Aid For Radio Owners

AN apparatus which has been approved by wire less set owners in Australia and Great Britain is now being introduced to the Pacific Islands.

It is called the Milnes H.T. Supply Unit, and its purpose is to eliminate the cumbersome and expen sive “B” dry batteries that are the bugbear of every radio owner in the South Seas.

Radio receivers require three distinct forms of current supply: Low tension, grid bias, and high tension. Low tension accumulators are inexpensive and last a long time. They can be recharged periodically at the cost of a few pence. Grid bias batteries cost even less, and are good for a year or so. The supply of high tension (anode) current, however, presents a more difficult problem.

The most widely used source of H.T. supply is the “B” dry batterv. For a month or so the battery functions perfectly; then gradually the volume weakens. Increasing the reaction to restore the lost volume, the set-owner only imposes a still heavier drain upon the battery. Suddenly an ominous crackling from the loud speaker mdi cates that the battery is nearing exhaustion and, finally, as it cannot be recharged, it is heaved out.

This new apparatus takes the place of dry bat teries, and maintains an even, full-strength cur rent. It is recharged automatically from a low tension source of supply—usually from a 6 volt wet battery already in use in the set or from a car battery. The Milnes unit has a potential of 5 volts, and when connected with a 6 volt battery, by means of the charging terminals, a flow of cur rent caused by the 1-volt difference goes into the lower powered unit. This current gradually diminishes as the volume of the Milnes apparatus rises and becomes fully charged.

With normal care and treatment the unit is practically indestructible. The plates and connec tions are nickel and silver arid a special compound used prevents their corrosion. The life of a Milnes unit is claimed to be at least 20 years.

Readers who are interested in this handy appara tus may obtain pamphlets, explaining technically the system under which it operates, and informa tion from Messrs. Kriesler Australasia Limited, the well-known Australian radio firm, which is the Pacific Islands distributor for the Milnes High Tension Holden’s Air Transport Services Ltd. has declared an interim dividend of fid. a share (equal to 10 per cent, yearly) for the quarter ended September 30.