Anchoring the Universal Distance Scale via a Wesenheit Template
  A VI Wesenheit diagram featuring SX Phoenicis, delta Scuti, RR Lyrae, type II
and classical Cepheid variables is calibrated by means of geometric-based
distances inferred from HST, Hipparcos, and VLBA observations (n=30). The
distance to a target population follows from the offset between the observed
Wesenheit magnitudes and the calibrated template. The method is evaluated by
ascertaining the distance moduli for the LMC (mu_0=18.43+-0.03 se) and the
globular clusters omega Cen, M54, M13, M3, and M15. The results agree with
estimates cited in the literature, although a nearer distance to M13 is
favoured (pending confirmation of the data's photometric zero-point) and
observations of variables near the core of M15 suffer from photometric
contamination. The calibrated LMC data is subsequently added to the Wesenheit
template since that galaxy exhibits precise OGLE photometry for innumerable
variables of differing classes, that includes recent observations for delta
Scuti variables indicating the stars follow a steeper VI Wesenheit function
than classical Cepheids pulsating in the fundamental mode. VI photometry for
the calibrators is tabulated to facilitate further research, and includes new
observations acquired via the AAVSO's robotic telescope network (e.g., VY Pyx:
<V>=7.25 and <V>-<I>=0.67). The approach outlined here supersedes the lead
author's prior first-order effort to unify variables of the instability strip
in order to establish reliable distances.
