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142IH Preamplifier

ORTEC 142IH Preamplifier
  • Charge-sensitive for universal applications
  • Economical and general purpose
  • Accepts 0 to ±3 kV bias
  • Low noise and fast rise time
  • Built-in protection network
  • Small size
  • Operates in vacuum

The ORTEC Model 142IH Charge-Sensitive Preamplifier is an economical and general-purpose instrument that can be used for universal applications such as x-ray, low and high-energy gamma-ray spectroscopy, and also for alpha and other charged-particle spectroscopy.
  • Literature +

  • More Information +

    The Model 142IH may be used with semiconductor radiation detectors, proportional counters, ionization chambers, and low-gain photomultiplier tubes.

    It will accommodate any detector capacitance up to 2000 pF. Thus the unit is ideally suited for high-resolution spectroscopy applications.

    The preamplifier includes a built-in protection network to prevent damage to the input FET from inadvertently applied overvoltages. Its small size also allows it to operate in experimental vacuum enclosures when required.
  • Specifications +

    Increases with increasing input capacitance. Typical slope, 0 to 100 pF = 27 eV/pF; 100 pF to 1000 pF = 34 eV/pF. Typical performance values, based on silicon equivalent of ε = 3.6 ev at τ = 2 µs, are 1.9 keV at 0 pF; these become 4.6 keV at 100 pF and 35 keV at 1000 pF.
    Rise Time Based on a +0.5 V signal through either output into a 93-Ω circuit and measured from 10% to 90% of peak amplitude; <20 ns at 0 pF and <50 ns at 100 pF.
    Sensitivity Nominal, measured through either output, 15 mV/MeV Si.
    Energy Range 0 to 100 MeV Si.
    E2CRP Maximum energy-squared count-rate product: 8 X 107 MeV2/s.
    Dynamic Input Capacitance 10,000 pF.
    Integral Nonlinearity ≤±0.05% for 0 to ±7 V open circuit or ±3.5 V terminated in 93 Ω.
    Temperature Instability ≤±100 ppm/°C, 0 to 50°C.
    Detector Bias Isolation ±3000 V.
    Open Loop Gain ≥40,000.

    Accepts input signal from a detector and extends operating bias to the detector.
    Bias Accepts the bias voltage for the detector from a bias supply.
    Test Accepts input voltage pulses from a pulse generator for instrument and system check and calibration; Rin = 93 Ω.

    E and T
    (for Energy
    and Timing)
    2 connectors furnish identical signals through 2 output paths; either or both of these outputs can be used as required, and they are interchangeable. Ro = 93 Ω through each connector, and the output polarity is opposite from the input pulse polarity (output pulse polarity is the same as bias polarity).

    Input and Bias
    Test, E, and T BNC.
    Power Cable 3-m (10-ft) captive power cable, ORTEC 121-C1; longer lengths available on special order.

    Electrical and Mechanical
    Power Required
    +24 V, 30 mA; –24 V, 10 mA; +12 V, 15 mA; –12 V, 15 mA. Furnished from NIM bin and power supply through any ORTEC main amplifier or from an ORTEC Model 4002P Portable Power Supply; built-in captive cable is compatible with either source.
    Weight Net  0.45 kg (1 lb).   Shipping  1.3 kg (3 lb).
    Dimensions 3.8 X 6.1 X 13.3 cm (1.5 X 2.4 X 5.25 in.) plus 3-m (10-ft) cable.
  • Ordering Information +

    Model Description
    142IH Preamplifier

    Suggested Cable Accessories
    C-24-12 RG-62A/U 93-Ohm Cable with two BNC male plugs; 12-ft length
    C-36-2 RG-59A/U 75-Ohm Cable with two SHV female plugs; 2-ft length
    RG-59A/U 75-Ohm Cable with two SHV female plugs; 12-ft length