Radio mirror (Jan-Oct 1923)

May 19, RADIO DIGEST Making a Three Tube Reflex De Luxe Receiver Part III — Details of Wiring THE COMPACTNESS Of the Reflex Do Luxe makes it ideal tor automobile or motor boat installation and will help make your summer recreation trips a real pleasure. A good loop or an aerial stretched between two trees with a natural {-round. Is all that is necessary for good reception. The storage battery in the car or boat will light the tubes and the plate battery takes but little room. Importance of Proper WiringJust to emphasize the importance of careful wiring, it might be wise to relate the writer's experience with the first Reflex De Luxe Cabinet Set. The experimental circuit was first developed by means of apparatus mounted on a flat board. The wiring appeared to be a bewildering entanglement but strange to relate no inductive interference was encountered. When the cabinet set was assembled, it had to be done in very limited time. For this reason the wiring was hurriedly done, but not carelessly soldered. Insufficient attention however was paid to the alignment of the various leads. Fortunately no "bugs" were present at the first test. After all the battery connections, plus loud speaker and loop, were made the filament rheostats were turned. The ungodly collection of shrieks, groans, howls, squeals, grunts, whistles, etc., that issued from the horn, reminded one of Armistice Day, New Years, Fourth of July and St. Patrick's Day celebrations all confined in one room! Fearing ejection from the apartment, considering the hour, further testing was postponed. The next night, after three vain hours of attempts at straightening out matters, it was decided to entirely rewire the set and take a whole lot more care in aligning the leads and making the connections. Transformer Interference Both of the R.F. transformers are over A.F. transformers. In order to avoid the possibility of magnetic influence from the audio transformers, the Radio transformers were raised %-inch above the subpanel. This was accomplished by taking some fiber tubing iV-inch inside diameter J^-inch wall and cutting off four pieces %-inch long. These spacers were then inserted on the four transformer mounting screws between the base and the subpanel. The space between was found sufficient to avoid interference. Classification of Leads In order . to keep track of interference possibilities, the leads for connecting apparatus can be classified as follows in the order of their importance: 1. Grid Leads. 2. Plate Leads. 3. Secondary By-pass Leads. 4. Primary By-pass Leads. 5. Negative "A" Battery Leads. 6. Remaining Leads. The grid and plate leads should be WD 1 1 Hook-Up positively free of body capacity also giving selectivity, sensitivity and record distance, postpaid for 25 cents, or complete set of parts for $13.50. C. W. KAUTZ Box No. 362 Lancaster, Pa. By H. J. Marx added first keeping them absolutely as short as possible, and well separated from each other unless crossing at right angles. The secondary and primary by-pass leads will have to be added in conjunction with the A battery leads, since the secondary by-pass runs to the negative A and the primary by-pass to the positive A. The remaining leads can then be added avoiding proximity and parallel runs to the grid and plate leads as much as possible. /T REFLEX Erla Reflex Transformers DEALERS: SEND FOR LITERATURE ==^V TFimmzi 123 W. Mad iron St, Chicago Identification of Apparatus In Part II. Figure 2, the sub-panel layout, the tube socket in the lower left hand corner is for the first tube in the GUARANTEED VACUUM TUBES V/2 Volt Detectors $3.95 Vh Volt Detectors and Amplifiers 4.95 6 Volt Detectors and Amplifiers 3.25 Above Tubes shipped prepaid WE REPAIR YOUR BURNT VACUUM TUBES Quick Service WD-11 $3 JO UV-201-A UV-200 Z.75 UV-201 .. OUT . . .$3.50 ... 3.00 When sending Tubes for repair include with your remittance parcel postage for one pound. Tubes guaranteed equal to new. Abalene Radio 416 D Broadway New York, N. Y. circuit, the one above and a little to thai right is for the second stage. The sockef on the right side is for the separate aud:< frequency amplifier tube. (Continued on page 14) MULTIPOINT (-Patent Pending) A Synthetic CRYSTAL DETECTOR sensitive over its entire surface Eliminates all detector troubles. Extraordinary clearnetB and volume. Endorsed by Radio experts and press. Sold in Sealed Packages only. Join the ever increasing Busonite fans. Price mounted, Sensi Cfl/» tiveness guaranteed Ovt RUSONITE CATWHISKER 14 Karat Gold Multiple Contact Super OEL» Sensitive £t\J\* Order from your dealer or direct from us. RUSONITE PRODUCTS CORP. 19 Park Row. N. Y. f THE POPULAR ELGIN BOOK CONDENSER Variable — Vernier STANDARD EQUIPMENT IN ALL ELGIN HOOK-UPS We recommend this wonderfully efficient and compact condenser for the following ADVANTAGES 1st. Vernier All the Way. Three turns required from maximum to minimum capacity, instead of the customary half turn. 2nd. No Hand Capacity, if the plate nearest the hand is connected to the grounded, or dead side as we direct. 3rd. Cannot Become Shorted by metallic dust or by warping due to temperature changes. 4th. No Sliding Contacts to cause noise or trouble. 5th. Saves Space. Lies flat and requires but a fraction of an inch back of the panel. 6th. Rugged and Substantial. Heavy phosphur bronze bending leaf. Nothing to break or wear out. 7th. Reasonable Price. About one-third the cost of a vernier rotary plate. Giving the hook-up of the Famous Elgin-Reinartz Set. ELGIN RADIO SUPPLY CO. 207 E. CHICAGO STREET ELGIN, ILLINOIS =^\ Price $1.50 Send for Free Circular J Flewelling— Kaufman —Reflex— Ultra Reinartz —Neutrodyne and other circuits are greatly improved by using "MICON" TESTED MICA CONDENSERS Endorsed not only by experts, but by dealers, amateurs — in fact, every one interested in radio. Because The design of "Micons" is such that constant equal pressure is exerted on the condenser plates over the entire area. "Micons" assure absolute noiselessness, clarity of tone, accuracy, constant fixed capacity. "Micons" are invaluable as a protection against damage to the filament and their consequential short life. .006 Micon $1.00 .005 Micon 75 .001 Micon 40 .00005 .00025 . .00035 .0005 .. 30c .0015 40o .01 .. 35c .002 40c .015 .. 35c .0025 50c .02 .. 35c .003 60c .025 ., $1.50 . . . . 2.00 2.50 3.00 Ask for FREE Diagram of KAUFMAN CIRCUIT AT YOUR DEALERS — Otherwise send purchase price and you will be supplied postpaid. ffIas.Fi jshmanfo.lnc. Condenser s&oducts 106 Seventh Ave. New York Home of Freshman Variable Resistance Leaks Ask for FREE Diagram of FLEWELLING CIRCUIT