The radio dealer (Apr-Sept 1922)

July, 1922 THE RADIO DEALER 57 Piloting Cable. Describing the test of this method of steering a ship through a fog, Motor Boating said in a recent issue : " One of Uncle Sam's big new destroyers was piloted from Ambrose Channel Lightship to the Narrows without the use of vision on the part of the pilot and helmsman. A canvas screen had been stretched completely across the pilot-house windows and the pilot stood facing aft. As far as visibility was concerned the conditions were equal to what would be encountered in the thickest fog in the middle of the very blackest night. The simple little apparatus that made this marvelous feat possible consisted of a pair of coils, one on either bow of the vessel and connected with a vacuum-tube amplifier which picked up the magnetic field created around a submarine cable energized by a lowfrequency alternating current." The United States Navy used the device during the war, and recently signed a contract for its use during the stirring times of peace, when the thrills of inventive genius supplant the excitement of slaughter. NEW STYLOLECTRIC PEN The Post Styloletric Pen is an electrically operated writing stylus of good design and construction. It can be used on the ordinary D. C. or A. C. lighting circuits, and a lamp attachment permits the regulation of current flow, and controls the heating of the element. It can be used to mark wood, leather, paper, fiber or any kind of material by means of colored sheets of transfer paper. The holder is made of an insulating composition, which precludes the possibility of the current coming in contact with the body. A heating element provides the heat for the penpoint. Good ventilation is provided for at the base of the holder, so that the heating unit will not get over-heated, and burn out. This pen will work on about a quarter of an ampere according to an expert who recently tested it. This current can be varied, for various purposes, such as for cauterizing, soldering, etc., up to one-half an ampere. An extra attachment, in the shape of soldering copper makes this pen very convenient for delicate soldering jobs in the laboratory. It is furnished with instructions, transfer paper, six feet of cord and several attachments. The device is guaranteed for one year by the manufacturers. It is made by the Post Electric Co., 30 East Forty-second street, N. Y. Parts — THE uniform quality and attractive prices of ABC Radio products bring profitable business to dealers who want advertised lines of quick turnover. ABC Variable Condensers TV/f ANUFACTURED in our own factory and containing many special features. No. Plates Price 650-43 43 $5.00 650-21 21 3.75 650-11 11 3.00 650 3 3 2.25 Send us your stock order on this big seller today. ABC Transformer T? VERY part securely "^-/ fitted under pressure and the whole held together in one solid unit. Magnetic leakage is impossible in the A B C. Price $7.00 ABC Headsets npWO standard Murdock head phones with improved Signal Corps type headband. No. 770— L2 — 2000 ohms 5.50 No. 770— L3 — 3000 ohms 10.50 No. 770— ABC headband alone. 1.50 Send today for full information about ABC Parts and how we help you sell them. JEWETT MANUFACTURING CORPORATION 342 Madison Ave. Dept. F7 NEW YORK