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978 Dual Timer

ORTEC 978 Dual Timer
  • Two Identical Triggered Pulse Generators in a single wide NIM module
  • Manual or Pulse triggered start
  • NIM and ECL output width from 50 ns to 10 s
  • End marker output
  • Functions as a variable width and rate pulser when both sections are cascaded

The ORTEC 978 Dual Timer is a single width NIM module housing two identical flexible triggered pulse generators.
  • Literature +

  • More Information +

    The 978 produces NIM and ECL pulses with width ranges from 50 ns to 10 s when triggered. Output pulses are provided in both normal and complementary formats. A pulse end-marker output signal is provided which can be used to re-trigger the timer for repeat mode. The trigger START can be provided either via an external signal or manually via a front panel switch. The veto input can act as an inhibit gate for the start input signal. The coarse adjustment of the output width is provided via a 10-position rotary switch, while the fine adjustment can be performed via a rotary knob. The two timers may be cascaded to form a pulser with both variable width and rate. Overall accuracy is 10% of full scale plus a temperature coefficient of 0.1% per °C.
  • Specifications +

    Two normal independent, one complementary NIM level and one ECL. Output width 50 ns to 10 s in 9 decade steps, with a potentiometer and locking dial for fine adjustment.
    Dead Time Shorter than the cycle time. (The timer can be triggered well before the end of the timing cycle).
    Rise/Fall Time <2 ns.
    I/O Delay Delay from Start to leading edge of output, or from Reset to trailing edge, is approximately 13 ns.

    Inputs and Outputs

    Start Inputs
    LEMO 00 connector inputs accept fast negative NIM signals with minimum pulse widths of 5-ns. Zin = 50 Ω. ECL inputs are dual pins with Zin =100 Ω.
    Veto Inputs Accept fast negative NIM logic and disables the Start Inputs when logic is TRUE within ±2 ns of Start leading edge. Zin = 50 Ω. LEMO 00 connector.
    Reset Inputs Accept fast negative NIM logic minimum width of 7 ns (15 ns for recurring operation). This input can be applied at any time producing an End Marker. Zin = 50 Ω. LEMO 00 connector.
    End Marker
    Left LEMO 00 (Zout = 50 Ω) connector outputs provide a 15 ns wide NIM logic level where the leading edge is coincident with the trailing edge of the outputs within ±2 ns. Right LEMO 00 (Zout = 50 Ω) provides complementary NIM logic levels out. ECL outputs are dual pin ECL logic Zout = 100 Ω.
    Inverted Out
    and Out Outputs
    Left LEMO 00 (Zout = 50 Ω) connector outputs provide a fast NIM positive going logic level. Right LEMO 00 (Zout = 50 Ω) connector outputs provide a fast NIM negative going logic level. ECL outputs are dual pin ECL logic Zout = 100 Ω.

    Momentary Start
    Switch creates an End Marker and provides a manual Reset.
    Width Switches Nine decade switches from 50 ns to ∞. The ∞ setting provides bi-stable operation.
    Vernier Width
    Provides fine adjustment for each of the Width Switch settings with overlap. Accuracy is ±10% of full scale (temperature coefficient is 0.1% per °C of setting).

    LED flash for 0.1 s or the output width (whichever is greater). At high rates the flashing rate is not synchronized with the input.

    Electrical and Mechanical
    +6 V, 55 mA; –6 V, 560 mA; +12 V, 17 mA; +24 V, 40 mA; –24 V, 18 mA.
    Weight Net 0.9 kg (2 lb)    Shipping 2.25 kg (5 lb)
    Dimensions NIM-Standard single width 3.43 x 22.13 cm (1.35 x 8.714 in) front panel per DOE/ER-0457T.
  • Ordering Information +

    Model       Description
    978 Dual Timer