  We present the results of a 200 ks Chandra observation of part of the Groth
Strip region, using the ACIS-I instrument. We present a relatively simple
method for the detection of point-sources and calculation of limiting
sensitivities, which we argue is at least as sensitive and more self-consistent
than previous methods presented in the literature. 158 distinct X-ray sources
are included in our point-source catalogue in the ACIS-I area. The number
counts show a relative dearth of X-ray sources in this region. For example at a
flux limit of 1E-15 (cgs) around 20 per cent more soft band sources are
detected in the HDF-N and almost 50 per cent more in the ELAIS-N1 field, which
we have analysed by the same method for comparison. We find, however, that
these differences are consistent with Poisson variations at 2 sigma
significance, and therefore there is no evidence for cosmic variance based on
these number counts alone. We determine the average spectra of the objects and
find a marked difference between the soft-band selected sources, which have
Gamma=1.9 typical of unobscured AGN, and the hard-band selected sources, which
have Gamma=1.0. Reassuringly, the sample as a whole has a mean spectrum of
Gamma=1.4\pm 0.1, the same as the X-ray background. Nonetheless, our results
imply that the fraction of sources with significant obscuration is only ~25 per
cent, much less than predicted by standard AGN population synthesis models.
This is confirmed by direct spectral fitting, with only a handful of objects
showing evidence for absorption. After accounting for absorption, all objects
are consistent with mean intrinsic spectrum of Gamma=1.76 \pm 0.08, very
similar to local Seyferts (abridged).
