NEW YANKEE CIRCUIT

Radio Record, Volume II, Issue 6, 24 August 1928, Page 30

NEW YANKEE CIRCUIT

ROM time to time new receiving ciruits are brought out by the Ametican manufacturers. The latest i circuit brought out by a Yankee concern may be technically described as a combination of a one-control tuned, valveless band-pass filter, coupled with a startling new development in an untuned, or rather self-tuning, five valve radio frequency amplifier, which in turn passes the energy to a heavy duty detector and conventional audio frequency amplifier. Advantages claimed for the new circuit are that it-delivers full and equal sensitivity and selectivity on the. short as well as long waves;.that it does not "chop off the side bands," or, in layman terms, distort the received sound by reason of its ultra sharp selectivity, and that the radically new departure in radio frequency amplification which it employs gives approximately double the yield from the equivalent high class set of the "tuned radio frequency" class. "We can reduce 75 per cent. of the congestion in the ‘scrap heap’ section of the broadeasting channels below 300 metres, where 500 of the country’s 700 broadeasters have been assigned at present," said the manufacturer’s president. The smaller models of the sets employing the new circuit use seven radio valves. De luxe models use nine. The circuit is obtainable in both "A.C." or alternating current type, as well as battery type sets. Another advantage claimed for the circuit, viewing it from the manufacturers’ standpoint, is that it has no conflict with the Alexanderson patent, a very valuable: franchise for which many independent radio manufacturers necessarily pay heavy royalties to the Radio Corporation of America. In. addition, no "balancing" methods are employed and not one grid leak is used.in the circuit.