A Built-Up Wireless Mast 



THE followiiiR artick' tells how any- 

 one possessing ordiaary working 

 tools, can easily, quickly and inex- 

 pensively construct a mast of a distinctly 

 modern t>'pe not usually found at 

 amateur stations. Since it is built of 

 wood, the mast is light anil easy to 

 erect. It can be readily usotl in close 

 quarters, since it requires few guys, and 

 consequently it can be placed quite close 

 to a fence, building or wall. 



The material should all be clean, 

 straight, white 

 pine, since this 

 wood will with- 

 stand severe 

 weather. All 

 the strips are i 

 in. by 2 ins. in 

 cross-section, 

 and may be 

 bought at any 

 lumber yard. 

 The prices 

 range from i 

 to 3 cents per 

 lineal foot. 



T li e mast 

 should be built 

 on a perfectly 

 flat i)la(e, sueli as a large floor or level 

 concrete sidewalk. First, three pieces 

 of the material about I in. long are sawed 

 off and nailed on the floor to form an 

 equilateral triangle measuring 24 ins. on 

 a side, as shown at A Fig. 2. Next cut 

 off 39 pieces, each 24 ins. long, for the 

 cross-pieces B, C, D, shown in Fig. 2. 

 The ends of these pieces are notched to 

 fit in the triangle formed by the pieces 

 A, as shown in Fig. 3. l-"ach cross- 

 member should be fitted, and when three 

 are finished, they should be marked as 

 one set and put aside. In this manner 

 13 sets arc made. 



When these cross-members are all 

 done, start work on the uprights. Each 

 upright should be 47 ft. long and made 

 by joining several strips by means of 

 scarf joints at least 6 ins. long, using 

 No. 14 wire brads 3 ins. long. 



Having completed the uprights, the 

 cross-members may be put in. The 

 first set is l foot from the bottom, ancl 



Note how the mast is 

 built up in sections 



the remainder are 4 ft. apart. The last 

 section, F in Fig. i, will be 2 ft. long in 

 the 50-foot mast. Ne.xt put in the 

 braces from corner to corner, having 

 tiii'm tight and butting against the 

 cross-members. They must be firmly 

 nailed in place, both to cross-members and 

 uprights. The ends are to be chamfered 

 off to fit the corners, as shown in Fig. 4. 

 The main part of the mast is now 

 finished, and the pole may be put on 

 top. This is a piece, preferably of oak, 

 2 ins. by 2 ins. and 18 ins. long. The 

 top is chamfered off to shed water and 

 the bottom made triangular in shape, 

 so as to fit the step on the top of the 

 mast, as shown in Fig. 6. The three 

 pieces, P, P, P, are of the same material 

 as the mast, and are fastened on the 

 bottom side of the top cross-member, 

 set by means of screws, as shown. The 

 six-sided piece F is fastened under the 

 . three pieces P, P, P, and acts as a 

 bottom for the step. The mast is 

 l)raced by three pieces shown at G in 

 Fig. I. These rest on the ends of the 



Concre/e 



Diagram showing the construction of the 

 built-up wireless mast 



S281 



