  We test infinite-dimensional extension of algebra su(k,k) proposed by Fradkin
and Linetsky as the candidate for conformal higher spin algebra. Adjoint and
twisted-adjoint representations of su(k,k) on the space of this algebra are
carefully explored. For k=2 corresponding unfolded system is analyzed and it is
shown to encode Fradkin-Tseytlin equations for the set of all integer spins
1,2,... with infinite multiplicity.
