AbstractSince 1971 the magnetic Ap star 52 Her has been investigated with respect to its magnettic field and radial velocity on the observational basis of 140 photographic Zeeman spectrograms obtained at the 2m‐telescope in Tautenburg. Additionally, 47 normal spectrograms were used for the determination of the radial velocity only. The technical foundation for observation and measurement is considered. The main purpose of the paper, however, is the documentation of the observations and the measuring results. Deductions drawn from the material assorted here or taken from other sources are put off to following paper