We present the data and analysis of VLBI observations at 1.6 , 5 and 15 GHz of a sample of faint Gigahertz Peaked Spectrum ( GPS ) sources selected from the Westerbork Northern Sky Survey ( WENSS ) .
The 5 GHz observations involved a global array of 16 stations and yielded data on the total sample of 47 sources .
A subsample of 26 GPS sources with peak frequencies \nu _ { p } > 5 GHz and/or peak flux densities S _ { p } > 125 mJy was observed with the VLBA at 15 GHz .
A second subsample of 29 sources , with \nu _ { p } < 5 GHz , was observed at 1.6 GHz using a 14 station global VLBI array .
In this way , 44 of the 47 sources ( 94 % ) in the sample were observed above and at or below their spectral peak .
Spectral decomposition allowed us to identify 3 , 11 , 7 , and 2 objects as compact symmetric objects , compact doubles , core-jet and complex sources respectively .
However , many of the sources classified as compact double or core-jet sources show only two components making their classification rather tentative .
This may explain why the strong morphological dichotomy of GPS quasars and galaxies found for radio-bright GPS sources , is not as clear in this faint sample .