Radio mirror (Jan-Oct 1923)

RADIO DIGEST — Illustrated August 4, 1923 SURVEYS INDUSTRY'S TANGLE OF PATENTS ^'Cooperative Competition" Leaves Maze of Stumbling Blocks for Independent Manufacturer By John B. Brady (Editor's Note,— Mr. Brady, a patent attorney of Radio repute, has achieved a remarkable survey of the nettoork of patents, locking and interlocking the Radio industry in a veritable Gordian knot. Sis serial treatise on the patent situation started July li issue.) PART XV MANY claims for patent infringement were filed against the government for the manufacture and purchase of Radio apparatus from others than patent holders under the "save harmless" contracts, and many of these claims, although severely contested over a period of years, are still pending. The government in operating its chain of high power Navy Radio stations and Signal Corps net, appreciated the value of a patent situation and acquired where possible licenses in the several inventions indicated by the chart. The Federal Telegraph Company by further negotiation with the government secured a retransfer of the title to its patents covering the arc transmission system and extended certain licenses thereunder for the broader commercializa Westinghouse Electric and Manufacturing Company. Independent Organizations Among the independent organizations represented on the chart herewith there is the Independent "Wireless Telegraph Co., including the Cutting and Washington Co., who have recently been sued by the "Wireless Specialty Apparatus Co., under the Pickard loop patent 876,996. The Liberty Electric Corporation is licensed under the Federal arc patents by an agreement with the government whereby the government obtained licenses under certain inventions on the arc by engineers of the Liberty Electric Corporation. The license is restricted to arcs up to ten kilowatts. The Inter-City "Wireless Telegraph Co., has recently been successful in a mandamus suit against the Secretary of Commerce, compelling the Secretary to renew an operating license to the company. The suit was favorably decided for the InterCity Co., by the supreme court of the District of Columbia and has now been appealed by the Secretary of Commerce to niLLER. fcEESE HUTCHISON HALL RESEARCH COKP. MALLORV STEAt^SHIP CO. FEOERALTELEPHOKE <ST£LKRAPH CO BUFFALO N.V INDEPENDENT WIRELESS TELEGEftPH CO NEW YORK CITY. CUTTING £WASH CO. LIBERTY ELECTRIC COMPANY LICEN5E FEDERAL TELEGRAPH CO. PATENTS ARCS UPTOIOKW SHIP OWNERS RADIO SERVICE INC. C.B. COOPER, KILBOURNE<£ CLARKE MFG. CO. \NOEPENDENT AM6TEQR, MANUFACTURES JEWETT PHONOGRAPH CO. OWNER.* OF OE FOR.EST RADIO TELEPHONE «TE1E6RAPH CO. INTERCITY WIRELESS TELEGRAPH CO. CMIL O.SIMON INC. STATIONS • AT NEVJYOfcK DETROIT CLEVELAND BUFFALO Radio Patent Organization Chart tion of the arc system. Having secured a return of its patents the Federal Telegraph Company were again potentially strong and, in working out the Chinese high power Radio station contracts entered into a license agreement with the Radio Corporation forming a Federal Telegraph Company of Delaware and of California. Government Strengthens Situation The government since the close of the war had also been perfecting its patent situation to a point where rights existed under the multiplex telephony patents of General Squier, the arc patents, alien owned Radio patents seized by the alien property custodian and purchased by the Navy, the Rogers and Lyon underground antenna patents, the Kolster direction finder patents, the Cohen statically coupled receiver patents, the Dubilier condenser patents, the Sperry airfan generator patents for aircraft Radio, the "Vreeland beats and oscillators patents, the patents controlling the Hanson audio frequency system and piloting cable, and numerous inventions by employees of War, Navy, Commerce and Post Office Departments, including a license under the heterodyne, and patents of the International Radio Telegraph Company and the United States Supreme Court to determine whether or not the Department of Commerce has authority to decline to reissue, a license to any station previously found interfering with other traffic. The DeForest Radio Telephone and Telegraph Co. has certain rights under the many Stone and DeForest patents. It was under the DeForest tube patents that the agreement was made with the Radio Audion Co., manufacurers of Myer tubes. Course Open to Independents The independent amateur manufacturers have been represented on the chart with these independent organizations. The striking analysis brought out by the chart is that if the independents are to share in the monopoly exercised by the Radio Corporation they must enter by way of a patent situation which the corporation 5 GOOD REASONS WHY you should own a RITTER PORTABLE LOOP Lightning — Cranky landlords — Ugly antennas — Static — Interference. Bitter loops can be assembled in 5 minutes. Instructions with every loop. Price $1.00. By mail, 10c extra. RITTER RADIO CO, 230 Canal Street New York FLEWELLING ANSWERS TO QUERIES -By E. T. Flewelling (Editor's Note. — This department is written by Mr. Fie welling, the inventor of the famous super circuit. From the questions sent him each week care of Radio Digest, he picks the one considered most informative for all and answers it in this column.) Types of Plewelling1 Supers (Submitted by E. H. T., Seattle, Wash.) Question. I have been using the Flewelling circuit for some time with honeycomb coils and the bank of three condensers but I would like to reconstruct the set to improve its looks and in doing so would like to take advantage of the simplified form of circuit which uses but one condenser. Would it be possible for me to use a variometer instead of the usual tickler coil, as I understand that the use of a tuned plate circuit is of more advantage on the short wave lengths? Answer. When the first experiments were carried on with the Flewelling circuit we were unable, seemingly, to use a variometer in the circuit. In one of the earlier articles this was discussed. Mention was made that there was no reason why a variometer could not be used, but at the time we were unable to find one that was suitable. The answer to your question is that a variometer certainly can be used and does offer slight advantage, due to enabling the tuning of the plate circuit. In the first place any standard variometer will operate. We have found that a certain amount of advantage seems to result from the use of a bank wound variometer. This is a little touch of refinement; I would not recommend its use if you have one of the standard types on hand. Note also that you must give the circuit a small fraction of a second in which to go into must recognize. This is true of all of the patents gathered together under the cross license agreement in the Radio Corporation. A well-known author once said, if a man writes a better book or preaches a better sermon or builds a better rat trap, even though he lives in the woods, the world will beat a path to his door. This is a policy which the small manufacturer should adopt by building such a patent situation that instead of the Radio Corporation forcing him out of the industry it will be compelled to welcome him into the industry and extend license privileges under its patents in reciprocation of license privileges under patents owned by the small manufacturer. The situation is one which compels concentrated effort in patents on the part of every manufacturer who wishes to grow in this remarkable industry. (THE END) operation when first starting. I speak of this because one is very likely to turn the variometer control so fast that they go past the point at which it works properly. Of course if you use a variometer you are always sure that your circuit will work upon finishing the set provided the wiring and the like are right, meaning by this that you will not have to worry about the proper polarity of the tickler coil as you would when using that type of circuit, w Figure 1 There have been so many inquiries cov ering the various types of Flewelling super circuit that I believe it would be a good idea to show a few variations of the circuit. Take, for instance, Figure 1. This diagram shows the type of circuit that you speak of with a variometer tuned plate circuit and an inductance coil for tuning. This type of circuit may also be used (Continued on page 8) BOOK OF 100 RADIO HOOK-UPS by Expert Radio Engineers Every one of these hook-ups will give you OKr excellent results. 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THE POST SOLDERING IRON Platinum Heating Unit — Interchangeable Tips — Universal Current {Large and Small) % 6\y ONE-HALF ACTUAL SIZE Awarded Certificate of Excellency, N. Y. Evening Mail Radio Institute From your Dealer, or write POST ELECTRIC COMPANY (Dept. 509), 30 E. 42nd St, New York WILLARD RADIO COMPANY 291 BROADWAY NEW YORK CITY FLEWELLING CIRCUIT Co£&?' Baseboard, two honeycomb coils, mountings and coil plugs, 3 .006 condensers, .002 phone condenser, variable grid leak and condenser, grid leak ','2 meg, 23 plate variable condenser, vernier rheostat, tube socket 3" dial, ft binding posts, 16 ft. bus bar, PANEL ALREADY DRILLED, TOGETHER WITH DIAGRAM AND (11 Qp INSTRUCTIONS «p 1 1.170 Parts for TWO-STAGE AUDIO FREQUENCY AMPLI with drilled panel and book of instructions REINARTZ CIRCUIT °<%&?e Baseboard, Reinartz coil increased wave length, tube socket, vernier rheostat, 23 plate and 13 plate variable condensers, 3 inductance switches, 2 3 dials, variable grid leak and condenser, .002 phone condenser. 16 ft. bus bar, 23 switch points, 29 nuts 6 stops, 8 binding posts, PANEL ALREADY DRILLED. TOGETHER WITH DIA #1A QC GRAM AND INSTRUCTIONS «piU.I70 FIER, for either of above eircuits, $11 Q0 ALUMINUM LOUD SPEAKING HORN, nickel plated, high polish, list $8.00 *|-Z5 3000 OHM TELEPHONE HEADSET, list $8.00 •••• • •• •• • •• • •.: •■/• l" *-4u AUDIO-FREO.UENCY TRANSFORMER, designed tor use with W. D. II tube, also excellent »r all other tubes, list $4.50 H? VARIOCOUPLER, Litz wire wound secondary. 150-600 meters, list $4.50... "•» Triple Coil Mounting $3.35 Double Coil Mounting f-*» Multiple Point Inductance Switch with knob and dial (15 points) J-*0 Reinertz coil, increased wave length ' 55 Honeycomb coil, mounted 50 turns $0.95 Honeycomb coil, mounted 75 turns 1.00 Freshman var. grid leak and cond -75 Freshman variable grid leak 60 V. T. Socket .40 CONDENSERS 3 Plate Variable, value $1.75 .$1.05 13 Plate Variable, value 2.50 1.20 23 Plate Variable, value 3.50 1.35 43 Plate Variable, value 4.50 1.95 13 Plate Vernier, value $5.50 3.75 23 Plate Vernier, value 6.00 4.00 43 Plate Vernier, value 6.50 4.25 Ball bearing inductance switch.... .25 Single circuit Jack, list 65c 30 Double circuit Jack, list 90c....... ............ .« Lightning arrester, approved by underwriters... .90 3" dials, high finish, heat resisting 30 2" dials, high finish, at 2| Filament rheostat, 6 ohms 65 Filament rheostat, 20 ohms »0 Filament rheostat, 50 ohms. .................. .90 Rheostats with 2" dial, 15c extra Every article we sell is guaranteed by the manufacturer and us— Mail orders filled immediately —Postage prepaid on all orders of $5.00 or more. east of the Mississippi River only. All others include postage.