New 3YA Station.

Star (Christchurch), Volume LXIV, Issue 936, 5 December 1933, Page 6

New 3YA Station.

Radio Change

Less Volume, but Better Reception. AfR E. G. SHIPLEY writes to The Editor as follows: I read with interest not unmixed with amusement, a criticism of the new radio station now testing from Gebbie’s Pass. Your correspondent laments the decreased volume from the new 3YA, but what does he expect? A transmitter situated at Gebbie’s Pass capable of providing in St Albans the same held strength as that provided by the present 3YA would have to be several times more powerful than a mere 2500 watts, the rating of the new 3YA. Your correspondent further suggests that when transmissions take place irom the studio they will be louder. This, however, will not be so. Listeners cannot expect any more volume from the studio than as at present because the volume of transmission has nothing whatever to do with the situation of the studio, and depends only on the amount of energy put into the air by the transmitter proper. Ever since the power to be used by the new station has been made known, highpressure radio • salesmen have been loud in their disparagement of the small radio set, and many of the public have invested in expensive multi-valve receivers under the impression that such would be essential for distant reception when the new “ highpower station ” should come on the air. After the present 3YA closes down and the blanketing effect caused by having a transmitter right in the centre of a populated area disappears, the multi-valve receiver will lose much of its advantage over its smaller and less expensive brothers. Not An Experiment. The re-allocation of wave-lengths is not any experiment on the part cf the Broadcasting Board, but is the result of investigations by the board’s engineers in all parts of New Zealand during the past year. Your readers may be interested to know that radio transmissions follow what is known as the “ inverse square law.” This means that when the distance from a transmitting station is doubled, the strength of reception is a quarter. Similarly, if the distance is increased three-fold, the reception drops to a ninth. This is the reason why the new 3YA is weaker in Christchurch than the present station. At a distance of ten or fifteen miles from Christchurch, and in a north-westerly direction, the volume from both stations will most likely be about the same. The plight of the listener who lives about ten or fifteen miles in a direction towards .Gebbie’s Pass, however, must be left to the imagination. This is the man who will require the fifteen-valve receiver, not the man in St Albany. The listener who will benefit most is once again the poor old farmer; no need to have a further rise in wool; the small receiver yrill give him all the reception he requires. Various factors operate which tend to cause many departures from the law quoted above, but the nett result will certainly be a lesser volume for here in Christchurch. The increased height of the towers supporting the antenna and the probable greater efficiency cf the new apparatus will no doubt minimise to some extent the effects of the greater distance from Christchurch. In any case much improvement in reception should result; receivers which now are unable to “ cut out ” 3YA will be able to get more stations, the new station not occupying so much of the tuning scale, and, as your correspondent points out, the new wave-length is more out of the noisy part of the broadcast band. Those who lose most under the new conditions will be misguided persons who, in the- hope of dodging the visits of the radio inspector, use crystal sets with an inside antenna. One hesitates to predict the state of mind of these people after March 31 next when the B stations close down and the only means of reception from a crystal set will be per medium of the all-too-conspicucus outside aerial.