEY THOMPSON TRANSFORMER & SERVICE

THOMPSON R E L IE F CH AM BER (PATENTED) !

D iap h ragm and C o v er.

T em p er a tu re C alibration F illin g Pipe,

O ff Load T a p p in g Switch

NO MOI S T U R E NO S L UDGI NG

OF OIL NO SERVI CE

COSTS

CO., LTD.

600 K V A 3# 50 ~ 11000/400 Volt*.

PART O F A G O V E R N M E N T C O N T R A C T FOR IN D IA

Designed to give

TROUBLE-FREE SERVICE under DAMP and HUMID CONDITIONS.

T h is ty p e o f u n it is o p e r a tin g p erfectly in

INDIA , E A ST & W EST AFRICA,

MALAYA, EAST INDIA, ETC.

A P P L Y F O R B R O C H U R E T O : ~

ST. M A R Y ’S R O A D , M I D D L E G R E E N , S LO U G H , B U C K S .

T e l e p h o n e . L A N G L E Y (^{b u c k s}) 2 0 0 / / O !

THE E L E C T R IC IA N 3 OCTOBER 1947

971

C R V S E

S A T U R D A Y

NOVEMBER 8TJ

CRYSE

B I R M I N G H A M B U R Y S T E D M U N D S L E E D S L O N D O N B R I G H T O N C A R D I F F L E I C E S T E R M A N C H E S T E R B R I S T O L G L A S G O W L I V E R P O O L N E W C A S T L E

L C O L I M I T E D , K E M P S T O N W O R K S , B E D F O R D

M A D E I N E N 6 LAN D

The building was begun in 1074 by Remigium, the first Norm an Bishop. St. Hugh, the Carthusian monk, was consecrated Bishop in 1186

^ 'u t/n c J ts

F I F T Y Y E A R S O F Q U A L I T Y & S E R V I C E

L IN C O L N C A T H E D R A L

3 OCTOBER 1947 THE E LEC T R IC IA N

THE E L E C T R IC IA N 3 OCTOBER 1947

973,

\A\\N\\\\\\\\\\V1 ' ' urn- » HI).../fiU //j

C .M .A . cable has been one o f the m ost valuable B ritish ex p orts since the begin n in g o f the electrical industry. In no o th e r manufactured p ro d u ct is su p rem e B ritish quality m ore carefully and th o ro u g h ly assured by contin u ou s research into materials and processes.

T h e A n c h o r C a b le C o . Ltd.

B r it ish Insulated C a lle n d e r ’s C a b le s Ltd.

C o n n o lly s (B la ck le y ) Ltd.

T h e C r a ig p a r k Electric C a b le Co . Ltd.

C r o m p t o n P a rk in s o n Ltd.

(D e r b y C a b le s Ltd.) Enfield C a b le s Ltd.

E d is o n S w a n C a b le s Ltd.

(T h e E diso n S w a n Ele c tric Co . Ltd.) W . T . G lo v e r & C o . Ltd.

G re e n ga te & Irw ell Ru b b e r C o . Ltd.

W . T H e n le y ’s T e le grap h W o r k s C o . Ltd.

T h e In d ia -R u b b e r, G u tta - P erch a & T e le grap h W o r k s C o . Ltd.

(T h e S ilv e rto w n C o .) Johnson & P h illip s Ltd.

L iv e rp o o l Electric C a b le C o . Ltd.

Th e L o n d o n Ele c tric W ir e C o . and S m ith s Ltd.

T h e M a c in to sh

C a b le C o . Ltd.

T h e M e t r o p o lita n Ele c tric C a b le & C o n s tru c tio n

C o . Ltd.

P ire lli-G e n e ra l C a b le W o r k s Ltd. (G e n e ra l

E le c tric C o . Ltd.) St. H e le n s C a b le

& Ru b b e r C o . Ltd.

S ie m e n s B ro th e rs & Co.

Ltd. (S ie m e n s E lectric L a m p s and Su pplies Ltd.) S ta n d a rd T e lepho nes

& C a b le s Ltd.

U n io n C a b le C o . L td .

C A B L E M A K E R S A S S ⁰ C 1 A T 11 0 N

H I G H H O L B O R N H O U S E • 52-54 H I G H H O L B O R N . L O N D O N • w.c.i

3 OCTOBER 1947 THE E L EC T R IC IA N

B

I t g i v e s

T his therm om eter pointer indicates the use which can be made of the unusual expansion character­

istics o f nickel-iron alloys. I t is actuated by bimetallic strip in which both the low and high expansion elements are usually nickel- iron alloys. T here is available for the electrical industry a range of alloys possessing good mechanical properties and giving co-efficients o f expansion between o and 21 millionths per °C.

O ur Development and Research D epartm ent will be pleased to give advise on expansion control problems.

a n

The Mond Nickel

4A/M/2

Company, Ltd.

C ro sv e n o r H o u se , P a rk Lane, London, W .l.

For fallability Specify

COPPER CONDUCTORS

r/m

To-day, more than ever, materials used in electrical industry must be accurate and reliable to the highest degree. This is especially true of conductors, where tensile, ductility, gauge and conductivity must conform to the most exacting specifications. Our products are distributed throughout the world. Let us quote for your require­

ments. Our skilled stall [I is at your disposal. ||H

A Y L O R 12 IS

THE E L E C T R IC IA N 3 OCTOBER 1947

I T H E M A R C H OF L I G H T

A nciew t Britons to go

to btd by

tomyk L ight. . .

t o d a y t h e r e ’s

the wonderful lamp

„ S.& .C.

PR O DU CT I A d v t . o f T h e G e n e ra l E le c tric Co. L td ., M a g n e t H o u se , K in g sw a y L o n d o n W .C .2 . I

n T H E e l e c t r i c i a n

3 OCTOBER 1947

N O . 7 O F T H E ( Q

^a

T | M ) D I T T I E S

m m ost unpleasant bloke from Fife, Lies m u rdered w ith a carving knife : Just skew ered to the library floor, S u rro u n d e d by a pool o f gore.

The gre at detective, frow n in g, views T he spot m arked X in search o f clues.

A h ! w hat are these small objects here ? S ix o f a kind, th a t’s v e ry clear.

H e studies them w ith puzzled brow , Then cries “ T he case is clearer n o w __

T h e ir perfect u niform ity

S h ow s th e y ’re tu rn ed parts from D & T !

! S ^

TIM M INS I?

Head Office : B IL L E T R D „ W A L T H A M S T O W

, L O N D O N , E. 17

Phone: Lark sw ood 2313 (6 lines

D O R M A N & S M I T H LTD. M A N C H E S T E R • L O N D O N • G L A S G O W

O rir B oar*™

O p e n m a r in e .ty p e sw itc h b o a r d co n tr o llin g th r ee 200 k W g e n e r a to r s a n d cir c u its a n d in c o r p o r a tin g D orm an XL air- b r e a k c ir c u it b r e a k e r s an d D orm an " F " ty p e s w itc h e s a s in sta lle d o n th e L.N.E. R a ilw a y 's n e w c a r g o lin e r S.S. A rnhem

(John B row n & C o., Ltd.)

THE E L E C T R IC IA N

E 2 I4 7

3 OCTOBER i 947

977

THE LONDON ELECTRIC WIRE COMPANY AND SM IT H S LIMITED, LEYTON, LONDON, E.10

3 OCTOBER 1947 THE E L EC T R IC IA N

W ALTER CRANE

REPAIRS AND REWINDS

W e specialise in the re-w inding of all types of electrical equipm ent including portable tools, vacuum cleaners, etc.

Trade List on application.

W A L T E R C R A N E , G reencoat W o r k s, W akefield.

VULCANIZED FIBRE.

E B O N IT E , B A K E L IT E

l h « M i , Rod«, T u b e s a n d M a o h ln e d S h a p a a

L E A T H E R O ID Sheet«, Roll«, etc.

“ C L IF T E X ” Insulating Tapes.

Insulating Staples, Jointing, Presspahn.

MOSSES & MITCHELL LTD.

60-68, Ironm on ger Row, London, E.C.1.

For accurate

f p f a f

oven temperature,

7 y ]

measurement and

control

f y t o t h e r m

R E W I N D S

A .C . and D .C . 1-500 h.p.

Manufacturers of Armature and Stator Coils, Commutators, etc.

R E C O N D I T I O N E D

A C . and D .C . M O T O R S , G E N E R A T O R S , S W IT C H - G E A R , etc., etc., etc.

O L D F I E L D

E N G IN E E R I N G C O ., LTD., 96, East O rd sall Lane, S A L F O R D , 5.

’G ram s: Stalwart, Manchester.

Phone: B L A 3842 and 3.

T H E B R IT IS H R O T O T H E R M Co., Ltd.

M E R T O N A B B E Y , S . W .1 9. L ib e r t y 3406.

a n d a t 87, S t . V in c e n t S t , G la s g o w , C.2.

THE E L E C T R IC IA N 3 OCTOBER 1947

979

measuring instrument. Fully descriptive pamphlet available on application to the Sole Proprietors and Manufacturers

THE A U T O M A T I C COIL WI N D E R & E L E CT R I C A L E Q U I P M E N T C O. , LT D.

W I N D E R H O U S E • D O U G L A S S T R E E T • L O N D O N - S - W - I T E L E P H O N E . V IC T O R IA 3 4 0 4 / 9

3 OCTOBER 1947 THE E L EC T R IC IA N

2 VALUE LI NES

4 ' 0 ' 40w. “ C om pendium ” co m - p rising :—

1 P ow er F a c to re d C hoke ; 1 S ta r te r L a m p a n d H o ld e r ; 2 B i-p in T u b e H o ld ers ; 1 B i-pin F lu o resce n t Tube.

C O M P L E T E S E T S O F A U X IL IA R Y G E A R A N D F L U O R E S C E N T L A M P S F O R 4 8 "

40w . L A M P A N D 3 6 " 30w . L A M P W rite for fu ll d e ta ils and fo r our

ntest 2 0 -p a g e illu stra te d c atalogu e

S C E M C O L T D . ,

fi & 7 SOHO ST., LONDON, W . l . G E R . 1461-2-3.

3 6 " 30w . “ C om pendium "

com prising 1 C h o k e ;

1 P ow er F a c to r C o n d en so r;

1 R ad io S u p pressor C o n d en so r;

1 S ta rte r L am p ; 2 B .C. L am p H old ers ; 1 36" F luorescen t Tube.

DO § C S DDAPIH!RA<GM§

EÜJEMÆNT S T R O P S C C O N D E N S E R P L A T E S

S T O V E P A N E L S ' R A W MOCA W A S H E R S

etc

M I C A C ° LT-D ^ -B E D F O R D .

Modern Lighting calls

To take full advantage of the high efficiency of F lu o re sc e n t and G a s - e o u s-d isc h arg e lighting it is necessary to correct the pow er factor of these lamps. D U B I L I E R N I T R O G O L C A P A C IT O R S are the most effective, reliable and convenient method of ensuring this correction. The N I T R O G O L process means small, light and dependable Capacitors easily placed in position in all standard fittings. C om plete suppressor units are also available in a wide and com prehensive range.

Full technical details on request.

D U B IL IE R C O N D E N S E R C O . (1925) LTD., D U C O N W O R K S , V IC T O R I A R O A D , N O R T H A C T O N , L O N D O N , W .3.

Telephones: A c o rn 2241 (5 lines).

Telegrams: H ivoltcon, Phone, London.

Cables: Hivoltcon, London. M arconi International Code.

THE E L EC T R IC IA N 3 OCTOBER 1947

981

L o -V o -L ite

TRANSFORMER SWITCH-FUSE

UNIT

F O R S A F E & E C O N O M IC A L L O C A L I S E D L I G H T I N G

In the p ro d u ct of the Specialist there are d e ta ils of design that distinguish it from its contemporaries.

C O M P L E T E L Y S E L F -IS O L A T IN G

T R A N S F O R M E R

©

V A C U U M

IM P R E G N A T E D T R A N S F O R M E R G IV IN G H IG H P R IM A R Y

T O S E C O N D A R Y IN S U L A T IO N

©

D O U B L E P O L E FU SES ( A N D SP A R E S) F O R B O T H W I N D I N G S

©

S E C O N D A R Y FU SE H O L D E R O F L O W R E S IS T A N C E C O N T A C T S E N S U R IN G

L O W V O L T A G E D R O P O N S E C O N D A R Y

R E C E S S E D S W IT C H P R E V E N T S S H O P B R E A K A G E S

U N IV E R S A L B A SE F O R E IT H E R M A C H IN E , B E N C H O R T R A N S F O R M E R

M O U N T IN G

(A SK FOR PUBLICATIO N 68610)

L O N D O N • B I R M I N G H A M • B R IS T O L • C A R D IF F • G L A S G O W • L E E D S • M A N C H E S T E R • N E W C A S T L E • S H E F F IE L D

3 O C T O B E R 1947 T H E E L E C T R IC IA N

" S T U R D Y "

TRANSFORMERS

FOR POW ER & LIGHTING DISTRIBUTION 2 0v a t o 2 0k v a.

S I N G L E P H A S E . T H R E E P H A S E S C O T T C O N N E C T E D . T H R E E T O O N E P H A S E . D O U B L E

;O R A U T O W O U N D

H I G H - R E A C T A N C E T Y P E F O R D I S C H A R G E T U B E . N E O N L IG H T IN G . S U N R A Y L A M P S

W E L D I N G T R A N S F O R M E R S

R A D I O M A I N S T R A N S F O R M E R S & C H O K E S T O S P E C IF IC R E Q U IR E M E N T S

C H O K E S F O R M .V . D I S C H A R G E L A M P S C O I L W I N D I N G T O S P E C I F I C A T I O N

Q U O T A T I O N S B Y R E T U R N

R E W I N D S . A L L M A K E S O F R A D I O - T R A N S F O R M E R

N o rm a l Delivery 7 days

STURDY ELECTRIC CO. LTD.

D IP T O N (Tel. Dipton 221) N E W C A S T L E - O N - T Y N E .

COMPLETE OVERHAULS R E W IN D IN G

A N D

Q U I C K D E L I V E R Y

ELECTRICAL CO. LTD.

4I2-414, C A L E D O N I A N R O A D . IS L IN G T O N . L O N D O N , N.7.

Telephone: N O R T H 4871-2

À C D I R E C T S W I T C H I N G C O N T A C T O R S T A R T E R S

T yp e A . 30 Size one, for starting S q u irre l C age M o t o rs up to 7 % h.p.

Provided w ith undervoltage release and three hand re­

setting overcurrent releases andenclosed indust-protectlng case. Supplied w ith push­

buttons in lid o r for remote operation.

D O N O V A N S

T H E D O N O V A N E L E C T R I C A L C 9 LT.° B IR M IN G H A M , 9 E L E C T R I C A L E N G IN E E R S AND S T O C K H O L D E R S . A « e * e -S T E C H i0 R 0 2 2 7 7 (P.B.X.) S/m m s-DONOVAN.Bium.ngm.k»'

THE E L E C T R IC IA N 3 OCTOBER 1947

983

< ) /v iM ila te c l

W I R E S

A N D C A B L E S

INSTRUMENT WIRES : STRANDS & BRAIDS TELEPHONE & RADIO CORDS & CABLES

RESISTANCE WIRES : GLASS COVERED CONDUCTORS P.V.C. TUBINGS

f o r *

Elextt/iical Co Ltd

A L P E R T O N - W E M B L E Y - M I D D L E S E X

T E L E P H O N E I P E R I V A L E 5 6 2 1 - 2 T E L E G R A M S ’. E N G I N EYOR, P H O N E , L O N D O N

j OCTOBER 1947 THE E L EC T R IC IA N

M ffs ilo jp h o d o it io iii

Hypsilophodon fox!

This prehistoric creature was the smallest of the Dinosaurs, being about four or five feet long. It walked on its hind legs, and climbed trees in search of young leaves and buds which were its favourite food.

Hypsilophodon, which was found in the Isle of W ight, shows characters which makes it one of the most Interesting of the Dinosaurs.

but it s e a s ie r to s a y

E N F I E L D

for all Cables up to 132 kV

P A P E R • R U B B E R • P. V . C .

E N F I E L D C A B L E S L I M I T E D . B R I M S D O W N , M I D D L E S E X

W o r k s : Telephone: H O W ar<* 2661 London Offices: Telephone: H O L b o r n 0591

THE E LEC T R IC IA N 3 OCTOBER 1947

T H E

E L E C T R I C

E S T A B L I S H E D 1 8 6 1

Bouverie House - 154 Fleet Street - London E C 4 Telegrams-, “ b e n b r o tr ic f l e e t London” Telephone: c e n t r a l 3212(16 lines) E ditor: S ta n le y G. R a tt e r , A .M .I.E.E. Publisher a nd M anager: J o h n V estey N um ber 3616 3 O C T O B E R 1947 Vol C X X X I X N o . 14

C O N T E N T S

Views on Current A ffairs ... 985 Im pression of R adiolym pia ... ... 988 S t. Paneras E lectricity Jubilee ... 991 D iscovery of th e E lectron ... 992 The I .E .E . and the E lectron ... 993 The E lectron in In d u s tr y ... 995 P ortrait—Mr. D. B. H oseason ... 997 A b o u t Transform ers ... 998 B a tti-W a lla h s’ Society ... 1001 Electrical Personalities ... 1002 Business E fficiency E x h ib itio n ... 1003 C ontracts Open ... 1004 E .D .A . Area Conferences ... 1005 E lectricity S u p p ly ... 1007 In d u stria l In fo rm a tio n ... 1009 L a m p Sales P u b licity ... 1012 C om pany N ew s: Metal Prices ... 1013 Commercial In fo rm a tio n : Coming

E v e n ts ... 1014

M I D L A N D S O F F I C E :

D aim ler House, Paradise Street, Birm ingham Telephone : M id la n d s 0784— 5

S C O T T I S H O F F I C E : 116, H o p e Street, Glasgow, C.2 Telephone: Central 3970

The offices o f T h e E l e c t r i c i a n are closed on S a tu rd a ys in accordance with the “ Five-day W e e k" plan adopted by B enn Brothers, Ltd.

S I N G L E C O P Y (Fr i d a y) (BY POST) A N N U A L S U B S C R I P T I O N H O M E A N D O V E R S E A S

6d.

8^d.

30s.

Winter Prospects

T

H E o p in io n o fte n ex p ressed in th e s e co lu m n s, t h a t th e e le c tric ity su p p ly p o s itio n in th e com ing w in te r m a y be a s serious, if n o t w orse, th a n la s t, w ere c o n ­ firm e d w h e n Sir G u y N o t t - B o w b r ,

d e p u ty se c re ta ry of th e M in istry of F u el, re v e a le d to a P re s s co n feren ce la s t w eek t h a t th e a n tic ip a te d g a p b e tw e e n a v a il­

ab le g e n e ra tin g c a p a c ity a n d e s tim a te d d e m a n d w ill b e g re a te r, b y 500 000 k W , th a n in th e c o ld e s t d a y s o f la s t w in ter.

I n th e w eek b efo re th e J a n u a r y coal crisis b ro u g h t in d u s tr y 'to a c o m p a ra tiv e s ta n d ­ still, m a x im u m . d e m a n d w a s ru n n in g a t a b o u t 11 000 M W , w ith 9 000 MW of plant- a v a ila b le to m e e t it. B y n e x t C h ristm a s, th e a v a ila b le c a p a c ity o n th e g rid will, i t is expected!, h a v e increased!

to 9 500 M W , b u t a g a in s t th is, d e m a n d is e x p e c te d to rise to 12 000 M W , le a v in g a n e s tim a te d deficiency o f 2 500 M W , c o m p a re d w ith 2 000 M W l a s t w in te r.

T h e to ta l in s ta lle d c a p a c ity w ill b e som e­

th in g ov er 12 000 M W , of w h ic h b e tw e e n 13 a n d 14 p e r c e n t, w ill b e n o n -a v a ila b le fo r v a rio u s reaso n s, a m o n g w h ic h o v e r­

age p la n t a n d 'the effect of p o o r q u a lity coal su p p lie s m u s t r a n k high.

A lm o st e q u a lly d is tu rb in g is th e s itu a ­ tio n re g a rd in g coal stocks. B asin g figures o n a n e s tim a te d w eek ly w in te r c o n su m p tio n of 700 000 to n s , th e M inis­

t r y la s t w eek a n n o u n c e d t h a t sto c k s a t p o w er s ta tio n s n ow s ta n d a t b e tw e e n five a n d six w eek s’ su p p ly . T h is is a n im p ro v e m e n t o n th e s itu a tio n e x istin g a t th e sam e tim e la s t y e a r, w h e n a b o u t th r e e w eek s’ sto c k w ere h eld , b u t, as if to e n d o rse th e s t a te m e n t m a d e in th e se n o te s a fortnight- ago, th e M in istry of

D

F u e l a g re e s t h a t th e r e is li ttle c h a n c e of t h e “ s a f e ty le v e l ” of e ig h t w eek s’ s u p ­ p ly b e in g reached', a n d t h a t th e r e is still a d a n g e r, if t h e w e a th e r sh o u ld b e u n ­ d u ly sev ere, o f y e t a n o th e r co al crisis b e fo re th e e n d of w in te r. “ W e h o p e ,”

w a s a ll Sir ^{G u y} w o u ld sa y , “ t h a t w ith th e c o -o p e ra tio n of c o n su m e rs a n d w ith ­ o u t a b n o rm a lly b a d lu c k w e sh a ll b e a b le t o g e t th r o u g h .” T h is official a d m issio n is, in fa c t, t h e o n ly r e s p e c t in w hich th e s itu a tio n m a y b e s a id to b e b e t t e r th a n la s t y e a r, w h e n a c o m p le te ly u n w a r r a n t­

a b le o p tim ism w a s b e in g d is p la y e d b y M in iste r a n d official s p o k e s m e n alike.

P ro b lem o f D o m e stic Load N E X T w eek, t h e p la n s fo r in d u s tria l lo a d s ta g g e rin g a r e t o b e c o m e o p e ra tiv e a ll o v e r t h e c o u n tr y , a n d fo r a v a r ie ty o f re a so n s, in c lu d in g t h e a t t i t u d e of so m e s e c tio n s o f o rg a n ise d la b o u r t o sh ift- w o rk in g h o u rs , i t is a p p a r e n t t h a t fa r f r o m t h e o rig in a l t a r g e t of a o n e -th ird s p r e a d in lo a d b e in g m e t, a r e d u c tio n of a b o u t 2 0 to 26 p e r c e n t, is a ll t h a t can b e e x p e c te d . T h e re is, th e re fo re , n o re a s o n t o su p p o s e t h a t th e fo re c a s t of t h e M in is try of F u e l t h a t “ i t is q u ite p o ssib le t h a t w e s h a ll b e b r o u g h t u p a g a in s t h e a v y lo a d sh e d d in g if i t is a co ld w in te r ,” is in a n y w a y o v e r-p e ssi­

m istic . O ne of th e p ro b le m s seek in g s o lu tio n is h o w t o m e e t th e d e m a n d of t h e d o m e s tic c o n su m er, w h o se c o n s u m p ­ tio n h a s in c re a se d fro m 6000 m illio n u n its p e r a n n u m in 1938 t o 12 000 m illio n in th e c u r r e n t y e a r. D u rin g th e su m m e r th e G o v e rn m e n t a g a in c o n sid e re d th e w a r-tim e r a tio n in g p ro p o sa ls, o n ly to d ism iss th e m o n t h e g ro u n d t h a t th e y w o u ld , a m o n g o th e r tilin g s, fa ll in e q u it­

a b ly o n th o s e c o n su m e rs w h o h a v e a l­

r e a d y re d u c e d th e ir d e m a n d to a m in i­

m u m . T h e e x p e d ie n t o f “ p ric e d is in ­ c e n tiv e s ,” in th e fo rm of a d is c o u ra g in g ly la rg e in c re a se in c o s t p e r u n it, w as, q u ite rig h tly , a lso re je c te d . I f th e d o m estic lo a d is t o b e re d u c e d , th e re fo re , th e r e re m a in s b u t o n e a lte r n a tiv e , t h a t of -v o lu n ta ry e c o n o m y . A c a m p a ig n to

t h a t e n d is n o w u n d e r w ay .

L ocal Fuel S avin g C om m ittees T H E c u r r e n t d o m e s tic e c o n o m y c a m ­ p a ig n is d is tin g u is h e d fro m its p re d e ­ cesso rs b y b e in g o n a lo cal b asis. C om ­ p risin g in m o s t cases re p r e s e n ta tiv e s of

t h e lo c a l m u n ic ip a lity , th e lo cal gas a n d e le c tric ity u n d e rta k in g s , w o m e n ’s o rg a n is a tio n s a n d o th e r lo c a l bodies, fu e l sa v in g s c o m m itte e s a re b e in g e s t a b ­ lish e d in to w n s a n d c itie s th r o u g h o u t th e c o u n tr y . D e le g a te s fro m th e s e co m ­ m itte e s w ill in th e c o u rse o f th e n e x t few w eek s a t t e n d m e e tin g s to b e h e ld in th e m a jo r ity of th e la rg e r to w n s, w h e re ithey w ill h e a d d re s s e d b y a M in ister, a n d w h e re th e y w ill d iscu ss w a y s a n d m e a n s of im p re ss­

in g t h e g r a v ity o f t h e s itu a tio n o n co n su m e rs in th e ir localities. T h e g e n e ra l p u b lic , w h ic h h a s b e e n e x h o rte d to sa v e o r eco n o m ise in on e d ire c tio n o r a n o th e r sin ce 1939, is n o w u n d e r s ta n d ­ a b ly sh o w in g a n a p p re c ia b le im m u n ity to n a tio n a l c a m p a ig n s, a n d i t m a y b e t h a t u sefu l re s u lts .will em erg e fro m th e d ecisio n to p la c e t h e ta s k of p u b lic e d u ­ c a tio n o n th o s e w ho k n o w , a n d a re k n o w n b y , th e ir ow n to w n sp e o p le . T he F.B.I. and Pow er Stations I N a l e t t e r to “ T h e T im e s ” l a s t w eek S ir N o r m a n Ki p p i n g, D ire c to r-G e n e ra l o f t h e F .B .I., a sk e d w h e th e r th e r e w as a n y lik elih o o d , in v iew o f th e in d u s tria l r e ­ o rg a n is a tio n a n d d e fe rm e n t of re - e q u ip ­ m e n t w h ic h th e e x p o r t d riv e w ill e n ta il, o f t h e g ro w th in d e m a n d fo r elec tric p o w e r k e e p in g p a c e w ith th e

£450 000 000 e x te n s io n p ro g ra m m e a n ­ n o u n c e d r e c e n tly b y th e C .E .B . I n ­ c id e n ta lly , h e inquired', w h a t p ro p o r tio n o f t h e c u r r e n t g ro w th in d e m a n d w o u ld d is a p p e a r if th e r e w ere n o s h o r ta g e of solid fu e l? S ir N Or m a n's m isg iv in g s a re u n d e rs ta n d a b le , b u t th e r e is little re a s o n to su p p o s e t h a t t h e C e n tra l B o a r d ’s e s tim a te s w ill p ro v e excessive, if th e b a la n c e of tr a d e p o s itio n is to b e a p p re c ia b ly im p ro v e d . O f th e 10 000 M W of n e w p la n t, 2 500 M W is n e e d e d to close th e e x is tin g g a p b e tw e e n d e m a n d a n d a v a ila b le su p p ly , a n d a la rg e p a r t w ill go, n o t to in c re a se th e n a tio n a l c a p a c ity , b u t to re p la c e th e g ro w in g p ro p o r tio n o f e x is tin g g e n e ra tin g e q u ip m e n t w h ic h is o v er-ag e a n d c o n se­

q u e n tly inefficient. F u r t h e r , a lth o u g h t h e c o n te m p la te d econom ies in c a p ita l e x p e n d itu r e m a y p r e v e n t m a n y in d u s trie s fro m c a rr y in g o u t n e w p ro g ra m m e s o f e le c trific a tio n in th e n e a r fu tu re —i n tim e th e y w ill b e fo rc e d to d o so— in d u s tria l d e m a n d a s a w hole w ill o b v io u sly k e e p in s te p w ith risin g p ro d u c tio n , a n d th e

THE E L E C T R IC IA N 3 OCTOBER 1943

987 p la n s fo r a g ric u ltu re , w ith th e ir e m ­

p h a s is on d a iry -fa rm in g , w ill re s u lt in a h e a v ie r r u r a l load. T o Sir Norman’s

l a s t q u e stio n , tw o an sw ers su g g e st th e m ­ selves. F ir s t, t h a t th e e n d of t h e coal s h o rta g e fo r d o m estic c o n su m e rs a p p e a rs to b e se v e ra l y e a rs off; seco n d , t h a t t h e re c o rd of th e d o m estic lo a d in p re ­ w a r y e a rs , w h e n co al w as b o th ch e a p e r a n d a b u n d a n t, w a s on e of c o n tin u o u s g ro w th .

The E lectron Jubilee D iscourse H IM S E L F a b r ill ia n t e x p o n e n t of th e a r t o f p u b lic d e m o n s tra tio n , J . ,T.

Th o m so n w o u ld h a v e w holly a p p ro v e d of th e m a s te r ly e x p e rim e n ta l d isco u rse o n “ T h e E le c tro n L ib e r a te d ” d eliv ered in h is h o n o u r b y Sir Cl if f o r d Pater­

so n, F .R .S ., a t th e C e n tra l H all, W e s tm in s te r, l a s t w eek. W ith th e polish of a first-c la ss c o n ju ro r, s u p p o r te d b y th e a u th o r it y of a d is tin g u ish e d scien tist, S ir Cl if f o r d g a v e a n e n te r ta in in g a n d in s tr u c tiv e a d d re s s w h ic h w a s follow ed w ith r a p t a tte n ti o n e q u a lly b y a p a r ty of sch o o l-ch ild ren in th e g a lle ry a n d a g ro u p o f n o ta b le e le c tric a l en g in ee rs in th e f r o n t row . I n th e co u rse of a n h o u r, h e to u c h e d o n n e a rly e v e ry im p o r t a n t a s p e c t of m o d e rn elec tro n ics, illu s tra tin g e a c h p o in t b y d e m o n s tra tio n s , th e tim ­ ing a n d su ccess of w h ic h c a n on ly b e a p p re c ia te d b y th o s e w h o h a v e th e m ­ selv es e x p e rie n c e d t h e u n w illin g n ess of co m p lex d ev ice s to b e h a v e s a tis fa c to rily b efo re a n au d ie n c e . T h e d e liv e ry of th e a d d re s s its e lf w a s p ro b a b ly th e le a s t s tre n u o u s p a r t of th e ta s k , w h ic h m u s t h a v e b e g u n , in th e p r e p a r a tio n of s c r ip t a n d b u ild in g of a p p a r a t u s , m a n y w eeks before. A t th e C e n tra l H a ll, t h e a p p re ­ c ia tio n of th i s w o rk b y th e au d ien c e w as u n m is ta k e a b le , a n d w ell deserv ed . R ad iolym pia

A F I T T I N G tr i b u t e to th e w o rk off J . J . Th o m so n is to be seen a t th e R a d io E x h ib itio n a t O lym pia, w h ich o p e n e d fo r te n d a y s o n W e d n e sd a y . T h e tr ib u te is a ll th e m o re im p re ss iv e fo r—

in n o w a y in te n d e d to coincide w ith th e e le c tro n ju b ilee— i t sh o w s th e l a t e s t d e v e lo p m e n ts in th e e lec tro n ic field, b o th w ith r e s p e c t to th e b ro a d c a s tin g of so u n d a n d te le v isio n a n d th e a p p li­

c a tio n of elec tro n ics t o in d u s try . M an y o f th e a p p lic a tio n s to w h ic h D r.

Al l ibOne re f e rre d a t th e I .E .E . m e e t­

in g l a s t w eek, m a y b e seen in o p e ra tio n o r in s p e c te d , a n d if a n y co n firm a tio n w a s n e e d e d of- o u r claim la s t w eek t h a t i t is u p o n t h e d isco v ery of 1897 t h a t m o d e rn -d a y e le c tro n ic e n g in ee rin g is fo u n d e d , i t is in ev id en c e th i s w eek a t th e O ly m p ia show .

M isuse o f M em b ersh ip Initials T H E C ouncil o f th e I n s tit u ti o n of E le c ­ tr ic a l E n g in e e rs a r e d e e p ly c o n c e rn e d a t th e in c r e a s e in r e c e n t m o n th s of cases o f t h e w ro n g fu l u se of in itia ls in d ic a tiv e of m e m b e rsh ip o f th e in s titu tio n , b y p e rs o n s w ho a r e n o t e n title d to u s e th e m . O u r a tt e n ti o n h a s b e e n d ra w n to th e f a c t t h a t th e C ouncil a r e p re s e rv in g th e ir cusitom ary v ig ilan ce in th e s e m a tte r s , a n d in t h e g e n e ra l , in t e r e s t of th e p u b lic a n d of th e p ro fe ssio n a r e m a k in g e n e rg e tic u se of all p ro p e r m e a s u re s w h ic h m a y b e o p e n to th e m to s to p th e p r a c tic e ; in p a r t ic u l a r to o b ta in s a tis f a c to r y u n d e rta k in g s fro m o ffen d ers t h a t th e y w ill r e f r a in fro m f u r th e r offence. W h e re §uch a n u n d e r ­ ta k in g h a s n o t b e e n fo rth c o m in g , th e C ouncil h a v e h it h e r t o n o t h e s ita te d to ta k e p ro c e e d in g s in th e H ig h C o u rt fo r a n O rd e r of th e C o u rt c allin g u p o n th e offen d er to a b a n d o n t h e u se of t h e in itia ls a n d to d e liv e r u p fo r d e s tru c tio n a n y s ta tio n a r y o r o th e r p r in te d m a t te r e x h ib itin g a w ro n g fu l u se of in itia ls , a n d th e y in te n d to c o n tin u e th is policy.

M eanw hile, e m p lo y e rs sh o u ld , in th e ir ow n in te re s t, w h en in te rv ie w in g p ro s ­ p e c tiv e em ployees, ca re fu lly ch eck a n y claim s to I .E .E . m e m b e rsh ip .

B usin ess Efficiency

T H E firs t B u sin e s s E fficiency E x h ib i­

ti o n to b e h eld since th e w ar, w as o p e n e d a t O lym pia o n W e d n e sd a y , a n d th o u g h i t does n o t re v e a l a n y th in g s trik in g ly new in office m a c h in e s a n d sy ste m s, th e r e w ill b e n o te d a sig n ific a n t c h a n g e in e m p h a s is in a p p lic a tio n , a s a re s u lt of th e w a r. T h e e x h ib itio n is b e in g h e ld b e c a u se of it s e d u c a tio n a l v a lu e in d e m o n s tr a tin g t h e s tr id e s m a d e in office e q u ip m e n t since p re -w a r a n d i t show s also th e in creasin g ly im p o r ta n t p a r t w h ich e le c tric ity p la y s in th e efficient- ru n n in g of c o m m ercial u n d e r ta k in g s ; a p a r t in th e d e v e lo p m e n t of w h ic h t h e su p p ly in d u s tr y m ig h t claim to h a v e sh a re d v e ry a p p re c ia b ly .

5 OCTOBER 1947 THE E LEC T R IC IA N

Impression of Radiolympia

E xam ples o f Progress S in ce the 1939 E xhibition

T

H E first po st-w ar N atio n al R adio E x h ib itio n , organised b y th e R adio I n d u s tr y Council, was opened on W ed­

n esd ay a t O lym pia, a n d will rem ain open u n til O ctober I I .

I n th e eig h t y ears since th e la s t R adiolym pia, w ar-tim e research on ra d a r a n d rad io com m unication h a s led to im­

p o rta n t advances in th e u ltra-h ig h fre ­ qu en cy field, in servo control m echanism s an d in th e design of com ponents. T he m ain in te re s t in th e p re s e n t exhibition lies, th erefore, in a s tu d y of th e effects of these developm ents on th e p roducts shown. W hile th e circu its of the average dom estic receiver show little rad ical d e p a rtu re from those of pre-w ar day s, th e m in ia tu risa tio n of com ponents an d th e use of new m a te ria ls is m uch in evidence, a n d in th e m a n y television receivers displayed, a d v a n ta g e h a s been ta k e n of th e progress m ad e in th e design of scanning circu its a n d cath o d e -ray tubes.

EMERGENCE OF ELECTRONICS Possibly th e m o st strik in g distinction betw een th e exhibition a n d its predecessors is th e em ergence of “ elec­

tronics ” as a n in d u s tria l tech n iq u e of con­

siderable im p o rtan ce. T his is a p p a re n t on th e sta n d s of th e m a jo rity of th e larger m a n u fa c tu re rs w here are show n exam ples of in d u stria l controllers, radio-frequency h e a te rs an d various specialised in s tru ­ m en ts, all owing m u ch to w ar research.

A n o th er new com er is ra d a r, an d on several sta n d s th ere are in s tru m e n ts developed from a p p a ra tu s designed for th e Services an d now com ing in to increasing use for sea a n d air navigation.

O ne of th e first r a d a r sets to he com­

m ercially developed is th e M etropolitan- V ickers “ Seascan ” eq u ip m en t, a cen tri­

m etric s e t of th e P .P .I . ty p e w hich w as recen tly in stalled on th e “ Q ueen M ary.'”

W ith fo u r ranges, th is se t can d e te c t o b jects u p to a m ax im u m ra n g e of 30 m iles a n d , ;by v irtu e of a v ery sh o rt tra n s m itte d pulse, give clea r indications dow n to 50 y ard s. T h e sam e com pany is also showing new rad io an d te s tin g a p p a ra ­ tu s. T hese include a low -pow ered m ark er b eacon fo r use o n airfields, a p o rtab le signal g en erato r, a “ m id g et ” cathode- ra y oscilloscope a n d an electronically- stabilised pow er u n it.

A ssociated w ith ra d a r is a new p ro d u ct d e m o n s tra te d b y F e rra n ti, L td ., b y m eans of a w orking m odel. I t is k now n as th e hyperbolic n av ig atio n al co m p u ter, a n d has

(been designed to con v ert au to m atically the info rm atio n o b tain ed by ra d a r navigational system s in to term s of range a n d bearing.

Two in d u strial p ro d u cts show n are a y a rd b re a k a g e d e te c to r an d a n electronic cloth guiding device, b o th recen tly developed for th e textile in d u s try . O n th e sta n d a re also some specially designed lam ps a n d valves a n d a te s t in stru m e n t, know n as th e “ T esv ac,” w hich is a portab le source of high freq u en cy energy fo r d e te c t­

ing air leaks in e v acu ated envelopes.

M arine ra d a r is also fe a tu re d on the s ta n d of th e B ritish T hom son-H ouston Go., L td ., th is tim e in th e form of a p ro to ty p e e q u ip m en t developed for m e rch an t ships a n d a lre a d y being te s te d on a n u m b er of vessels. A m icro-w ave d etec to r of m oving o b jects is u sed to d em o n strate th e p rin ­

ciples on w hich th e p ro x im ity fuse was designed. .Other dem o n stratio n s show an electronic-am plidyne position-control seryo m echanism a n d a th y ratro n -co n tro lled m o to r in operation. In d u s tria l e q u ip ­ m e n t m ad e b y th e com pany is rep resen ted toy a new resistance w elding control panel, a hig h frequency h e a te r, a photo-cell relay a n d a v a rie ty of specialised valves.

W ith fo u r stan d s in th e exhibition, th e E..M .I. gro u p are show ing one of th e ir w a r­

tim e ra d a r , developm ents, “ R eb e c c a ,”

w hich is now becom ing a w idely used fittin g fo r guiding a irc ra ft to th e runw ay.

A n o th e r developm ent is a film scanning u n it fo r television, an d am ongst in d u strial item s are several r.f. h eate rs. O n the s ta n d of M arconi’s W ireless T elegraph Co., L td ., a m arine ra d a r on w hich th e p ictu re received on th e P .P .I . screen m a y be com pared in sta n tly w ith th e c h a rt is show n, as well as a v a rie ty of direction­

finders a n d blind ap p ro ach guides fo r av ia ­ tio n . R e p resen tativ e exam ples of th e co m p an y ’s . broadcasting an d television tra n sm ittin g equipm ent a re also on view.

MAGNETIC SORTING BRIDGE I n a d d itio n to a 5 k W r.f. h e a te r, th e G eneral E lectric Co., L td ., show a m ag­

n etic so rtin g bridge, a device fo r keeping a continuous check on th e m echanical an d chem ical properties of ferro-m agnetic p a rts as th ey are m ade. Specim ens are ra p id ly com pared w ith a s ta n d a rd p a rt, a n y d ev iatio n of th e p ro d u c t being shown b y m eans of a sh ift on a c .r.t. tra c e . A m agnetic tap e recorder a n d a 1 kW f.m . tra n s m itte r are am ong o th e r exhibits,

A n o th e r com pany ex h ib itin g r.f. heatin g eq u ip m en t is B .I. C allender’s Cables, L td .,

THE E L E C T R IC IA N 3 OCTOBER. 194J

989

S E E N A T R A D IO L Y M P IA

This year’s radio exhibition— the 15th since the series started in 1922 and the first since the outbreak o f war interrupted the 1939 show soon after its opening— is the largest, in terms o f both stand space and the number o f exhibitors, y e t to be held. Special features include a section devoted to industrial applications o f electronics. The illustrations above, which are representative of the range o f products displayed, show : (1) the Ferranti “ Tesvac, fo r testing the vacuum tn evacuated systems ; (2) various sizes o f Dubiher “ D nhtic condensers , (3) a T.C .C . dual­

section electrolytic condenser ; (4) an electronic stabilised-voltage power unit, shown by the Metro- politan-Vickers Electrical Co., L t d .; (5) large a nd small industrial radio-frequency heaters, shown by B .I. Callender’s Cables L td. ; (6) the “ Vampire,’’ a new test set exhibited by Everett,

Edgcumbe and Co., L td.

3 OCTOBER 1947 ™ E E L E C T R 1C IA N

w hose sets include one developed fo r seam w elding of th erm o p lastic sheets a n d form s su itab le fo r soldering w ork. A n all-w ave an ti-in terferen ce a erial fo r dom estic use, w hich a c ts as a “ T ” ty p e aerial on m ed iu m a n d long w aves a n d as a tru e dipole fo r s h o rt w aves is show n, as are vario u s special w ires a n d cables.

V isitors to th e Cable a n d W ireless sta n d are able to see in o p eratio n a w orking w ireless-telegraph circuit relay in g to the co m p an y ’s sta tio n a t B arb ad o s, a n d a new high-speed photo-electric tr a n sm itte r, capable of 800 w ords p e r m in u te.

Two o th e r com panies show ing r.f. h e a t­

ing sets are th e M illiard W ireless Service Co., L td ., a n d P h ilip s E lectrical, L td . T h e form er display in ad d itio n , a range of silica tra n s m ittin g v alv es developed fo r in d u s tria l h e a te rs, one b ein g capable of d elivering u p to 75 k W a t 30 M c /s, a n d electronic flash tu b e s , photo-cells an d accelerom eters. O n a n in fo rm atio n stan d , v isito rs’ tech n ical q u estio n s a re answ ered, an d o n a n o th e r th e com pany h av e erected a m odel electric railw ay sy stem to dem on­

s tr a te som e of th e p ro p ertie s of p h o to ­ electric cells for in d u s tria l control, b o th of th e “ s ta rt- s to p ” v a rie ty a n d fo r dis­

crim in atin g betw een o b jects of different colours. T h ree 00 gauge tra in s ru n sim u ltan eo u sly o v er com m on track s, s ta rtin g , sto p p in g , sh u n tin g a n d building- u p th e tra in s according to th e colour of th e tru ck s is carried o u t au to m a tic a lly b y a com bination of photo-cells, valve- o p e ra te d relays a n d sequence controllers.

T he P hilips ex h ib its include m edical a p p a ra tu s , such as a m ass rad io g rap h y X - ra y u n it, a n d a 300 W short-w ave th e ra p y u n it em bodying a special ty p e o f silica v alv e. T h e in d u s tria l p ro d u cts of th e co m pany a re re p re se n te d b y a high- freq u en cy g e n e ra to r fo r h ard en in g , solder­

ing, sin terin g or m oulding m etals an d a n electronic w elding control u n it.

NEW INSTRUMENT DESIGNS In s tru m e n ts for la b o rato ry a n d factory- inspection purposes fo rm th e m ajo r item on several stan d s. S alford E lectrical In s tru m e n ts, L td ., d isp la y v ario u s moving- coil, m oving-iron a n d th erm al m eters, a resistan ce-cap acity bridge a n d a sm all e ath o d e -ra y oscilloscope, as well as q u a rtz crystals, photo-cells an d to ro id al cores a n d coils. A n in te re stin g new te s te r using a p a te n t rectifier circu it, is seen o n th e sta n d of E v e re tt E dgcum be a n d Co., L td . T h is is k now n as th e “ V a m p ire ,” an d m easures pow er in fo u r ranges u p to 5 kW , as well as c u rre n t a n d voltage.

T h ey also show a 500 V in su latio n tester, said to give a b e tte r w aveform th a n th e conventional d.c. g en erato r, a n d tw o all­

purpose te s t sets.

T h e E dison Sw an E lectric Co., L td ., dis­

p la y several specialised p ro d u cts, including th e eleetro-encephalograph an d its a sso ciate d low -frequency w ave an aly ser, shock th e ra p y eq u ip m en t a n d a n elec­

tro n ic stim u lato r. On a n o th e r sta n d , the com pany show a n office intercom m unica­

tio n system , loudspeakers, pick-ups an d v alv es a n d cath o d e -ray tu b e s . D aw e In s tru m e n ts , L td ., exhibit a sound level m e te r for d eterm in in g th e acoustic fid elity of rad io receivers, an d h a v e a special display w hich illu strates the use of stroboscopic light for lo u d sp eak er cone analysis. A useful receiver te s te r, com­

prising a crystal-checked signal g enerator, audio -freq u en cy tone source an d a n o u tp u t m eter, is show n b y M arconi In stru m e n ts, L td ., who display, in ad d itio n , a te s t bridge a n d in s tru m e n ts fo r use in receiver a n d com ponent p roduction.

HIGH TENSION METAL RECTIFIERS A new double-beam cath o d e -ray oscillo­

scope is a fe a tu re of th e S ta n d a rd Tele­

p hones an d C ables, L td ., sta n d , and several new ty p es of rectifier, including a series of ro d u n its for th e e .h .t. su p p ly of oscilloscopes a n d television receivers are show n. R ectifiers are also show n b y th e W estinghouse B rak e an d Signal Co., L td . Two of th e e .h .t. u n its displayed will, w hen em ployed in a voltage-douibler cir­

cu it, p ro v id e a n o u tp u t of 8 kV a t 8 mA.

T a y lo r E lectrical In stru m e n ts, L td ., e x h ib it m ulti-range m easuring in s tru ­ m e n ts a n d specialised eq u ip m en t such as c irc u it analysers a n d bridges, while recent ad d itio n s to th e A utom atic Coil W inder a n d E lectrical E q u ip m e n t Oo.’s range w hich m a y be seen include a n electronic te s tm e te r— a v alv e v o ltm e te r ty p e of in s tru m e n t w orking u p to 10 kV —an d th e Avo v a lv e characteristic m eter.

■Several m an u factu rers well k now n for th e ir com ponents h ave stan d s, am ong th em th e D ubilier C ondenser Co. (1925), L td ..

w ho show a com prehensive selection of c ap acito rs a n d resistors, th e la t te r includ­

ing h ig h sta b ility an d precision w ire-w ound ty p es, th e T elegraph Condenser Co., L td ..

w hose e x h ib it includes a new design of

“ M icadisc ” capacity b u sh a n d several h .t. condensers fo r tra n sm itte rs an d tele­

vision receivers, an d E lectro -th erm al E ngi­

neering, L td ., w ith a sta n d on w hich valve retain ers, resistance cords, th erm o static sw itches an d cord sw itches are to b e seen.

T he P lessey Co., L td ., show trim m ers, chokes, electrolytic condensers, switches, tran sfo rm ers a n d a n u m b e r of television coils an d o th e r com ponents.

T h e B ritish V acuum C leaner an d E n g i­

neering Co.. L td ., show, th ro u g h th e ir associate, th e M agneta Tim e Co., a rancre of p .a . am plifiers w ith o u tp u ts from 10 W to 100 W . Car radios a n d aerials an d special receivers designed fo r ex p o rt are

THE E L E C T R IC IA N 3 OCTOBER 194J

991 seen on th e s ta n d of E . K . Cole a n d Co.,

L td., in ad d itio n to th e com pany’s norm al range of dom estic receivers. T he exhibits include a large radio-gram ophone covering a w ide audio b an d .

Specialised insulating m aterials are to be seen on th e sta n d of D e L a R u e Insulation, L td ., whose p ro d u cts include lam inated boards, a la m in ated plastic m aterial in coloured sandw ich form in te n d e d fo r the engraving o f in s tru m e n t dials a n d panels a n d various decorative plastic m aterials for radio cabinets. A selection of therm o­

plastic extrusions, v ary in g in size from less th a n 1 m m . to 6 in. is show n on th e sta n d of T eneplas, L td ., th e m aterial m ainly used being P.V .C . T h e co m pany also dis­

p lay some exam ples of polythene e x tru ­ sions. A nother sta n d displaying a range of in su lated w ires is th a t of th e Sterling Cable C o., L td ., w ho are also exhibiting high-frequency coaxials. D u ra tu b e and W ire, L td ., display wires an d cables insu­

la te d w ith “ D u ra tu f S .” P .V .C ., includ­

ing screened ty p es fo r com m unications equ ip m en t. O th er applications of P.V .C.

ex h ib ited b y th is com pany are for decora­

tive strip s, carrying handles fo r p o rtab le receivers a n d th re a d fo r b inding w iring assem blies. R esistance line cords a n d the assem bly of cable form s for th e radio indus­

tr y a re show n b y R ip a u lts, L td ., o n a sta n d w hich also displays cables, wires an d in su lated a n d screened sleevings.

D om estic aerials fo r radio, television, cars, a n d a m odel from a new range de­

signed fo r frequeney-m odulation reception are show n b y A erialite, L td . T he la tte r are horizontally polarised a n d su itab ly dim ensioned to fo rm a n efficient beam . Cables e x h ib ited b y th e com pany include a coaxial feeder a n d a b alanced tw in low- loss feeder, b o th designed for television an d f.m ., u p to 1000 M c/s.

A d em o n stratio n showing how th e b it te m p e ra tu re of a soldering iron m a y be determ ined w hilst joints are being m ade is given b y M ulticore Solders, L td ., w here a special fe a tu re is a pro d u ctio n b e lt on w hich girls m ay be w atch ed assem bling a radio sub-chassis.

St. Paneras Electricity Jubilee

A

D EM O N STR A TIO N of th e effect of v arying shades of artificial light on colour in w om en’s w ear a n d th e possibilities of fluorescent lighting in decorative art, was given a t a fashion p a ra d e w hich followed a lectu re o n th is source of illu­

m in atio n , arran g ed b y T horn Electrical In d u stries, L td ., in co n ju n ctio n w ith th e S t. P an cras electricity d ep artm en t, as p a rt of th e celeb ratio n of th e 50th anniversary of th e u n d ertak in g , a t S t. P a n c ra s Town H all, L ondon, on M onday.

In tro d u c e d by Mr. A. Stanley Shier, a d irecto r o f T h o rn E lectrical Industries, L td ., w ho presided, th e M ayor said S t.

P a n c ra s w as th e first London borough to h a v e a n electricity u n d ertak in g . This was in 1891, a n d b u t for th e w ar its jubilee w ould h a v e been celebrated in 1941. Now, b ecause of presen t conditions, th e celebra­

tions were on th e au stere side an d w ould ta k e th e form of a p a rty t h a t evening for th e employees of th e u n d ertak in g . L a st w eek th e re w as an exhibition showing th e facilities t h a t were available b y th e w ay of public services. L ast y e a r th e u n d er­

tak in g generated a n d sold 98 million u n its, th e gross revenue exceeded £686 000 and, despite th e fa c t th a t concessions totalling

£6000 were m ade to consum ers, th e re was a profit of £22000.

T he lecture, in tw o p arts, on

“ F luorescent L ig h tin g ,” was delivered b y D r. J . W . S trange, chief chem ist of th e T h o rn E lectrical research laboratories, a n d D r. H . H . B allin, m anager of th e illu m in at­

ing engineering d ep artm en t.

D r. S tra n g e described th e various m ethods of sta rtin g th e electrical discharge in a fluorescent tu b e a n d in tro d u ced the

“ Q u ick start " u n it, recen tly developed b y th e com pany a n d designed fo r alm ost im m ediate s ta rtin g of th e lam p, even u n d er conditions of excessive voltage drop, as ex­

perienced la s t w inter. T he u n it consists of a n a u to -tra n sfo rm er, th e p rim ary w ind­

ing of w hich is connected across th e fluorescent tu b e , w ith th e secondary w ind­

ing in tw o sep arate sections—one across each cathode. W hen th e lam p is sw itched on, p ractically th e whole m ains voltage ap p ears across th e filam ent tran sfo rm er p rim ary a n d th e cathodes are h e a te d b y c u rre n t from th e secondary w indings. As soon as th e cathodes are h o t (th is usually tak es a b o u t half a second) th e lam p strikes a n d th e voltage across th e p rim ary of th e tran sfo rm er falls to th e lam p vo lt­

age, a b o u t 110, a n d th e cath o d e voltages are correspondingly reduced. S tartin g is assisted b y th e p ro x im ity of a n e arth ed shield inducing a n electro static field. I t is claim ed t h a t ra p id sta rtin g o f a n in stalla­

tio n designed fo r 230 V is o b tain ed a t m ains voltages below 180, an d once s ta rte d th e lam p will rem ain alight a t voltages considerably low er th a n 180; t h a t lam p life a n d efficiency are n o t reduced a n d t h a t th e a d d itio n al ru n n in g losses in tro d u ced b y th e

“ Q u ick start ” u n it are small.

D r. B allin spoke of th e application of fluorescent lam ps to store a n d domestic lighting.

3 OCTOBER 1347 THE E L E C T R IC IA N