Radio mirror (Jan-Oct 1923)

May 5, 1923 RADIO DIGEST Making a Three Tube Reflex De Luxe Receiver Part I — Panel Layout and Hook-Up By H. J. Marx AFTER tlircp months of research work ami experimentation, there is a considerable degree of satisfaction In presenting .1 circuit that accomplishes a little more than what has been done before. Experience teaches us that rarely can we get that all-around combination of advantages continually sought, but seldom attained. Some circuits have the advantage of their good distance reception: others have volume; then again others have the disadvantage of requiring too many tubes: or, again, tuning may be complicated and difficult. In working on this circuit, it has been the aim of the author to eliminate un PARTS REQUIRED VT— 3 Hard vacuum tubes and sockets VC — Variocoupler CS — 2 Contact switches RT — 2 Radio frequency transformers, reflex type AT-1— 2 Audio frequency transformers AT-2— 1 Audio frequency transformer, high voltage type P-l— Potentiometer, 400 ohms J-l — 2 Double circuit jacks J-2 — 1 Open circuit jack J-3 — Jack type battery switch R-l— 1 Rheostat, 6 ohms R-2— 1 Power rheostat, 6 ohms R-3 — 1 Grid leak, variable C-l— Variable condenser, .0005 mfd. C-2— Variable condenser, .0005 mfd., vernier C-3— 4 Fixed condensers, .002 mfd. C-4— 1 Fixed condenser, .0015 mfd. C-5 — 2 Fixed condensers, .006 mfd. CD— Crystal detector Eight binding posts One panel, 9x1 2s ,x.l inches One sub panel, SVaxllVixtk inches One cabinet, 7 inches inside depth 25 Ft. tinned bus bar wire 20 Ft. spaghetti tubing necessary controls, reduce so far as possible not only the quantity of apparatus but also the number of necessary adjustments. After the circuit development was completed, then arose the problem of compact assembly on the panel and in the cabinet. This required time and patience, but was worth the effort. Not Low-Priced Outfit The Reflex De Luxe cannot be considered a low-priced outfit, but its cost is low when its possibilities are considered. The no hesitation in the use of this circuit with either type of receiving antenna. The antenna and ground connections can be made direct to the binding posts, whereas the loop can be plugged in on a jack, automatically cutting out the var.iocoupler tuning unit. In addition, if the two contact switches are turned so the lever on each one rests on contact 15, the circuit can be operated as a single cir iATTEOT SWITCH volume with three tubes has been sufficient to make the diaphragms of the best of loud speakers chatter, and one of the chief difficulties was in getting sufficient control over its volume without loss of the good quality of the reception. The circuit has been arranged for use with both outdoor and loop aerials. Experimental work has been conducted entirely with the use of a loop aerial. Inasmuch as an outdoor antenna is unquestionably more efficient, there need be CARTER RESISTANCE UNIT By placing this Resistance Unit in the Rheostat circuit, regular 6 ohm Rheostats will properly operate the new No. 201-A and No. 199 Tubes. Each Code No. 15-A, 15 ohm, for No. 201-A Tube.. 50c Code No. 25-A, 25 ohm, for No. 199 Tube 50c Write for bulletins on this and other Carter products CARTER RADIO COMPANY 209 South State Street. Chicago cuit tuner, using the primary and secondary condensers for tuning controls, or by switching just one of the contact I7D1717 VACUUM TUBE^' ftCEfEi RADIO SET The Set you always Wanted, FREE ii:t,cive i J RUSH A real RADIO SET— Listen in on Concerts. Lectures, Singing, etc. Can _receiye_75 to 100 miles and more. [ your name and address and we will tell you HOW you can get a I VACUUM TUBE RADIO SET ABSOLUTELY FREE Don't delay. Write today for FREE RADIO PLAN. Home Supply Co. Dept. 457 131 Duane St.. New York BETTER LOUD SPEAKERS $9.85 3 ^fck" T.T„T" ?:?? TRUE CABINET TYPE, like the finest i-^9n modern phonographs, with all their beauty V/3% ^Hi and perfect tone. Makes your two-step set a real ENTERftyH TAIXER for family and friends. SPIROLA DUPLEX uses any Vg ^B headset. SPIROLA SIMPLEX uses Baldwin or other unit. ^^^^T Either type, black with nickeled fittings, $3.85; mahogany finish with bronzed throat, $4.85. At dealers or postpaid (C. O. D. if preferred). Absolutely guaranteed. T„ H. DOXNELI, MEG. COMPANY. Dent. T). Box 70. ANN ARBOH MICH. switches to 15, a different arrangement is provided. Circuit Inverse Keflex The circuit used in this set is not only reflex, but also utilizes the inverse ar rangement which both Priest and Grimes found to show great possibilities for development. Various changes have been made after trial in an effort to incor(Continued on Page 14) WILLARD WILLARD RADIO COMPANY Dept. R. D., 291 Broadway, New York City "The Best for Less" FLEWELLING CIRCUIT EVERY PART COMPLETE 2 honeycomb coils. 1 2-coil mounting, 2 coil plugs, 3 .006 condensers, 1 variable grid leak, 1 grid leak, 1 23-plate .0005 MFD. variable condenser. 1 Vernier rheostat. 1 tube socket, "8 binding posts, M feet bus bar wire, 1 high-grade panel ALREADY DRILLED AS PER DIAGRAM, 1 3" dial and the Radio Digest Booklet on Operation and Construction of Circuit $11.00 Two-Stage Radio Frequency Amplifier — Parts complete in every detail for this Circuit— $11.00. CONDENSERS 3 Plate Variable; value, $1.75 13 Plate Variable; value, $2.50 23 Plate Variable; value, $3.50 43 Plate Variable; value, $4.50.... .$1.05 . 1.20 . 1.35 . 1.85 13 Plate VERNIER: value, $5.50 3.75 23 Plate VERNIER; value. $6.00 4.00 43 Plate VERNIER; value, $6.50 4.25 VARIOCOUPLER — Celeron Condensite and Litz Wire Wound Secondary; Value $4.50. Special $3.95 AUDIO FREQUENCY TRANSFORMER — Designed for use with W. D. 11 Tubes, list, $4.50; price $2.75 Honeycomb Coils, 50 turns mounted . $0.95 Honeycomb Coils, "5 turns mounted. LOO Double Coil Mountings 2.45 Triple Coil Mountings 3.35 Reinartz Coils and Mounting . 1.75 BALL BEARING INDUCTANCE SWITCH — value 75c, special $0.30 V. T. SOCKETS — Nickeled, brass sleeve, composition base value, $1.00; special at.. .50 EXTRA SPECIAL— Telephone 3000 Ohms Headsets; $9.00 value: reduced to $3.50 ALUMINUM LOUD SPEAKING HORN— Nickel plated, highly polished; $8.00 list $3.75 A BEAUTIFUL "SALRITE" PENCIL FREE SALRITE C'".«.ms».?r l! !<! TO* With every order of $12.50 or more. Made of beautiful Mahoganite Rubber, about five inches long. Equipped with vest pocket clip, 10 extra leads and eraser. Will write like a ciarm and last a lifetime. Only a limited supply available — so rush your order now. BEST QUALITY JACKS. Single Circuit; value, 65c; special at 30 Double Circuit; value, 90c; special at 45 MULTIPLE POINT INDUCTANCE SWITCH with Knob and Dial (15 switch Points) 1.75 LIGHTNING ARRESTERS approved by underwriters $0.90 THREE-INCH DIALS — Unbreakable — heat resisting composition — high finish; special. .$0.30 TWO-INCH DIALS — Same design— for rheostats and potentiometer; special at $0.25 FILAMENT RHEOSTAT— Condensite base; value. $1.10; special at 70 FILAMENT RHEOSTAT with 2'/a" dial; value, $1.50; special at TELEPHONE PLUGS FRESHMAN VARIABLE RESISTANCE LEAK and MICON CONDENSER Combined .75 REINARTZ CIRCUIT EVERY PART COMPLETE 1 Reinartz wound coil, 1 tube socket, 1 rheostat. 1 23-plate .0005 MFD. variable condenser, 1-13-plate .00025 MFD. variable condenser, 3 inductance switches, lfi switch points and nuts, 4 switch stops and nuts, 8 binding posts, 2 3" dials, 1 variable grid leak, 1 .002 MFD. phone condenser, 23 feet bus bar. Hire, 1 high-grade panel ALREADY DRILLED AS PER DIAGRAM and complete Instructions Two-Stage Radio Frernienry Amplifier — Parts complete in every detail for this Circuit — $11.00. Every article advertised above is guaranteed by the manufacturer and by us — Mail orders filled immediately— transportation PREPAID on all orders of $5.00 or over east of the Mississippi River. All others include postage. JL ™