Radio age (May 1922-Dec 1923)

16 RADIO AGE— "THE MAGAZINE OF THE HOUR" Suminer Static and How to Meet It SAY "static" to a radio enthusiast and listen to what he says, or else cover your ears. His opinion of the greatest nuisance which besets radio telegraphy and telephony will no doubt be fervent if he is an experienced operator. If he is an amateur, it will be despairing. When a radio fan talks of "static" he means the small charges of positive electricity which infest the atmosphere, forever seeking an outlet to the negative earth. They are in effect miniature bolts of lightning which have not the force to strike under their own power. Hence they seek assistance, which is unwittingly extended to them by the aerial of the radio apparatus. By means of this they find a ready passage to the ground, where they cease to be troublesome. But woe to the amateur whose aerial is not well "grounded." Balked of their goal, static charges have been known to start fires. Even greater is the danger during a thunderstorm, unless a good grovind wire is provided. Any ground installation which complies with the underwriters' requirements will furnish adequate protection, however, against this. It is always advisable to stay away from wireless apparatus during a storm. Commencing with the next few weeks, radio operators and amateurs will encounter static with increasing frequency due to the approach of warm weather. Static is more abundant in summer than at any other time of the year, making it extremely difficult for the average radio enthusiast to operate his set. The cause of this trouble is sometimes in the use of an aerial that is too lengthy. No aerial for receiving broadcasts should be more than 150 feet in length. Where a two-wire type is u.sed, the length, including the lead-in wire should not exceed sixtyfive feet. Where a station is located near a broadcasting center, indoor aerials will be found superior in summer. These may be made in the form of a grid or coil, either mounted on an insulated stand, or attached to porcelain insulators fixed in the beams of the attic of the house. This device is only for use in houses where metal roofing is not employed. All wires must be kept as far as possible from the lighting system wires of the house. Vacuum tubes are imperative in using this type of aerial, but their expense is offset by the resultant freedom from static. THE WIRELESS CODE 1. A dash is equal to three dots. 2. The space between parts of the same letter is equal to one dot. 3. The space between two letters is equal to three dots. 4. The space between two words is equal to five dots A* Mi ^ ■■ • • • Dm** E* F • • Hi * H**** I** L • 1^ • • N ^* P * Mi ■■ * R* iM* S * * * U**H V* • AM X ■■ • • HI z ■■ ^ * • Period...; •• • Semicolon ^m • ■ Comma • ^m • Colon i^ ^ Interrogation • • ik Exclamation point ^ h* Apostrophe • hh ■ Hjphen ^ • • Bar indicating fraction ■■ • • Parenthesis i^ • ■ Inverted commas • ^ • Underline Double dash Distress CalJ • • ^ I • • • ■■ Attention call to precede every transmission -' General inquiry call From (de) Invitatitn to transmit (go ahead ] A (German) 1 • ^ ^ ^ ^ « ^ « wm ^ *" A or A (SpBoish-SraodioaviaD) 4 • * * • « CH (German-Spanish) 6 ^ • • • * ^ (French) • • ■■ * * ^ ^ ^ • • • N (Spanish) 9 ^ HH wa BH • O (German) t) (German) Warning— high power Question (please repeat after ) — interrupting loag messages Wait , Break (Bb.) (double dash) Understand Error Received (O. K.l . Position report (to precede all position mes. sages) End of each message (cross) Transmission fiDishcd (end of work) (conclusiOB of correspondence] The curious fact that so-called "airpockets," impenetrable to wireless telegraph or telephone waves, exist in the atmosphere was commented on recently by F. B. Chambers, a Philadelphia authority on radio matters. "There are three well-known 'pockets' here in the east," said Mr. Chambers. "One is near Pittsburgh, another somewhat north of New York city, and the third in the gulf of Mexico. "The Pittsburgh one covers an area about a mile and a half square. The New York one is the largest, being fifty miles in extent. Many theories are offered to account for these strange phenomena. The most plausible one is that there are certain strata of minerals underlying them which deflect the wireless waves off at a large angle. The question of their origin, though, has never been satisfactorily solved." — Philadelphia No. American. Learning the Code A practical method devised for mastering the code at home is to be found in the set of six Victor-Marconi records which reproduce on the phonograph the international Morse Code characters exactly as they are heard by wireless. There are twelve lessons, which carry one from the novice to the expert stage. National observers say that new radio factories have helped take the edge off the unemployment situation. River Affects Waves Fletcher H. Hiles of Cincinnati, a steward on the Big Four limited, running between Cincinnati and Cleveland, is perfecting a system of intercommunication between trains by means of radio telephony. He has been picking up concerts, also, while the trains are at top speed. At points where the track parallels a river the receiving is fine, but goes dead when the tracks are at right angles with the river.