WITH REDeDOT LIFETIMEGUARANTEED INSTRUMENT

NEW Testing Method Is Involved inThis Tester. The metal contacts

and the instrument parts are removeda minimum of one inch from the sidesof the case. The prods attached to testleads are inserted through holes in thetop panel to the contacts in the sub-panel beneath. Test leads are threefeet long and have been tested to25,000 volts breakdown. Posts are pro-vided on the panel for grounding themetal case, the surest precautionagainst bodily injury at the high volt-age. Case is enameled a solid red toindicate caution.

Tests AC and DC Volts in steps of2,500 and 10,000 volts; DC Micro-amperes in steps of 50, 500 and 5000.Meter Sensitivity-25,000 ohms per

volt for DC, 5000 ohms per volt for AC.

Model 1280-fumished with cover to matchcase and has strap handle . . Completewith accessories . . .Dealer Net Price ........$.. ... $31.50

I The Triplett Electrical Instrument Co. |218 Harmon Ave., Bluffton, Ohio

. ...... Please send me more information on IMlodel 1280: ... I am also interestedinm

I .................................. I...................................NName ......................................

I Address .................................... II City State |

vi

Current LiteratureNew books of interest to engi-

neers in radio and allied fields-from the publishers' announce-ments.

A copy of each book marked withan asterisk (*) has been submittedto the Editors for possible reviewin a future issue of the Proceedingsof the I. R. E.* IONS, ELECTRONS, AND IONIZING

RADIATIONS, Seventh Edition. By JAMESARNOLD CROWTHER, Professor of Physics,University of Reading. New York: Long-mans, Green & Company, February, 1939.xii+341+6 index pages, illustrated,5- X82 inches, cloth. $4.00.

* PRACTICAL TELEVISION BY RCA. ByService Division, RCA ManufacturingCompany, Inc. Camden: RCA Manufac-turing Company, Inc., June, 1939, 40pages, illustrated, 821X11 inches. paper.$0.25.

Booklets, Catalogsand PamphletsThe following commercial literature has

been received by the Institute.

CONDENSERS' I I Solar ManufacturingCorporation, Bayonne, New Jersey. Catalog10, 32 pages+cover, 82 Xll inches. Specifi-cations on power-type and tuning con-densers.NICKEL * International Nickel Com-pany, 67 Wall Street, New York, New York.Folder, 6 pages, 8 Xll inches. Technicaldata on rolled nickel, monel, and otherhigh-nickel alloys.TRANSFORMERS . . . Jefferson ElectricCompany, Bellwood, Illinois. Catalog 391-R16 pages, 8i X 10 inches. Power and circuit-coupling transformers for broadcast,public-address, and television-receiver ser-vice.TRANSMISSION LINES . . . Isolantite, Inc.,233 Broadway, New York, New York. Bul-letin 101-C, 2 pages, 8JXll inches. Specifi-cations on copper coaxial transmissionlines and fittings. Outside diameters of1s, 2a, and 28 inches.TUBE DATA (RCA) . . . RCA Manufactur-ing Company, Inc., Harrison, New Jersey.Application Note No. 104, 8 pages, 8j X 11inches. 'A Television Bibliography andRMA Standards," covering recent techni-cal papers and books on television engin-eering.TuBE DATA (RCA) RCA Manufactur-ing Company, Inc., Harrison, New Jersey.Application Notes Index, 3 pages, 82 X11inches. An index covering all applicationnotes since the first issue in 1933.TUBE DATA (TUNG-SOL) * I I Tung-solLamp Works, Inc., Newark, New Jersey.Bulletin 39-4, 8 pages, 51 X82 inches."Notes on the Applications of 35Z5GTand 45Z5GT," These tubes are designedfor service as combined power rectifiersand pilot-lamp ballast resistors in re-ceivers using 150 milliampere series-oper-ated heaters.

B L I LE YCRYSTALS

HOLDERSOVENS

ONLY carefully selected BrazilianQuartz is used in the manufacture

of Bliley General Communication Fre-quency Crystals. As each individual crys-

tal passes through its various processingoperations, many optical, mechanicaland electrical examinations are appliedto insure the highest possible standardsof precision and quality.So that proper characteristics and

frequency accuracy can be guaranteed,each crystal is finally checked and cali-brated in the holder in which it willoperate. Bliley crystal holders and oven

mountings are engineered particularlyfor dependable performance of BlileyCrystals from 20kc. to 30mc. Varioustypes are available to suit frequencycontrol requirements throughout thecomplete crystal frequency range.

A competent engineering staff is main-tained for product research and develop-ment. Recommendations and quotationscovering quartz crystals for any stand-ard or special applications will gladly beextended without obligation. Write forcatalog G-10 describing Bliley GeneralCommunication Frequency Crystals.

Auiguist, 1939 Proceedings of the 1. R E.