OVER THE AERIAL.

Auckland Star, Volume LVIII, Issue 88, 14 April 1927, Page 16

OVER THE AERIAL.

WIRELESS NEWS FROM FAR AND NEAR.

3-''. (By "PHONOS.")

Eastertide broadcasting was quite general last night. Auckland, Melbourne and Brisbane were all providing programmes appropriate to the season.

New Zealand is to have a new radio magazine, which will sec the light of day from Christchurch in about a month's time. Knch licensee will receive gratis a copy of the first issue.

For the benefit of those radio folk who arc keen followers of horse-racing, it may be mentioned that during the four days' carnival at Randwick, Sydney, at Easter time, 2 FC will have a special racing half hour nightly, from 6 to 6.30 p.m. New Zealand time.

3LO, Melbourne, is making thorough efforts to outdo other Australian stations in Its broadcasts of function! during the week of the Royal visit to the Victorian capital, and New Zealand listeners should have some interesting evening hours next week by tuning in the best of Australian stations.

What has become of the Broadcasting Board? Though it was supposed to meet quarterly, nothing has been heard of it for many moons, yet there arc many matters which it might well discuss, and many things concerning the conduct of radio service in New Zealand which might well be ventilated before it. A revision of the wireless regulations is one, and one in which all interests should be consulted.

The relay from the Majestic 6n Wednesday night provided quite pood items of entertainment, and last night's effort may be credited as an excellent one for IYA. The whole of a fine and appropriate musical programme came through perfectly, organ and choral effects being particularly commendable. In passing comment upon local programmes, however, it may be as well to remark that four pianoforte solos in one evening is hardly a means of satisfying the penprnl public ta*te. With the average listener a little piano music goes a very long way indeed, no matter how good it mav be.

4QG Brisbane, certainly achieved a triumph in its broadcasting of the Parliamentary reception to the Duke and Duchess last week. F.very word of his Royal Highness* speech camo through distinctly, and though there was some little hesitation on his part at the start, he was soon well into his stride. The announcer gave a vivid picture of the scene, and a breezy account of his efforts in describing; it. while a young lady with a wonderful vocabulary of superlatives gushed descriptions of the frocks—particularly of that of the Duchess. It is strange, and in no way due to lack of effort on the part of the Rroadcasting Company, that more New Zealanders heard the Duke's voice when he was in Queensland Uian did so during his trip right through New Zealand. One would like to know the real reason why the microphone was banned at functions here and yet was used in Australia.

When signals from a distant station fade, atmospheric conditions arc mainly responsible. it is unusual for local reception to vary, however, acd when it docs so a faulty H.T. battery or a poor grid condenser can be blamed. If the battery is old —say more than two months —it will probably be the culprit, but if test exonerates it from blame the grid condenser should 1» substituted If fading continues, change the gridleak also.

It is current gossip in the city at present that this year's registration* of listeners arc far short of what w»i anticipated. If this is merely due to neglect, then the activities of the departmental officers will soon remedy it, but if the failure to renew licenses is clue to disappointment with the service supplied, on the part of hundreds of thousands who have previously listened in, there is room for investigation of the whole radio situation in the Dominion, for experience elsewhere has shown that listening in, where service is good, is anything but a passing craze.

A LOUD-SPEAKER SURPRISE. The following story comes from Aus tralia: —

An affectionate wife decided to purchose for "hubby" a wircle** set, complete with loud-speaker, choosing bis birthday as an appropriate time for making the gift. During his absence she bad it installed and tuned to the local programme, so that she could switch it on when the sound of well-known footsteps announced his arrival.

This she did, and quickly retired to ber bedroom. It was unfortunato that a play was being broadcast at the time, a play in which an amorous lover was almost shouting: "You must bo mine, you darling. After the love you have shown me, after you have embraced me, after you havo showered kisses upon me, you must, I say, be mine, mine, mine!" And this is what "hubby" heard when ho opened the door. You can guess what ho did. Golf clubs, umbrellas and finally an umbrella stand were thrown into the dark drawing room. Then came a scries of crashes, followed by silence

A light revealed the set on the floor, the valves—four of them —smashed to smithereens, and the loud-speaker a crumpled mass. "Hubby" had his surprise all right. CRYSTAL AMPLIFICATION. Following on last week's notes these additional particulars on a subject of particular interest to crystal users arc supplied. Two stages of audio frequency amplification will be found to give very much increased signal strength from a crystal receiver and will quite easily work a loud-speaker within a certain distance from a broadcasting station, dependent of course on the power of the station. From IYA good loud-speaker reception, using a crystal set with two stages audio amplification, should be obtained up to a distance of about 10 miles. This, of course, is a conservative estimate, as quite a number of factors enter into this, «,uch as location, the

clficiencv of the crystal detector and the amplifier, but these need not be detailed now. When build-up up two stage* of transformer-coupled audio frequency amplification care should be taken to use only pood component parts, and not to "crowd."' It is advisable, if the transformers used are of the unshielded type to mount them at right angles to each other, so as to prevent interaction between them. This interaction seta up a very nasty howl, which is very annoying and completely spoils reception. The general practice in building up two stages is to u«c two transformers of different ratios, usually o—l and 3§ —I. The large ratio is generally used in the first stage and the smaller ratio in the second, the reason being not to "step up" the signals too abruptly and overload the last valve. as this "is likely to cause distortion, but for reception, using a crystal detector, it is better to u*e the lewer r»ti» transformer immediately following the detector, and the higher ratio last as this gives more uniform amplification. Distortion in an amplifier may be caused by improper battery connections or improper br.ttery voltages. Too low a filament voltage will not only lower the output of an amplifier but it will introduce'serious distortion It is therefore, advisable to see that the filament lighting battery of the valve* is kept up to "scratch." The high«r tht **B~ battery voltage, provided that it is within the limit* specified by the manufacturers of the valves used, the belter the reproduction both as to quality and volume Care should be taken, however, tn. see that an old "B" battery which has dropped in voltage is «ot used in series with one that is good, ns the old battery will cause crackling noises and spoil reception, as well as running down the new battery more quickly than is necessary. Sec that th- valve legs where they make contact with the socket arc kept dean. A dirty contact here trill give "tinny" rccept ion.