The principles of the applied data reduction have been already described in Paper I.
However, for maps observed in orthogonal directions we applied
the program PLAIT
(Emerson & Gräve 1988), which is quite effective in
reducing scanning effects.
The large scale structures have been added (see Paper I for details) by using the data from the
1420 MHz Stockert continuum survey (Reich 1982; Reich & Reich 1986). This
survey is limited to the declination range above 
and was used therefore to correct the data for Galactic longitudes 
233
. For longitudes 
233 corrections have been
applied by scaling the 408 MHz all-sky survey (Haslam
et al. 1982) with a temperature spectral index of 
.
A deviation in the spectral index of 
results
in a temperature change of the maximum of the background emission of
about 0.4 K.