Tips and Jottings

Radio Record, Volume III, Issue 24, 27 December 1929, Page 31

Tips and Jottings

Storing Spare Wire. F/XxPERIMENTS involving the con4 struction of special coils often lead to an accumulation of insulated wire of various gauges. An excellent method of storing lengths of wire of this kind is to wind them on a wooden pole, about an inch in diameter and three feet long. Holes are drilled in the rod at intervals of an inch or so for its complete length. The spare lengths of wire are then wound separately on the pole, and the ends passed through the drilled. holes. ‘he rod may .then be conveniently supported on two brackets on the wall and left free to rotate so that the particular length of wire wanted may be easily pulled of. Set-Building Hints. WHEN building a set if a centre- . punch is employed before drilling the necessary holes the accuracy of their positions will be ensured. With very large holes such as those of 3-8in. diameter ‘as used for one-hole fixing components, it sometimes simplifies drilling if a small guidé hole is made first. In order to ensure that the ‘panel and baséboard will fit nicely into the cabinét, it is best to screw the panel and the terminal strip to the baseboard with all three in place in the cabinet. This should be done before the components are mounted on the baseboard but after those. which go on the panel are in place. Simplifying Tinning Operations. if peed) tinning of the ends of the lengths " of wire used in wiring a receiver, especially fine or flexible wires, will be greatly facilitated if the soldering iron is adapted, for the purpose. The tstal trouble encountered in this operation

is that it is difficult to put a good coating of solder on the wire without rubbing it about on the iron. If a fairly deep V-shaped groove is filed in one of the faces of the bit (at right angles to the handle) a considerable amount of solder can be welted into it without any risk of its running off. Using Fixed Condensers. N ALL straight circuits with the reaction coil in series" with an impedance or resistance, it is advisable to provide a by-pass condenser to ensure satisfactory control with a suitably small reaction coil. In certain other circuits, ever though reaction is not used, it is often found that the ixielusion of a small fixed condénser will give improved results, and an example of this fact will be found in most reflex circuits whete the ’phones are connectéd in the anode ¢ircuit of the reflexing. valve. When, on the other hand, no reaction is -uséd, a telephone condenser does not betome a necessity, except in special circuits, It may, however, sometimes bé found to imprové the tone of signals, and for this reason is sometimes provided, though generally in the case of telephone reception the actual improvemént is hard to detect. For Fine Soldering. WHEN fine wires have. to be soldered in a rather inaccessible position, it is often difficult to place the tip of a soldering-iron of ordinary size down into position. A useful method of overcoming this difficulty is to bind a few turns of really stout wire round the head of the iron, leaving a projecting tip. This can be turned, and makes quite a satisfactory ‘iron for soldering fine wires in grooves where the iron itself is too big to enter.