in the system depicted schematically in fig1 a pressure pickup 3 is guided radially to follow the spiral groove of a record carrier foil 2 as the foil rotates , the pickup travelling along a radius which is fixed with respect to a member defining a stabilization surface 1 . a point of friction 4 disposed at the same distance from the record axis as the pickup 3 and caused by soiling ( shown to an enlarged scale ) causes a separation of charges , as described above . the charge produced at the stationary point of friction 4 can flow off to ground along a metallic region 10 on the stabilization surface 1 . the opposite polarity charge remaining on foil 2 is transported together with foil 2 and thus comes to be below pickup 3 . the stabilization surface 1 is also provided with an electrically conductive region 11 beneath the path of pickup 3 , this region being electrically conductively connected to ground . its distance from the foil is less , however , than that between the foil and the mass of the pressure transducer device so that an eventual discharge is effectively prevented from taking place through the pickup system which constitutes the playback means . the stabilization surface 1 of the playback device shown in fig2 is provided with four curved members 5 , 5 &# 39 ;, 5 &# 34 ; and 5 &# 39 ;&# 34 ;, corresponding in physical form to a previous proposal . according to the present invention , these curved members have electrically conductive surfaces connected to a suitable ground . during operation of the system , the foil 2 rotates at 1500 rpm above the stabilization surface 1 . above the curved portions which can be considered to be flow - producing cylinders so to speak , a very thin cushion of air of no more than 2 / 10 mm thickness is formed in the region of the radial crest lines 6 , 6 &# 39 ;, 6 &# 34 ; and 6 &# 39 ;&# 34 ;. the distance between foil 2 and one crest line of one curved portion is of the order of magnitude of 10 - 20μ near the circumference of the foil . the curved portions , when considered in the direction of movement of the foil 2 , as indicated by arrow 12 , are provided with shearing edges 7 , 7 &# 39 ;, 7 &# 34 ; and 7 &# 39 ;&# 34 ; behind the crest lines for the streams of air forming the minimal cushions , the shearing edges being substantially tangential to the direction of movement of the foil 2 above the crest lines . in the region of the shearing edges , which are substantially parallel to the crest lines , the above - mentioned points of friction may form . however , these points of friction are no longer able to adversely influence the quiet movement of the foil and the quality of the signal reproduction since , due to the electrically conductive curved members , the resulting electrostatic charges are concentrated thereat and can no longer cause interference . the electrical conductivity can be provided by a metallic coating which is applied by electroplating , printing or vapor - deposition . the embodiment shown in fig2 has been found to be particularly favorable with respect to deposits of impurities . referring to fig3 a recording or playback signal transducer 3 is guided , with its stylus 3 &# 39 ; in contact with the foil surface , transversely to the recorded tracks on the circular foil 2 , i . e . normal to the plane of the drawing , the tracks being in the form of a continuous spiral , for example , and the foil being rotated about its axis by an axially disposed support plate , not shown . the stabilization surface 1 is provided with curved members , the member 5 being shown , which form support surfaces 5a for the foil 2 . the surface 5a shown in fig3 has a crest line 6 and is provided with a shearing edge 7 which is parallel thereto and is at least 2 mm behind the peak line . during operation , the foil 2 rotates at a high speed , e . g . 1500 rpm , the foil having a diameter , for example , of 20 to 30 cm , above the stabilization surface 1 . this is known to produce a flow of the medium , e . g . air , disposed between the two objects . compared to prior art arrangements , a strong flow component is forced in this instrument tangentially to the direction of movement of the foil by the curved surface 5 protruding from the stabilization surface 1 . in the region of the crest line 6 of the support surface 5a the flow lines are compressed . this produces , analogously to the influence of a cylinder in the path of flow , a subatmospheric pressure above the curved surface which pulls the foil close to the curved portion . above the crest line there forms a stable cushion of air of no more than 2 / 10 mm thickness and the thickness of the air cushion becomes minimal a few millimeters in front of and behind , along the direction of foil rotation , the line of radial movement of stylus 3 &# 39 ; so that the distance between foil 2 and curved surface 5 at those points is of the order of magnitude of about 10μ . the edge 7 provides a defined break - off of the tangential flow component sufficiently behind the line of movement of the stylus 3 &# 39 ; so that the break - off turbulence remains without influence on the playback quality . if the system is operating perfectly , foil 2 does not physically contact surface 5a . the stable cushion of air may be disturbed , however , by small particles or deformations protruding either from foil 2 or from surface 5a , effecting physical contact of the two parts . as a consequence , the separation of electrostatic charges may result . it has been found in experiments that if the curved member 5 does not have a shearing edge 7 , the point of tangential flow transition travels between the air cushion above the curved portion 5 and the air cushion above the remaining stabilization surface 1 . this produced undesirable height fluctuations in the region of the line of movement of the stylus 3 &# 39 ;. since a very short distance is required below the line of the element for recording or playing back , it does not matter that outside the region of curvature 5 the foil moves away from the stabilization surface 1 by an amount of up to several millimeters . on the contrary , with such a great distance the influence of dirt deposits is reduced . with heavy soiling , dirt will also be deposited on the curved portion 5 . however , experiments with a foil of 210 mm diameter indicated that this occurs only at the shearing edges . the stabilization surface of an apparatus for recording or playing back signals which is provided with curved members as described above improves the quiet movement of the foil under the recording or playback stylus , and thus the playback quality . in addition , the strong guiding effect of the curved surfaces as a result of the formation of a strong flow component tangential to the direction of movement produces a minimum cushion in the region of the line of movement of the stylus which is substantially independent of the setting of the height of the support plate . the deposits of dirt at defined points which are harmless to the playback permits easy cleaning of the stabilization surface and thus the directed elimination of a source of interference . the stabilization surface provided with the above - described curved members can be produced either as an injection molded piece , or ridges with the appropriate profile may subsequently be applied to the possibly curved stabilization surface . the system according to the invention can be employed to advantage in any of the presently known recording or playback systems which involve use of flexible foil record discs and pressure playback transducers . it will be understood that the above description of the present invention is susceptible to various modifications , changes and adaptations , and the same are intended to be comprehended within the meaning and range of equivalents of the appended claims .