A Corner for Beginners

Radio Record, Volume II, Issue 10, 21 September 1928, Page 26

A Corner for Beginners

By

Observer

Those unacquainted with their sets and who are often troubled with quite simple problems will find in these columns from week to week notes on the elements on radio.

Eliminators. "THESE are becoming increasingly _ popular with those who can harness their sets to the power mains, but they are not playthings. Remember that 280 volts enter them, and if not properly connected may cause a nasty shock as well as a nasty mess in the set. ‘ A case of what can be done through lack of knowledge recently came _ before a local dealer, when a set, refusing to function, was brought in. It appeared that an eliminator had been connected to the set, and on turning on the power something seemed to go wrong-a spark, a splutter, and no more. On examination it proved that no fewer than ten bi-pass condensers had been burnt out. These are not easy to fit, with the result that someone has to pay. Usually it is the set owner. Like everything else in radio, elim. inators are extremely valuable if left alone when set going by the dealer. Under these conditions, or when in. stalled strictly according to instruetions, they function perfectly. If the set owner does not feel confident to install his own eliminator, he is well advised to get it done for him by his dealer, who will see that he is guarded against such mishaps as these. It is worth noting that the Fire Underwriters require that the eliminator case be earthed. Prices. JN most cases, the prices of rudio equipment are standardised, and when a certain price is asked it should be realised that it is the standard,

certainly not above it. Similarly with service. If it is worth calling a man it is worth calling an expert, and as such‘ he must be pid. An incident in this respect is worth noting: A radio enthusiast, desiring to keep up with the times, went to purchase a screen grid valve, tendering 5s. Nothing would convince him, when the retailer asked the usual price, that he (the dealer) was anything more than a cringing profiteer. He had seen them advertised at ds. [ ! ! | "os Crystal Sets. A LITTLE incident which occurred recently serves to illustrate a misconception regarding crystal sets. A would-be wireless enthusiast purchased a well-known make of set, only to be very disappointed. He could get only the local station.

On being told that is all that could be expected of such a set, he expressed great dissatisfaction. An owner of such a set in England could bring in several] stations, including Paris-why couldn’t he bring in at least IYA, 3YA, and the chief Australian stations. Doubtless this question worries many, but its explanation is simple. The B.B.C, plan through ¢o-opera-tive organisation to place at least two stations in the range of erystal owners:in all but the most remote districts. South of Manchester, there are five stations (broadeast) over 1500 watts. These include two stations at Daventry, both 25,000 watts, and London with 5000 watts. Paris, 200 miles from London, operates with 5000 watts. These could all be heard on a good erysta] receiver,

Compare this with New Zealand’g four well-separated stations-1YA (50 watts), 2YA (5000 watts), 3¥A (500. watts), 4¥YA (250 watts). .The factor, of distance must be allowed for. Amplifiers. ¥4 HEN one or two valves are added to a crystal it is not to be expected that, as far as distance getting is concerned, the set would be equal to a three-valve or even a two-valve set, without a crystal. Primarily, an amplifier is intended to put the local station on the speaker at satisfactory strength. Cases are, however, quite common where even Australia has been brought in-off the *phones only. When the crystal set so amplified: fails to bring in other stations it does not indicate any fault; it is merely the normal state of affairs. Lightning Arresters. AS’ is generally known, the inclusion of these between the aerial and the earth is compulsory. Shortly after this measure was taken a local dealer had a humorous if not an illuminating case of misapprehension. In accordance with the regulations, a customer had purchased an arrester and installed it. A few days later the customer, very distressed, returned to the dealer complaining that his lightning arrester was not "working properly." On being questioned, the youthful purchaser, having described how he installed it, ended: "I am quite positive it won’t work. I have watched it now for a very long time and not one flash of lightning have I seen in it!"