  We use the numerical renormalization group method to study the O(3)-symmetric
version of the impurity Anderson model of Coleman and Schofield. This model is
of general interest because it displays both Fermi liquid and non-Fermi liquid
behaviour, and in the large $U$ limit can be related to the compactified two
channel Kondo model of Coleman, Ioffe and Tsvelik. We calculate the
thermodynamics for a parameter range which covers the full range of behaviour
of the model. We find a non-Fermi liquid fixed point in the isotropic case
which is unstable with respect to channel anisotropy.
