RADIO AND ITS RECEIVERS

Sun (Auckland), Volume II, Issue 593, 20 February 1929, Page 14

RADIO AND ITS RECEIVERS

R. F. HAYCOCK.

Conducted for THE SUN by

Umbrella Radio LATEST IN FREAK SETS Music While Yoli Walk

A RADIO receiving set simulating an umbrella has been invented and patented. This odd receiver takes the exact form of an umbrella, including the cloth canopy, ribs and handle. It opens and closes, and when in either position it is so cleverly disguised that the head phones connected near the handle are the only visible evidence to betray its real identity.

rpHE inventors admit that this strange contrivance is the result of that axiom of necessity being the mother of invention. The indoor coil and loop antenna manifestly are not so readily adapted to outdoor conditions, with the attendant adverse weather of Tain or snow, and yet the compact coil or loop of wire is otherwise to be desired for service afield. The inventors modify this timehonoured shelter so as to incorporate a complete radio receiver, including antenna and head telephones—using a crystal detector as an expediency in avoiding the necessity for batteries. Directional Properties The combination of these elements on a collapsible frame, with handle, similar to the frame of an umbrella, furnishes a complete radiation-receiy-ing apparatus without any supplementary connection. Such a portable receiver permits the operator to receive communication without interruption while moving from one place to another and, by virtue of its directional properties, affords a convenient and inconspicuous means of locating a radiation source by a process of triangulation from two or more observing points. The flexible conductors, or multiturn conductors, comprising this novel radio-receiver, are sewed to the edge of an umbrella cover, or otherwise incorporated in the insulative cover fabric. That is to say, the umbrella frame may consist of any kind of material. A common form of frame, however, has flexible metal ribs and stretchers assembled on a hollow steel rod. This rod serves to disguise and protect the insulated lead, while the rod itself acts as the other part of the circuit. The side of the circuit in electrical contact with the rod and ribs lead directly to the head telephones, while the crystal-contact detector connects to the protected side of the circuit. This arrangement permits of the grasping of the umbrella handle with the hand without appreciably changing the electrostatic capacity of the circuits on which tuning and strength of incoming signals depend. When this umbrella-radio receiver is closed, the flexible conductor occupies very little space, and yet when the umbrella is spread out it has sufficient surface area to intercept signals from near-by broadcasting stations and to actuate the instruments which render these signals audible. An additional advantage of the

umbrella-radio receiver, is that the inductance of the coil may he adjusted by partly opening or closing this disguised umbrella. The central rod of the frame-work may be equipped with a scale or calibration for indicating the frequency or wave-length for which the outfit is tuned. By its very spectacular nature and odd formation, this umbrella-radio receiving set falls into the category of freaks. This is true whether it is

employed as proof against a rainy day, while at the same time picking up programmes from a local broadcasting station or as a novel advertising stunt. There are other freak receiving sets —the coconut, on which is mounted a crystal and tuning device, a finger-ring, built up into a tiny receiver, and a walking-stick converted into a miniature radio reproducer—ail falling into the category of novel, interesting and occasionally entertaining, but withal freakish devices.