Radio Broadcast (May 1929-Apr 1930)

RADIO BROADCAST motor, $25.00; type 301 Electrovox consisting of a type 140 motor installed in a cabinet, $75.00. Motors for Phonographs General Industries Company: A complete line of spring and Electric motors for phonograph and phonograph-radio combinations are 3— ' manufactured by this company. The standard electric motor types are designed for 110-volt 50-60 cycle a. c. operation. The large spring motors have a capacity of about five standard 10" records from one winding. New Dynamic Chassis Trimm Radio Manufacturing Company: A dynamic loud speaker chassis has been developed by this company. The Model d100 is designed to be supplied with field power from the power unit. The Model dv102 is supplied with an output transformer to match conventional types of power tubes. Phonograph Apparatus Ultraphonic Products Corporation: This company is manufacturing the Upco electric phonograph pick-up unit which is sold complete with tone arm and volume control. The impedance is 600 ohms at 1000 cycles and the output is 1.2 volts at 200 cycles. Lists complete at $20.00. Radio Service Material Louis P. Horning, Jr. Laboratories: This company supplies radio service material such as record cards, service call cards, letter heads, etc. A test bench has been designed with the requirements of radio service work in mind. It is made of heavy material with ample space for handling complete sets, and space for a large test panel. Net price: $29.00. New Lightning Arrestor L. S. Brach Manufacturing Corporation: The Arres-Tenna is a new protective device designed to protect radio receivers against lightning which may reach the set either through the antenna or through the lighting system. The device lists at $2.50 and carries a $100 insurance guarantee. Belden Antenna Kit Belden Manufacturing Company: A new complete antenna kit containing every item of material needed to install a complete antenna and ground system has been placed on the market by this company. New Eveready Series 30 National Carbon Company : The Eveready Series 30 (Models Nos. 30 to 40) receivers employ a seven-tube single-dial antennaoperated all-electric a.c. chassis, having three stages of r.f. amplification, detector, and two stages of a.f. amplification. The power stage consists of two 171a tubes in push pull. The rectifier is a type 280. The receiver employs a variometer in the first tuned circuit, thus making the sensitivity of the set more uniform throughout the entire broadcast baud. Elect rad Resistors Electrad, Incorporated: Several new lines of fixed and variable resistors are being manufactured as follows : Super Tonatrols, a group of heavy-duty volume-control resistors, in values from 10,000 to 50,000 ohms; Truvolt sliding contact resistors, in values up to 5000 ohms; Truvolt air cooled resistance banks, in values up to 21,000 ohms; Wire-wound grid leaks, in values from 5,000 to 50,000 ohms. Amperite Line Control Badiall Company: The Amperite selfadjusting line voltage controls for a.c. receivers are designed to handle a line fluctuation of about 30 volts maintaining the output constant within about 10 per cent. The voltage drop across the control varies from about 20 to 40 volts, so that the transformer primary must be wound for about 80 volts. The manufacturers guarantee a life of about 2000 hours. Automatic Tuning Control Carter Badio Company: An automatic control tuning device was recently announced by this company. It cannot be attached to an existing receiver but is designed to be incorporated into the set during its manufacture. The device is operate:! by pressing push buttons each of which functions to tune the receiver to the station whose call letters are indicated on the button which was pressed. When a button is pressed an arm makes contact with a drum. This closes the motor circuit which immediately begins to revolve and continues to do so until the variable condensers have been brought to the correct point to receive the desired station. The device is also adaptable to remote-control operation. Any number of remote-control devices may be employed to control the receiver from various locations. The device was designed by A. W. Plenser, engineer of the Carter Badio Company. New Diaphragm Material Stevens Manufacturing Company: This company makes a special diaphragm material which is used in a number of dynamic loud speakers being made by various set manufacturers. The diaphragm material is known as Burtex and consists of a special fabric which can be pressed into any desired shape and impregnated with a water-proofing compound to make it impervious to moisture. Burton-Rogers Tube Checker Burton-Bogers Company: The new Model B tube checker is equipped to test both a.c. and d.c. screen-grid tubes as well as all other standard types of tubes. It is completely supplied with power from the a.c. lines and a tube is checked by simply putting it into the ap propriate socket and noting the reading of the single meter The net price to dealers is $22.75. New Phonograph Pick-up E. Toman and Company: The Toman Super Pick-up is designed for use in electrically reproducing phonograph records. List price is $17.50. Phonograph Pick-Up Units Buckingham Badio Corporation: This company makes several types of electric pick-up units as follows: Model A — Pick-up only. Manufacturer's type $10.00 Model A-l — Pick-up only with bracket 10 . 45 Model b-201 — Pick-up with bracket, volume control unit, and adapter for d c. sets 15 . 45 Model B-227 — Pick-up with bracket, volume control unit, and adapter for a.c. sets 15 . 55 Model c — Pick-up only with tone arm, Manufacturers' type . . . . 14.00 Model c-201 — Pick-up with tone arm, volume control unit, and adapter for d.c. sets 19 .00 Model c-227 — Pick-up with tone arm, volume control, and adapter for a.c. sets 19 . 00 201 — Adapter model for d.c. sets. . 1.25 227 — Adapter model for a.c. sets . . 1.35 "X-Core" Dynamic Speakers The Magnavox Company: The "X-Core" dynamic loud speakers made by this company are available in a number of different models. Either the unit alone or the unit mounted in a cabinet may be purchased. The units are priced as follows: No. 106—71" cone, 110-190 v. d.c. $21.00 No. 107— 102l" cone, 110-190 v. d.c. . 23 .00 No. 108— 7 \" cone. 180-300 v. d.c. . 2100 No. 109—101" cone. 180-300 v. d.c. . 23 00 No. 200— 7 \" cone, 6-12 v. d.c. . . 22 .00 No. 201 — 10^" cone, 6-12 v. d.c. . . 24 00 No. 400— 7-J-" cone, 105-120 v. a.c. 60 cycles 31.00 No. 401— 10 j" cone, 105-120 v. a.c. 60 cycles . .... 33 00 No. 402— 7 f"' cone, 105-120 v. a.c. 25 cycles 32 . 00 No. 403— 10J" cone, 105-120 v. a.c. 25 cycles ........ 34 . 00 Jewell Set Analyzer Jewell Electrical Instrument Company : A new four-instrument set analyzer designed to meet all the requirements of modern set testing has been designed by this company. Space is provided for carrying tools and replacement tubes. Automobile Receiver Automobile Badio Corporation: This company makes the Transitone radio receiver designed for installation on the dash board of automobiles. The antenna is concealed in the top of the car and the loud speaker is attached above the windshield or hidden under the dash board. • OCTOBER 1 92 9 • • 343