The Birmingham age-herald., 1924-11-16
UNSEEN TRICKS
 OFTEN PLAYED ON THE UNWARY
One Man Tried Six Sets And Seventh Worked;
 Why?
BY C. D. TUSKA

There are plenty Ot fallacleS Tn the world which we can hardly avoid, so let us recognize number of avoldable radio fallacies. These fallacies are so obvious to the experienced that the situation is even comical at times. It seems too bad that the public, whlch after all, is the backbone of radio should be received either intentionally or unintentionally.
 Radio is the one science, hobby or sport which has so many outside intlu- ences that it very hard to see clearly from all angles. We buy radio set and take it home. It works splendidly one night. The next night it puts up the most terrible exhibition which hu- <. man ingenuity can devise. The set works perfectly before the company ar rives, then stops completely and returns to it's good graces as soon as the com pany goes home. What will you blame it on? About the only thing that the average person can suspect Is the radio itself. Is this always the case? Nine ty-five times out of a hundred the answer is "No."
 Just as an example of what tricks can be played on us, I go back to my radio experience of last night and the evening before. I started to listen about ' o'clock and the results were wretched At 8 o'clock the results were fair, at o'clock very good; about 9 80 I was getting splendid results. This happened on two evenings. The stor- age batteries, tubes and set remained exactly the same. The only thing that changed was the radio weather. Blam- ing the radio set in case of this sort is a fallacy. We should not blame the set, but the ether.
 Tried Six Sets
 Not long ago I heard of a man who took six sets home. Not a single one of the six would work. On the other hand he had a set which looked sim liar to all the others and this set did work In all seven the batteries, tubes, loud speaker. and aerial were the same. He blamed the only thing that he could think of blaming-the sets and working them one right after the other in a diff ferent location with perfect results.
 What was the fallacy of blaming the sets? The six sets had a certain type of aerial coupling which would only operate on medium length 'aerials. The seventh set was coupled in such a way that it would operate with all most any antenna. The antenna that he was trying to use was over 250 feet in length and it was clearly out of the class which should be connect ed to the six receiving sets.
 Nowadays the prospective purchaser of a radio receiver asks: How many tubes has it?" If the salesman says five and the price is $50 the prospec tive purchaser thinks that this set must be better than some other outfit which has four tubes. On the other hand, if the saleman says six tubes and $150, then the customer is sure that the six tube outfit must be be better than the fiye-tube, and in addition he decides that it is more for the money.
 F This kind of reasoning is exactly an- alogous to judging the value of an au- tomobile and its performance purely on . a basis of the number of cylinders in the motor. If the motor has four cyl finders then all four-cylinder cars will do about the same thing and are sold at about the same price! All six-cylin- der cars would give the same perform ance and are worth about the same : |, The eight-cylinder motors would be be- yond competition from the smaller num- Der of cylinder cars! The minute we begin talk in these terms about auto mobiles you can see the fallacy in the reasoning. l know a number of four cylinder cars which would out-diStance some small six-cylinder ones and I have observed a number of six-cylinder cars which are superior to anything in their class. It may be dangerous to carry this analogy too far because we all have our prejudices regarding motor cars.
 Careful Test
 In order to touch, mathematically, on the number of tubes" fallacy I am going to point out that a certain set was designed and tested with a great deal of care by people well qualified to make such an experiment. This set employed one radio frequentcy amplifi- CT. Due to the presence of a consid- erable amount of regeneration, the vol tage amplifieation in this one tube ex- ceeded one hundred timeS the incoming signals that is, if the incoming signal was unity the simplifying signal was 100 times unity. In some of the recent five tubes sets employing two stages of ra- dio frequency we get an amplification factor of the tube. There is supposed - to be no regeneration present and gen erally there isn't very much. This gives an amplification from nine to ten dimes that result in the second stage.