In this paper we use some results on weighing matrices W (2 n ,9) constructed using two circulants to obtain infinite classes of orthogonal designs. We also present a method that is used to construct two directed sequences of length n and specific type. We apply this method to W (2 n , 9) and we obtain many new pairs of directed sequences of length n and type $(9 \cdot 2^m,9 \cdot 2^m), \ m=0,1,2,3.$ Using these directed sequences we can obtain many new infinite classes of weighing matrices W (2 n , k ), and orthogonal designs OD (2 n ; a,b) constructed from two circulants.
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