History of wireless telegraphy and broadcasting in Australia/Topical/Publications/Australasian Radio World/Issues/1948 03

P.01 - Front Cover

The Australasian Radio World

Registered at the G.P.O., Sydney, for transmission by post as a periodical.

1/-

Vol. 12 - No. 10; MARCH 15, 1948

P.03 - Contents Banner

THE AUSTRALASIAN RADIO WORLD

Devoted entirely to Technical Radio

and incorporating

ALL-WAVE ALL-WORLD DX NEWS

VOL. 12 - MARCH, 1948. - No. 10

P.03 - Publication Notes

Editor, Publisher, Proprietor — A. G. HULL, Balcombe St., Mornington, Vic.

Short-wave Editor — L. J. KEAST, 6 Fitzgerald Road, Ermington, N.S.W. 'Phone: WL1101

Ham Notes By — D. B. KNOCK (VK2NO), 43 Yanko Av., Waverley, N.S.W.

Advertising Representative for N.S.W. - Amalgamated Publications Pty. Ltd., 83 Pitt St., Sydney, Phone: B1077

Representative in Queensland - John Bristoe, Box 82, Maryborough, Q.

Representative in England - Anglo Overseas Press Ltd., 168 Regent St., London, W1.

Subscription Rates: 12 issues - 10/6; 24 issues - £1; Post free; To N.Z. and Overseas - 12 issues, 12/-

Address for all correspondence - Australasian Radio World, Balcombe St., Mornington, Victoria

Printed by Bridge Printery Pty. Ltd., 117 Reservoir Street, Sydney, N.S.W., for the proprietor of the "Australasian Radio World," Balcombe St., Mornington, Vic. (Footnote P.44)

P.03 - Contents

CONTENTS

TECHNICAL —

In Search of Fidelity . . . . 5

A Modern Battery Receiver . . . . 9

Radio World Review . . . . 11

Among Our Readers . . . . 15

A Personal Portable . . . . 19

3-Valve Triple-Wave Receiver . . . . 27

Calling CQ . . . . 34

SHORTWAVE REVIEW —

Notes From My Diary . . . . 38

THE SERVICE PAGES —

Speedy Query Service . . . . 42

P.03 - Editorial

EDITORIAL

Ever since the earliest days of radio, most of us have been battling to get a wider and flatter frequency response from our amplifiers. Now things have advanced to such a stage that it is fairly easy to get a set-up of the flattest and widest response, such as a Lexington pick-up, Williamson amplifier circuit, and Goodmans speaker. I have such an outfit in operation and I can tell you that it is useless with the ordinary records as sold in the shops to-day. Using the amplifier and speaker with, a wide-band tuner it is possible to get some brilliant results on radio from certain "live" broadcasts, but to enjoy the reproduction of gramophone recordings it is essential to lop off the highs. Lest you imagine that all is lost, I hasten to say that the latest wide-range pick-ups have more than mere wide range, their wave form on the normal frequencies is better than that of the old magnetic pick-ups; the amplifiers with triodes and inverse feedback have low distortion as well as wide range; the high-fidelity speakers can handle the middle register well. It seems strange that we should have to strive so hard for wide-range reproduction and then turn around and lop off the highs, but that is the position at the moment with ordinary records. Later when full frequency range records become available things may be different. In the meantime I can only recommend true wide-range equipment for radio work, and it has its draw backs there, too. Static and noise are both reproduced with added brilliance in a manner which you won’t appreciate. — A. G. Hull.