WIRELESS

Wanganui Chronicle, Volume LXXXI, Issue 18967, 19 March 1924, Page 10

WIRELESS

By

The Grid

• Some Practical Hints Regarding Tools, i There is little doubt that many per- ! sons taking up amateur wireless work ' seriously find some difficulty in making ; their own apparatus. Of course many • amateurs, have little desire for this side l of the game and prefer to buy their I sets complete, but these people lose half i the enjoyment to be obtained. For an1 other reason, also, the home construc- ! tion of apparatus is to be recommended, I and that is the ever present question of j expense. Wireless may be an inexpensive hobby if one cares to make it so; on the other hand it can lend itself to •immense expenditure if the worker Js ■ willing. For those who desire to try ; their hands at home construction a few notes may be helpful. In the first place it may be said that some sort of a work bench is necessary. :If one uses the kitchen table the prej siding deity is apt to make rude re- ' marks anent the spots of shellac and j solder left behind. For all.amateur workers one important rule is never to make a mess inside. It is bad enough io spend your time at wireless instead of in the garden; but to add insult to injury by messing up the house will bring trouble quicker than anything. Having therefore set aside for yourself a small roam or shed, be careful to fit a lock to the door. If you fail to do this you will come home some night to find that your pet chisel has been used to uproot tacks, or that young Willie has taken a fancy to your tenon saw, which he is using to cut a brick in half. A few little lessons of this sort soon convince one that a lock and key pay for themselves. The next question to consider is the very serious one of tools. Many amateurs fondly imagine that a set can be built quite easily with a few nails and a pocket-knife. This impression is quite erroneous, since several different kinds of material have to be worked, all of whi£h require different handling. We will assume, for argument’s sake, that the i

amateur has the usual tools to be found in most households, i.e., hammer, screwdriver, bradawl, rip-saw, rule, brace, wood bits, a chisel or two, and perhaps a small file. The screwdriver will usually be too large for practical purtic al purposes and one with a fairly small blade should be purchased. The shank should be long and thin, the best type being that known as an “electriIcian’s” screwdriver. If money allows, several of varying sizes may be purchased, and they will be found extremely handy. The next item is a saw;-usually the homer style of saw is a rip-saw with fairly coarse teeth. This is almost hopeless for wireless work, and a twelve or fourteen inch tenon saw is most desirable. “The Grid” has, howeyer, frequently used a hacksaw in place of a tenon saw with quite good results. The only trouble is that the cut is usually a trifle untrue. But if one is pressed for ready cash a hacksaw can be used for both wood and metal working with a consequent saving. When buying a hacksaw get one of the adjustable type; these take blades from eight to twelve inches in length, and one is not stuck then if the correct size is not obtainable. Another point is that if a twelve inch blade is in use and snaps anywhere within four inches of one end, it is an easy matter to let down the temper, punch and drill another hole, and so save the cost of a blade. These little economics go a long way to cut down expense. Of course fqr general work the eight or nine inch blade is the most suitable and should always be purchased if possible. A tube blade is sometimes handy for cutting thin stuff. Another very important tool is a metal vise, without which no workshop is complete. When purchasing this article get the biggest and best you can afford; you will never regret it. Cheap vises are an abomination; they soon wear and the jaws get loose and chipped; furthermore a heavy strain will often snap the moving jaw completely off. “The Grid” has done

this to one vise himself and seen several others which have broken in the same way.' Incidentally it may be said that if broken th?y can be welded quite successfully by any local oxyacetone specialist. When mounting a vise care should be taken to see that it is set at the right height from the ground. It should be so placed that when you are standing up to file the elbow of the right arm is a little higher than the top of the jaws. In this position the forearm will be horizontal when you are filing, and good, flat filing will be facilitated. It is remarkable how difficult it is to file a flat surface accurately and the correct placing of the vice is very important for this reason. Another important tool is a pair of pliers, or several pairs if possible. If one pair only is obtained, see that’ they have cutting blades for snipping off odd lengths of wire. Take care also that the blades are fairly sharp; the last pair that “The Grid” bought had blades nearly a sixteenth thick at the supposed edges. If possible several pairs of pliers of different types and sizes should be obtained, including a round-nosed pair and a pair with good long flat noses. Pliers are most useful tools to an electrician and he can never have too many kinds. The next item is drilling .appliances. If a good brace is available this may be used for a large amount of work and will do almost all that one needs. If e one can afford it however, a small hand drill of the geared type is most useful. These take straight shank bits from one sixteenth to three sixteenths and greatly help the accurate drilling of panels and such work. Referring to bits it should be noted that the twist drills (commonly called “Morse” bits) are the most suitable since they can be used for almost any material. The most useful sizes to commence with are a three thirty-seconds, a one eighth, a three sixteenths, and a quarter inch. Others can be added as found necessary. The next important tool is the soldoring iron, which should be the friend Of all amateurs. For good and consistent working well soldered joints are essential in a wireless set, and time spent in learning to use the soldering iron will be well repaid. The wirelessamateur has most need for a small iron, and one about a quarter of a pound in weight, or even less, is quite large enough; For very delicate work a. very small iron, made from a piece of No. O gauge wire or something similar, is suitable. The struggles of an amateur trying to solder a piece of forty gauge wire to a piece of thirty with a two pound iron, are very amusing to the onlooker, but somewhat exasperating to the unfortunate amateur. In connection with soldering the use of resin as a flux is strongly to be recommended. This substance is a good insulator and will not allow leakage in the way that some of the paste fluxes are apt to do. Furthermore it is quite non-corrosive and may be used on the finest wires without hesitation. It may be used in the form of a powder by slightly wetting the joint and dipping it in the powdered resin. If the joint is fairly heavy the resin may be applied by holding the hot iron against the joint and applying the lump of resin to it. There are a large number of tools which can find a place in the amatcur/s workshop which are extremely handy but not absolutely necessary. Several files of varying sizes, shapes, and coarseness may be obtained. A set of taps and dies will be found indispensable after a short time. In buying these get a good set while you are about it, preferably of B.A, thread. The Whitworth thread is too coarse for small work and most bought apparatus will be found to have B.A. threads. A set tapping one eighth, three sixteenths and one quarter is enough for most work. Plug taps are not necessary as most holes go right through the material. Another tool which is almost essential is a square, without which accurate work is difficult. A pair of dividers for marking out is extremely useful, as also is a centre punch for popping points to be drilled. Unless a point is popped before being drilled the twist drill is very liable to run out and thus cause inaccurate work. It is , not to be expected tjiat all the above tools will be purchased at once; the strain on the exchequer would be too great. The best way is to purchase them, as required taking care always to buy the best tool of each class that can reasonably be afforded. Cheap tools are a delusion and a snare. Next week “The Grid” will give a few.notes on the methods of using the various tools above mentioned. Yank-Hunting.

“The Grid” wishes to congratulate Mr C. Ruscoe, who has been successful in receiving several American amateurs. Mr Les Mellars is also fairly confident that he has heard an American broadcasting station, since he heard the operator giving the name of the town in California and then announcing that he would close down for ten minutes. Mr Mellars has also received several faint C.W. stations, some of whom are no doubt Americans, although since the code calls have not yet been checked it is not possible to definitely locate the senders. ’ There are now four local amateurs on the list of Yfink-catchers and “The Grid” hopes to hear of some more very soon. The requisites appear to be a knowledge of Morse, an efficient set, and plenty of patience. 2 CDM.

This call has been allotted to the amateur station which two Australian amateurs, Messrs C. McClurcan and J. Harris, have erected on the s.s. Tahiti, and which they are operating on the I voyage from-Sydney to San Francisco I and back. The call should not be confused, with 2 C.M., which is the call of Mr McClurcan’s station in Sydney. 2 CDM has been erected for the purpose? of carrying out some low power DX amateur tests. Mr Mellars informed “The Grid” that on Sunday night he heard a number of C.W. and telephony test messages being sent to 2 CDM from 2C.M. and he also caught fragments of C.W. answers sent from 2 CDM. If any other amateur should hear 2 CDM “The Grid” will be pleased to have particulars. There are a large number of New Zealand amateurs transmitting to this station and care should be taken that one of these stations is not mistaken for 2 CDM. The proper routine is sometimes departed from in amateur tests and it is often difficult to know which station is sending. 2 CDM,is most likely to be calling CQ, CQ, CQ, de 2 CDM etc., followed by a message. So far as 4 ‘The Grid” is aware he will not work much with individual stations.'

Club Notes. The aerial mast on the roof of the Y.M.C.A. went west during the storm last week. On Saturday afternoon Mr R. Robinson, assisted by willing helpers, erected a new mast thirty-twd feet in height. The aerial is now approximately 66 feet high at each end and results should improve. On Saturday night the usual transmission was carried out and, although radiation was somewhat reduced,, reports from stations in the district seem to show a considerable

improvement in strength of signals. The? receiving set at the club station is now in good working order and members should avail themselves of the up portunity to gain experience in operating a valve set. “The Grid” would like to see one night a week set aside for operation of the receiving set by beginners under the supervision of a senior member. General Notes.

Don’t forget the true-blue, dyed-iti-the-blood amateur’s slogan “learn Morse or bust.” Paste this inside your hat and carry it into effect as soon as you can. You don’t know what you are missing through being unable to translate the code that vou hear.

In London recently a microphone was placed in the clock tower of “Big Ben” and listeners-in were able to hear the striking of the famous bell. The English broadcasters are adopting a policy of taking the microphone to the performer instead of the other /way round. In -“Big Ben’s” case it was of course a cape of Mahomet and the mountain, with the microphone as Mahomet I

2 BL (Sydney) has been very loud lately. His modulation is described as perfect while the class of items is excellent. It is rather a pity that Farmers Ltd., (2F.C.) chose 1100 metres for their wavelength since very few amateurs can be bothered getting special coils for this station alone. Furthermore static is usually much worse on the longer waves while the radiation coefficient is also lower.

A wireless paradise; a place where sixty foot trees grow in convenient spots, where static is non-existent and last, but no least, where condenser fiends are summarily executed by having their aerials chopped down and burnt.