Radio Broadcast (May 1928-Apr 1929)

.RADIO BROADCAST ADVERTISER. 37 Australia to New York-— Verified. Reception done— of course— with an S-M Receiver! The great Sargent-Rayment 710 — aptly termed "The Boss of the Air." Everything the most fastidious listener might want — an ultra-sensitive and knife-edge tuning set, which can, nevertheless, be operated when desired as a real one-dial set — with tone quality unsurpassed even in sets not designed for unusual selectivity. All this at $130.00 for the KIT, or $175.00 WIRED— both prices including cabinet! We are in receipt of your letter, undated, and have pleasure in confirming the items mentioned by you as having been broadcast by this station. We are always glad to hear from over the seas , and hope tohear from you again vrith regard to our transmission AUSTRALIA to New York City on .^V. 353 meters! Direct verification from Station 2BL in Sydney, New South Wales, to a listener by the Hudson— one of the many thousands who have successfully employed the S-M Sargent-Rayment Seven to break through congested local interference. We congratulate Mr. Parzelt on this feat of reception, and are happy to be able to supply, to all who desire it, a receiver of such caliber. Second only to the Sargent-Rayment, and nearly as famous for its distance records — including reception from Japan in many parts of the U. S. — the S-M 720 Screen-Grid Six brings surpassing radio quality within the moderate-priced range. It contains the same matchless S-M Clough-systcm audio transformers. KIT $72.50; beautiful metal shielding cabinet extra $9.25. WIRED complete in cabinet, $102.00. 23. 1-. Service Mr. tfllliam Parzelt. 128 Poet Avenue, lev York City, U.S.A. Now a Speaker Made as Good as S-M Amplifiers The S-M Dynamic Speaker, now announced for the 6rst time, establishes still more firmly the superiority of S-M sound amplifying equipment— a speaker supreme in its ability to handle without distortion an amazingly large amount of power. Has the new S-M 229 output transformer built in, with output taps providing proper impedance matching for use with 171, 250, or the new intermediate power tubes, singly or in pushpull. Two types: S-M 850, for 110 volts A. C. (using '80 rectifier tube) $58.50. S-M 851, for 110 volts D. C, $48.50. Giant Voiced ^ Yet Pure -Toned Never before has such an amplifier as the S-M 690 been available to the setbuilder and service man! It brings within his control installation jobs in theatres, auditoriums, and for all public occasions. The public, thoroughly awakened by the talking-movie, is demanding life-like high-power sound amplification where formerly ears were strained to "catch the high spots." Find out today about the remarkable things that can be done with an amplifier delivering such tremendous power output as 15.000 miliwatts — from phonograph, microphone, or radio-detector input — with three-point switch on the panel, as well as a knob giving smooth fading control whatever input is being taken. S-M 690 Amplifier is built on a black crackle-finished heavy aluminum panel 12x21 inches. Uses seven tubes: 1st stage, one '26; 2nd stage, two '27's in push-pull; 3rd stage two '50's in pushpull; two '81 rectifiers. All power from 110-volt A. C. socket. List price, assembled complete less tubes, $245. And the S-M 678PD — powerful enough for small theatres and almost any dance hall, yet priced so low as to be ideal for the home also — supplies, by use of the S-M Clough audio system, the full undistorted power of a '50 type tube to any 110-volt D. C. dynamic speaker; supplies field current also. All power taken from 110-volt A. C. light socket. Price WIRED $73; complete KIT $65. Get the new S-M catalog — and begin today to look about you for the opportunities that exist everywhere to make good money by installing S-M amplifiers. The Radiobuilder, a monthly publication telling the very latest developments of the S-M laboratories, is too valuable for any setbuilder to be without. No. 9 (Jan. 1929) gave full particulars about the new apparatus described above, long before it was available in any other form. Send the coupon for free sample copy, or to enter your subscription if you want it regularly. If you build professionally, but do not have as yet the S-M Authorized Service Station appointment, ask about it. SILVER-MARSHALL, Inc. 838 West Jackson Blvd., Chicago, U. S. A. Silver-Marshall, Inc. 838 W Jackson Blvd., Chicago, U. S. A. ....Please send me, free, the complete S-M Catalog; also sample copy of The Radiobuilder. For enclosed in stamps, send me the f ollowing: . . 50c Next 12 issues of The Radioouilder .. SI .00 Next 25 issues of The Radiobuilder S-M DATA SHEETS asf ollows, at 2c each: . .No. 1 .670B. 670ABC Reservoir Power Units . .No. 2. 685 Public Address Unipac ..No. 3. 730. 731, 732 "Round-theWorld" Short Wave Sets ..No. 4. 223. 225. 226. 256. 251 Audio Transf ormers . .No. 5. 720 Screen Grid Six Receiver . .No. 6. ' 40"Coast-to-Coast" Screen Grid Four . .No. 7.675ABC HighVoltage Power Supply and 676 Dynamic Speaker Amplifier . .No. 8. Sargent-Rayment Seven . .No. 9. 678PD Phonograph Amplifier n • march, 1929 page 287 •