Radio Digest (Oct 1923-July 1924)

February 9, H'J'i RADIO DIGEST — Illustrated OPERATING AND TROUBLE SHOOTING For the Owner of a OPnROB rrf Receiver THE neutrodyne receiver is essentially different from the more familiar types and the procedure to be used in tuning is also different. Tubes This set is adjusted for three 201-A tubes and one type 200. These tubes should be used in the sockets as follows: Two 201-A's in both sockets next to the panel, and one in the rear left socket; the 200 in rear right socket. Better Connections After inserting the lubes, the battery connections should be made a* indicated by the markings on the panel. Ground and antenna connections should be made except when close to transmitting station. By plugging the phones in the detector jack the set is ready to tune. Tuning" As this set does not squeal it is necessary to tune to the signal wave length rather than to the carrier wave. The two right-hand dials 2 and 3 control the wave length to which the set is tuned and these two dials tune together, For example, if it is found that one station tunes in at 45 on the second or middle dial 2, and 49 on the third or right-hand dial 3, it should be noted that there will always be a difference of four points be tween dials 2 and 3, it will be found a simple matter to tune in distant stations, by increasing or decreasing the adjustments of these two dials, one point at a time, and swinging antenna dial bark ami forth over about 10 points known to be near the correct adjustment. As soon as the station is picked up, it is a very simple matter to tune it in. (5) ® <§> © © tween these two dials. Before endeavoring to tune in a distant station, this difference should be determined on a strong local signal. Dial 1 will be found to follow dials 2 and 3, but its tuning is affected by changes in the antenna. After determining the difference be If a log is kept of the readings it will be found that the same station always comes in at the same setting, unless, of course, the transmitting wave length is changed. After the tubes have been installed, it is advisable to try different B battery volt ^C^///M4«4J^^I. Yog* prompt action gives you one bound volume with each annual sub/ scription. New or renewal* Greatest Collection of Radio Information A. B. C. Lessons for Radio Beginnxrs. Two, Three, and Four Tube Reflex Circuits. The Famous Miloplex with Various Hook-ups. Reinartz Long Distance Circuits— Ultra Reinaitz. Flewelling Popular "Fliver" Circuit. Single. Tube Reflex Circuits — Super-Heterodyne Five Tube Neutrodyne, Special R. D. Hook-ups. t In addition to these features, the current issues give you all the live news in Radio. The popular Q. and A. Department, How to Operate Youi" Set, Advance Broadcasting Stations Programs, and a correct list of all Broadcasting Stations. ■M , ■ RADIO DIGEST. 123 W. Madison St Check Offer Desired □ One year's subscription, and choice of one volume. Send Vol Enclose. . .$D.O0 □ One year's subscription, and choice of two volumes. Send Vols Enclose... 7. no Additional Bound Volumes at $2.00 each. Name CHy State. Serving as a Radio Reference Library You receive 52 issues with your Subscription and 13 issues in each bound volume Bound Volumes 3, 4, 5, and 6 now ready. Volume 7 ready about February 15. This offer good only in U. S. and Possessions, and Canada. This offer not good through dealers or subscription agencies, but must be sent us direct with the full subscription price. Remittance must be by check, money order or draft. ages and different adjustments of rheostats 4 and 5 to determine the values best suited^to the tubes used. Renewal of Tubes If the directions for operating the set are carefully observed, the vacuum tubes will have exceptionally long life. When the filament of a tttbe does burn out. however, the tube should be replaced by a new one. Use same type when ordering spare tubes or replacements. Renewal of B Batteries After B batteries have been in service from 8 to 12 months they become exhausted so that the signals are weak and disagreeable noises are produced. This condition may be remedied by replacing the battery by a new one. Possible Difficulties Anything which tends to increase resistance or decrease insulation will cause poor operation. As the batteries grow How to Take Care of the Radio A Battery Bee that thi tight and sera terminal connections going out of the battery so that they are bright and will form a contact. Bee that there is no acid or v. spilled upon the top of the battery v. would cause voltage leakat,-' cells. Keep the lop of the battery dry. Keep the pi. red with wat* all times. The solution should cone bast V* inch over the top of the pli nly distilled water. Do not permit the battery to stand i pletely discharged for any length of • it should be recha reading shows under 1,200, W charged hydrometer reading is bet 1,280 and 1,300. In using hydrometer, see that the float does not cling to the side of the glass tube. When taking reading i rubber bulb is fully expanded an<l indented, as otherwise suction would permit incorrect reading. Remember that all new batteries are somewhat like a new automobile. They do not reach their full efficiency until they been in service for a little whili new battery will, therefore, not give as Ion;,' service on a singli as it Will after it has been recharged a few times. old, they decrease in voltage and increase in resistance. As the tubes grow very old, the filaments become less effective. Each fault, however, suggests its own remedy. 1. Poor connections in antenna or ground wires or defective insulation of antenna. 2. Rheostats not properly adjusted. :!. Batteries exhausted (indicated by low filament brilliancy, weak signals and distortion), 4. Battery connections improperly made, poor or broken. 5. Tuning controls not in correct adjustment. 6. .Poor or broken connections in telephone cord or plug. 7. Inoperative vacuum tubes. 8. Glass tube resistances (grid leaks) fallen out of their mountings. NOW YOU CAN GET THEM FROM YOUR DEALER COMSCO COMSCO COMSCO CONDENSERS The most ingenious variable air condenser ever conceived No outside Spring Connections — True Capacities. and Remember the Bronze Bushings! 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