We report mu SR experiments carried out on a series of heavy-electron pseud
obinary compounds U(Pt1-xPdx)(3) (x less than or equal to 0.05). For x less
than or equal to 0.005 the zero-field muon depolarization is described by
the Kubo-Toyabe function. However the temperature variation of the Kubo-Toy
abe relaxation rate Delta(KT)(T) does not show any sign of the small-moment
antiferromagnetic phase with T-N approximate to 6 K (signalled by neutron
diffraction), in contrast to previous reports. The failure to detect the sm
all ordered moment suggests it has a fluctuating(>10 MHz) nature, which is
consistent with the interpretation of NMR data. For 0.01 less than or equal
to x less than or equal to 0.05 the muon depolarization in the ordered sta
te is described by two terms of equal amplitude: an exponentially damped sp
ontaneous oscillation and a Lorentzian Kubo-Toyabe function. These terms ar
e associated with antiferromagnetic order with substantial moments. The Kni
ght shift measured in a magnetic field of 0.6 T on single crystalline U(Pt-
0.95 Pd-0.05)3 in the paramagnetic state shows two signals for B perpendicu
lar to c, while only one signal is observed for B parallel to c. The observ
ation of two signals for B perpendicular to c while there is only one muon
localization site (0, 0, 0), points to the presence of two spatially distin
ct regions of different magnetic response.