Radio Broadcast (May 1929-Apr 1930)

"Z. RADIO BROADCAST service shop is a list of apparatus to be used. As there are still a great many batteryoperated sets in use as well as the various types of electric sets, adequate apparatus must be available for testing and repairing both types. All instruments should be purchased for their accuracy, convenience, and ruggedness. They will be subjected to hard wear. An ample outfit, containing meters and tools which will enable any qualified radio serviceman to make any test required in locating set troubles, and for making all repairs, is suggested as follows: The work bench: The design of this piec > of equipment is most important. It should be 2 feet deep, 36 inches high, and made of heavy pine boards 2 inches thick. (Two 12" x 2" planks 12' long recommended.) The legs should be made of 4" x 4" lumber, so that it will be perfectly steady. The bench should be located in such a way that daylight comes in from the back, with each serviceman facing a window. There should be from 4 to 5 feet of bench room allowed for each man, and each man should have a drop light hung directly over his work. A stool of comfortable height should be provided each man for long jobs. Shop servicing equipment: Electric soldering irons, capable of giving sufficient heat for extended work without burning out (One large electric shop in Washington uses the old-time plain irons, keeping several of them hot around a small gas ring.); wide assortment of well-constructed steel screw drivers; set of small open-end hexagonal wrenches; assortment of pliers and wire cutters of a good grade; set of hexagonal socket wrenches; assortment of fuses used in sets to be serviced ; assortment of spring clips for making quick connections; several pairs of test prongs with wires; a small jaw vice; hydrometer; package of 00 sandpaper, and an electrician's steel knife. Instruments needed: High-frequency oscillator; a.c. and d.c. tube tester; d.c. voltmeter with double-reading scale, 0-15 and 0-150; high-resistance voltmeter, 0-10 and 0-200; d.c. ammeter, 0-5; a.c. voltmeter, 0-3 and 0-5; and d.c. milliammeter, 0-100. Power: All A, B, and C voltages for testing battery-operated sets should be wired to binding posts or clips on the work bench, as indicated in Fig. 4. There must also be a double outlet from the a.c. power fine wired to the bench for use in testing a.c.-operated receivers. Where the shop is in the d.c. district of a city the most convenient method of handling the a.c. set problem is to install a motor-generator, running on d.c. and giving 110 to 115 volts a.c. output. The power rating of this generator depends on the load to be placed on it. A one-fourth-kilowatt generator is about sufficient for operating one a.c. set at a time. Two popular motor-generators, designed for this purpose and including filter, Fig. 2 -In this carefully planned showroom antennaground outlets have been installed in several convenient positions. are the 250watt, 11 5volt, type be-24, made by the Bodine Electric Co., Chicago, and the 500-watt, 115-volt, type lf-85, made by the Electric Specialty Co., Stamford, Conn. Antenna and ground: Erect separate antenna for shop, and wire to bench. Also wire good ground to bench. Loud speaker: Place good loud speaker on a wall shelf, or other elevated position above bench for convenient plugging in. It is generally necessary to use an extension cord for this purpose. Outside serviceman's equipment: One oscillator voltmeter test combination; one test set, or assortment of meters with prongs or wires ; such hand tools as are required for making minor repairs — screw driver, knife, hydrometer, pliers, soldering iron, phones, and a number of spare tubes of different types. The equipment listed above should rep Fig. 3— Diagram showing the floor plan of the Capitol Radio Service Shop, Washington, D. C. resent the initial outlay for a small radio service shop. Special tools may of course be added. Among these would be special wrenches, neutralizing tools which some sets require, etc. Layout of Equipment THE service shop should be located, when possible, in the rear of the salesroom, so that customers can be referred readily to the service department, using a minimum of the sales force time. The outside serviceman should have access to the serviceroom through the rear of the building. The shop should be well lighted, if possible by daylight. The lighting shown in Fig. 1 is ideal. Glass jars, seen in the photograph on the wide window sill, are used for holding spare parts for repairs. Adequate shelf room must be provided for holding incoming and outgoing sets, and a carefully handled system of tagging and filing is necessary in order to avoid confusion concerning ownership of the sets, their history, etc. Stout paper shipping 1 ^<<ma>^ | Radio Parts Counter Show Case " Counter Elec. Shelves Dressing Room Jt/ > / y /V , SHOW ROOM Shelves OFFICE SHOP Sink • may, 1929 page 11 •