GB967367A - Improvements in or relating to a device for measuring and recording pulse frequency - Google Patents

Abstract

967,367. Pulse recorders. TESLA, NARODNI PODNIK. June 1, 1961 [June 10, 1960], No. 19788/61. Heading G1J. In apparatus for measuring and recording the frequency of pulses, the pulses are supplied to a digital pulse counter P which is so arranged that it produces a mark on a record sheet S on receipt of the K-th pulse, the mark being made with a recording device R moving across the sheet S according to a law x = #(t), where t denotes time and x denotes the distance of the device R from a reference point on the track of the device R, so that the co-ordinate xf of a mark made on the sheet S at the arrival of the K-th pulse is xf =#(K/f) and is indicative of the frequency f. The apparatus may be arranged so that after the lapse of a predetermined period the counter P is reset to zero and switched over in such a manner that it produces a mark at the arrival of the K<1> pulse where K<1> is a predetermined fraction of K selected to enable two ranges of frequencies to be clearly recorded on different scales and after the resetting of the counter to zero, the movement of the device R may be stopped tor a period to avoid a gap between the two scales. In a practical embodiment, Fig. 2, a sleeve 5 is moved alternately to the left and to the right by rotation of a screw 2 having a left-hand and a right-hand thread engaged alternately by a spring urged pin 51 housed in a frame 52 fixed to the sleeve 5. The sleeve 5 carries a holder 6 for a recording device 1 and stops 8, 9 located at points a third and two-thirds of the path across the sheet S co-operate with a pin 7 spring-loaded into contact with steps on the sleeve 5. Initially holder 6 moves with sleeve 5 from right to left with pin 7 on the highest step so that in due course it engages stop 9 and prevents holder 6 moving further with sleeve 5 until their relative movement brings the pin 7 down on to the middle step free from stop 9. Holder 6 moves with sleeve 5 again until pin 7 engages the lower stop 8 where it is held until the relative movement brings the pin 7 over the lowest step free from stop 8. Holder 6 and sleeve 5 move to the left hand end and return to the right together with the pin 51 following the other thread of the screw 2. The holder 6 is stopped first and the sleeve continues until the pin 7 has climbed to the top step and movement is reversed. When the pin 7 touches either stop 8 or 9 electric contacts are made to zeroize the counter and switch a relay cicuit so that the K<1>-th pulse is counted instead of the K-th. In order to change the scale of recording over ranges varying within one power of ten, K = 10 K<1>.