Radio Broadcast (Nov 1926-Apr 1927)

322 RADIO BROADCAST ADVERTISER FROST-RADIO Parts and Accessories As important as the tubes, batteries or loud speaker used in your set, are the parts and accessories you select for building your receiver. There will be no doubt about the quality of these parts or their dependability if you go to your dealer and ask for f HOST' RADIO parts and accessories. FROST RADIO Super Variable Resistances For controlling volume, tone and regeneration. Non-inductive, smooth and noiseless in operation. Provide stepless variation from zero to maximum. Type 880, two terminals, and Type 890, three terminals, either type, $1.25, in all resistList Price, $1.25 ances. FROST-RADIO Metal Frame Rheostats A simple, sturdy rheostat for little money, that has all of the electrical qualities of our Hakelite type. Metal frame cannot bend or warp, and shaft alignment is permanent. Single hole mounting. Supplied in resistances from 2% to 75 ohms — 50c. Frost-radio Bakelite Rheostats Their cast frames of genuine Bakelite permit free circulation of air around windings. Oversize current carrying capacity prevents overheating. Operation is smooth and noiseless. The finest rheostats money can buy, yet is not high priced. Any resistance, 2y2 to 75 List Price, 75c ohms, 75c. FROST RADIO No. 141 Automatic 2-Fone Plug List Price, 75c HERBERT H. FROST, Inc. 160 North La Salle Street CHICAGO New York Los Angeles List Price, 50c |Biai^^AmjJifier5 ■» Resistance Coupled V ^PERFECT AUDIO AMPLIFIER": v^e j illLfirils ^ *■ Provides audio amDltflrBtlon with minimum ditttoitWi. Hrndlevunit ■_ molded irHiLtom uned In tho Br adley Amplifier Hi do not vnry with ago and are not affected by ntmoBnhe rlc ■U conditions. <'«n be, Died •<> renlnm trannformer amplifiers in stundard radio uetuwith decided Id crease intone quality. > £gfin-Biar%r Co. ■s Electric Controlling Apparatus J» 278 Greenfield Avenue Milwaukee, Wis. Manufacturers' Booklets Available A Varied List of Books Pertaining to Radio Free by Using the Accompanying Coupon AS AN additional service to Radio Broadcast readers, we print below a list of booklets on radio subjects issued by various manufacturers. Already, a regular feature of this magazine is an analysis of the best material in current radio publications, and a series of Laboratory Data Sheets, both of which present concise and accurate information in such a form as to be readily used. The publications listed below cover a wide range of subjects, and offer interesting reading to the radio enthusiast. The manufacturers issuing these publications have made great effort to collect interesting and accurate information. Radio Broadcast hopes, by listing these publications regularly, to keep its readers in touch with what the manufacturers are doing. Every publication listed below is supplied free. In ordering, the coupon printed on page 324 may be used. Order by number only. — The Editor. Parts 1. Hook-Ups — Problems of filament supply, voltage, regulation, and effect on various circuits. Radiall Company. 2. Hard Rubber Panels — Characteristics and properties of hard rubber as used in radio, with suggestions on how to " work" it. B. F. Goodrich Rubber Company. 3. Audio Transformers — A booklet giving data on input and output tran sformers. Pacent Electric Company. 4. Resistance Coupled Amplifiers — A general discussion of resistance coupling with curves and circuit diagrams. Cole Radio Manufacturing Company. 5. Carborundum in Radio — A book giving pertinent data on the crystal as used for detection, with hook-ups, and a section giving information on the use of resistors. The Carborundum Company. 6. B-Eliminator Construction — Complete constructional data on how to build. American Electric Company. 7. Transformer and Choke-Coupled Amplification — Circuit diagrams and discussion. All-American Radio Corporation. 8. Resistance Units — A data sheet of resistance units and their application. WardLeonard Electric Company. 9. Volume Control — A leaflet showing circuits for distortionless control of volume. Central Radio Laboratories. 10. Variable Resistances — As used in various circuits. Central Radio Laboratories. 11. Resistance Coupling — Resistors and their application to audio amplification with circuit diagrams. DeJur Products Company. 12. Distortion and What Causes It — Hook-ups of resistance-coupled amplifiers with standard circuits. Allen-Bradley Company. 13. Materials for Screw Machine Products— Comparative costs of steel and brass with data and actual examples of how to specify. Bridgeport Brass Company. 14. Ordering the Right Kind of Sheet Brass — How to specify the proper grades for various purposes. Bridgeport Brass Company. is M-Ei.iminator and Power Amplifer — Instructions for assembly and operation using Raytheon tube. General Radio Company 15a. B-Eliminator and Power Amplifier — Instructions for assembly and operation using an I R. C. A. rectifier. General Radio Company. -J( Examined and approved by Radio Broadcast -jf 16. Variable Condensers — An ambitious description of the functions and characteristics of variable condensers with curves and specifications for their application to complete receivers. Allen D. Cardwell Manufacturing Company. 17. Bakelite — A description of various uses of bakelite in radio, its manufacture, and its properties. Bakelite Corporation. 18. Brass Rods — Details of manufacture together with tests and specifications. Bridgeport Brass Company. 19. Power Supply — A discussion on power supply with particular reference to lampsocket operation. Theory and constructional data for building power supply devices. Acme Apparatus Company. 20. Audio Amplification — A booklet containing data on audio amplification together with hints to the constructor; also some general radio information. All-American Radio Corporation. 21. High-Frequency Driver and ShortWave Wavemeter — Costructional data and application. Burgess Battery Company. Accessories 22. A Primer of Electricity — Fundamentals of electricity with special reference to the application of dry cells to radio and other uses. Constructional data on buzzers, automatic switches, alarms, etc. National Carbon Company. 23. Automatic Relay Connections — A data sheet showing how a relay may be used to control A and B circuits. Yaxley Manufacturing Company. 24. Detector Tubes — A brief outline of tube operation. C. E. Manufacturing Company. 25. Electrolytic Rectifier — Technical data on a new type of rectifier with operating curves. Kodel Radio Corporation. 26. Dry Cells for Transmitters — Actual tests given, well illustrated with curves showing exactly what may be expected of this type of B power. Burgess Battery Company. 27. Dry-Cell Battery Capacities for Radio Transmitters — Characteristic curves and data on discharge tests. Burgess Battery Company. 28. B Battery Life — Battery life curves with general curves on tube characteristics. Burgess Battery Company. 29. How to Make Your Set Work Better — A non-technical discussion of general radio subjects with hints on how reception may be bettered. United Radio and Electric Corporation. 30. Tube Characteristics — A data sheet giving constants of tubes. C. E. Manufacturing Company. 31. Functions of the Loud Speaker — A short, non-technical general article on loud speakers. Amplion Corporation of America. 32. Meters for Radio — A catalogue of meters used in radio with connecting diagrams. Burton-Rogers Company. 33. Switchboard and Portable Meters — A booklet giving dimensions, specifications, and shunts used with various meters. BurtonRogers Company. 34. Cost of B Batteries — An interesting discussion of the relative merits of various sources of B supply. Hartford Battery Manufacturing Company. 35. Storage Battery Operation — An illustrated booklet on the care and operation of