  We present basic observational data on the 6C** sample. This is a new sample
of radio sources drawn from the 151 MHz 6C survey, which was filtered with
radio criteria chosen to optimize the chances of finding radio galaxies at z >
4. The filtering criteria are a steep-spectral index and a small angular size.
The final sample consists of 68 sources from a region of sky covering 0.421 sr.
We present VLA radio maps, and the results of K-band imaging and optical
spectroscopy.
  Near-infrared counterparts are identified for 66 of the 68 sources, down to a
3-sigma limiting magnitude of K ~ 22 mag in a 3-arcsec aperture. Eight of these
identifications are spatially compact, implying an unresolved nuclear source.
The K-magnitude distribution peaks at a median K=18.7 mag, and is found to be
statistically indistinguishable from that of the similarly selected 6C* sample,
implying that the redshift distribution could extend to z > 4.
  Redshifts determined from spectroscopy are available for 22 (32 per cent) of
the sources, over the range of 0.2 < z < 3.3 . We measure 15 of these, whereas
the other 7 were previously known. Six sources are at z > 2.5. Four sources
show broad emission lines in their spectra and are classified as quasars. Three
of these show also an unresolved K-band identification. Eleven sources fail to
show any distinctive emission and/or absorption features in their spectra. We
suggest that these could be (i) in the so-called `redshift desert' region of
1.2 < z < 1.8, or (ii) at a greater redshift, but feature weak emission line
spectra.
