he
World
COVERING EVERY WIRELESS INTEREST
30th Year of Publication
Proprietors : ILIFFE & SONS LTD.	No. 1055	VOL. XLVI.	No. 7
Editor		
HUGH S. POCOCK.	MA T 1940	
Editorial,		
Advertising and Publishing Office	C	t	t	
DORSET HOUSE, STAMFORD 'STREET,	n b. s	
	o n e	
LONDON, S.E.i.		
Telephone: W,,terloo 3333 (so lineel.	(	EDITORIAL CO1LME. T	235
Telegrams: " Ltha corld, Sedist, London."	"ALL-DRY" VALVES	236
COVENTRY: 8-10, Corporation Street.	VALVES AT LOW VOLTAGES.	By Z'iV. T. Cocking ..	..	239
Telegrauls :	Telephone:		
"Autocnr, Coventry."	Sao Coventry,	PROBLEM CORNER ..	..	..	241
BIRMINGHAM:	GETTING THE: REST FROM RECORDS: Part IV.—THE	
Guildhall Buildings, Navigation Street, 2.	RECORD IIAS THE LAST WORD.	By. P. G. A. H. Voigt:	
Telegrams:	Telephone:	B.Sc., A.M.I.E.E.	..	242
"Autopress, Birniingham.•"	29; r Midland (j lines).		
	MURPHY Ago:	Test Report	..	..	. •	..	..	246
MANCHESTER: 260. Deansgate, 3.	" TITE	WORLD " VALVE DATA, 1940 ; VALVE	
Tele nche :	Telephone	NWIRELESS	.	
Iliffe,	\Iauchester."	]Slack:us .14x2 (q lines).	_	• •	249
	BASE CONNECTIONS	.	
GLASGOW: 26u, Renfield Street, C.2.	VALVE SYMBOLS	256
Telegrams:	Telephone:	LETTERS TO THE EDITOR	257
Iliffe, Glasgow. •'	Central 4557.		
	NEWS Iii ENGLISH FROM ABROAD . •	..	..	..	259
PUBLISHED MONTHLY.	CURRENT TOPICS	..	..	..	..	..	260
	..	..	
Price: One Shining.		
(Publication date 20th of preceding month.)	V \.LVE, AND CIRCUIT NOISES	• •	..	..	. •	262
Subscription Rates:	-	ALL-WAVE AERIALS.	By F. R. W. Strafford	..	. •	26ti
Home and Abroad, 11- per annum.	UNBIASED.	By Free Grid ..	20
As,eanyof the circuits and apparatus described in these	RANDO1eI RADIATIONS.	By " Dlallist"	..	. •	..	271
/'ages are covered by palew.s, readers are advised, before		
making use of them, !o satisfy lttrruselve.s that they mould	RECENT INVENTIONS	273
no! be inlri;ming ˘atolls.		
I-INTEREST aiid ENTERTAINMENTThe 1it•nitations of the so-called all-wave type of receiver is tr+ost •vidant when listeni»g
in on the iiv~ly ether on 7 to 550 metres
WITH A	~` 	.:.s

ii 6 T7
Recontc:enCed raeieer in fho juu~ r eomtnunirailnne class• valve. elcabfnnt IunJsPte,dlne
ii 15 YY
new viper S.vul- A.O. coin. ,uunic:diotu node:. 11.1'. all lands.	to O0 mbtre:. Solo'
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