A Remarkable midget radio receiver-transmitter developed for the Australian Army is so small and light that it is carried in two ammunition pouches on a signaller's belt.

Not only is it half the weight of sets now in use, but it is also superior in performance in all respects, according to the radio engineers who worked on its development.

Mr. Howard Beale, Australia's Federal Minister for Supply, announced in January that the first order for 1,400 sets at a cost of Rs. 36,26,600 had been placed for the Army with Amalgamated Wireless (Australasia) Ltd. The technical service establishment in the Army branch of the Department of Supply designed and built the radio with the help of Amalgamated Wireless.

Mr Beale said that the set would revolutionise field communications in actual warfare. "No set so light, compact and powerful has been developed anywhere else in the free world", added the Minister.

Prototype sets weight 17 lbs. -half the weight of existing sets- but newer models have been reduced to 15 Ibs. Batteries are half the weight of those used in present sets and have twice their life.

Contact can be established with the base station with the new set in 50 seconds compared with 10 minutes with present sets. It operates on a broader frequency band which enables signallers to establish communications quickly and clearly in any weather conditions.

Lightness, reliability and simplicity of operation and maintenance are the main attributes of the set.

Some aspects of it are secret, but Army branch designers say that it involves no new principles. Its radical reduction in size and weight is the result of all-round reduction of component parts to the smallest possible size and ingenious packing size and ingenious packing into the smallest possible space. Everything is in miniature, even the handset for listening and speaking, and the key for morse transmission.

Marked development in the radio industry in the last three years, say the radio engineers working on the project, has produced more reliable and smaller radio components and has been an important factor that helped to make the baby set possible. It was designed for quantity production using entirely indigenous parts- a safeguard against interruptions in supply of parts.

The radio can be used as a "man-pack station’, or as a ground station. When it is being used "on the march" as a portable set, it is carried in two pouches attached to the signaller's belt and fitted with a light whip aerial. In this role it has a range of three to five miles.

But set up as a ground station with a slightly more elaborate aerial, it has a range of 50 to 100 miles, according to the nature of the surrounding country. As a ground station, too, it enables contact to be established in two minutes instead of 40.

The small batteries fitted into the self-contained set are the bulkiest item. They have an operating life of about 15 hours. If the batteries run out, the radio can be operated by a pedal generator.

Work started on the set over two years ago to meet the Army's need for a lighter set that could be carried more easily by fighting patrols. Much of the credit for its development goes to a 33-year-old English radio engineer working in the technical services establishment of the Army branch.