  RR Lyrae stars are pulsating stars, many of which also show a long-term
variation called the Blazhko effect which is a modulation of amplitude and
phase of the lightcurve. In this work, we searched for the incidence rate of
the Blazhko effect in the first-overtone pulsating RR Lyrae (RRc) stars of the
Galactic halo. The focus was on the Stripe 82 region in the Galactic halo which
was studied by Sesar et al using the Sloan Digital Sky Survey (SDSS) data. In
their work, 104 RR Lyrae stars were classified as RRc type. We combined their
SDSS light curves with Zwicky Transient Facility (ZTF) data, and use them to
document the Blazhko properties of these RRc stars. Our analysis showed that
among the 104 RRc stars, 8 were rather RRd stars, and were excluded from the
study. Out of remaining 96, 34 were Blazhko type, 62 were non-Blazhko type,
giving the incidence rate of 35.42% for Blazhko RRc stars. The shortest Blazhko
period found was 12.808 +/- 0.001 d for SDSS 747380, while the longest was 3100
+/- 126 d for SDSS 3585856. Combining SDSS and ZTF data sets increased the
probability of detecting the small variations due to the Blazhko effect, and
thus provided a unique opportunity to find longer Blazhko periods. We found
that 85% of RRc stars had the Blazhko period longer than 200 d.
