IN THIS ISSUE -NEW! FM Station I o List C ILA HUGO GERHSBACK, Editor BRUNETTI WRIST-WATCH TRANSMITTER SEE PAGE 28 SALES of previous editions offer the best evidence of its worth. Edition Year Copies sold 1st 1937 51,000 2nd 1938 25,000 3rd 1939 55,000 4th 1941 60,000 5th 1946 75,000 Here's what you get: Data on correct replace- ment parts Circuit information Servicing hints Installation notes IF peaks Tube complements and number of tubes References to Rider, giving Ready April 1st volume and page number RESERVE YOUR The 6th Edition COPY NOW Mallory Radio Service Encyclopedia Here it is -up to date -the only accurate, authorita- number of tubes ... and in addition, cross -index to tive radio service engineers guide, complete in one Rider by volume and page number for easy reference. GIVES YOU ALL THIS IN- volume -the Mallory Radio Service Encyclopedia, NO OTHER BOOK FORMATION- that's why it's a MUST for every 6th Edition. radio service engineer. Made up in the same easy -to -use form that proved 25% more listings than the 5th Edition. Our ability so popular in the 5th Edition, it gives you the to supply these books is taxed to the limit. The only complete facts on servicing all pre -war and post -war way of being sure that you will get your copy quickly sets ... volume and tone controls, capacitors, and is to order a copy today. Your Mallory Distributor vibrators ... circuit information, servicing hints, will reserve one for you. The cost to you is $2.00 net. installation notes, IF peaks, tube complements and It's the buy of the year. THE MALLORY RADIO SERVICE ENCYCLOPEDIA Complete -Authoritative -All in One Volume O . VIBRATORS SWITCHES ... RESISTORS ... RECTIFIERS ... VIBRAPACK` POWER SUPPLIES . FILTERS ALLOR 11.9. U. S. Pol. Off. APPROD PRECISION PRODUCTS P. R. MALLORY & CO., Inc., INDIANAPOLIS 6, INDIANA Building tits A. M. SIGNAL GENERATOR gives you valuable experience. Provides amplitude modulated sig- nals for test and experiment pur- poses. RADIO SERVICING pays good money for full-time work. Many others make $5, $10 a week EXTRA fixing Radios in spare time. VETERANS You can get this training right in your own home under G. I. Bill. Mail coupon for full details. a RADIOgpare Time tea ri'r -JI PRA #6111"1 with Big Kits You build this SUPERHETERO. of Radio Part si Send You DYNE CIRCUIT that brings in local and distant stations. You get Do you want a good -pay job in Radio -or your practical experience putting this own money- making Radio Shop? Mail Coupon for set through fascinating tests. a FREE Sample Lesson and my FREE 64 -page book, "How to Be a Success in RADIO -Television, You build this gives you practical MEASURING INSTRUMENT Electronics." See how N.R.I. 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INu salesman will call. fleas° write plainly.) J. F. Smith, President, Dept. BDX. National Radio Institute, 1'I,ß+, t o r /tom r Study Radio Srhnol. Washington 9, D. C. Name My Course Includes Training in Address City TELEVISION * ELECTRONICS Check If Vetaran Frequency Modulation APPROVED FOR'TRAINING RADIO- [RAFT, April. 1948, Volume XIX, No. 7. Published monthly by ltadcraft Publications, Inc.. 29 Worthington Street, Springfield 8, FLU. tittered as second class matter at Post Office, Springfield, 81ass., under the Mt of \larch 3. 1879. RADIO -CRAFT for APRIL. I94f UNION the NATIONAL TRIPLE-AID PLA to the TOWN BUSIEST SHOP IN E,DSIHES - SERVICE BISSER BIIILD ß 1Il1 D E RS HU BUSINE55 DjS I H ESS N U are plImoica teitillk pieces BUILDERS promotion service $evicc, Window Decals tiyYON At'th4toN friendly gook Molches 9P . " your banana integrity Builders Dummy Cottons ... 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