For specially prepared `bar diode' tunnel diode junctions that consisted entirely of germanium, it was found that uniaxial compressional stresses applied to the junction caused reversible changes in the peak and valley currents. The changes were linear in stress, and reproducible from diode to diode; for stresses normal to (100) or (111) junctions, increases were observed of the order of 20% at maximum stress (4000 kg cm^-2). For (100) junctions an approximate interpretation of the observations is given; it is based on the detailed changes of valence band structure under uniaxial stress. It was confirmed that the peak currents of conventional alloy dot diodes - where a metallic phase lies close to the junction - sometimes increase by 50% under stresses of about 500 kg cm^-2 applied via the alloy dot, that valley current increases can be even larger, that both effects are non-linear in stress, and that the reproducibility from diode to diode was poor. The results on bar diodes indicate that the non-reproducible high non-linear stress sensitivities of certain alloy dot diodes involve a secondary effect of stress - such as dislocation movements near stress concentrations. The observations were made at room temperature and, since the donor impurity on the n-type side of the junctions was arsenic in all cases, phonon effects were unimportant.