- Gain Range continuously variable from 1 to 3000
- Integral non-linearity < ± 0.025% for 2 µs shaping time
- Unipolar output noise < 4.0 µV rms for gain=100 and < 3.5 µV rms for gain=1000 (@ 3µs shaping time)
- Bipolar zero cross-over walk < ± 3ns (@ 50:1 dynamic range, 2 µs shaping time)
- LED indicator for high precision pole-zero cancellation without using oscilloscope
- Active filter networks with wide range of shaping times
- Gated baseline restorer with automatic controls of threshold and restoring rate
- Pile-up rejector and live-time corrector
The N968 is a spectroscopy amplifier implemented in a one unit wide NIM module. It accepts the typical outputs generated from either optical feedback or resistor feedback preamplifiers connected with nuclear particle detectors. The output is quasi gaussian with 0 to +10 V output dynamics.
A front panel switch allows to select between positive and negative input signals. Gain setting can be performed continuously in the 10 ÷ 1500 range, product of Coarse, Fine and Superfine Gain. Two internal jumpers allow to set a x 0.1 attenuation and a further x 2 amplification, thus extending the gain range to 1 ÷ 3000. The shaping time values are 0.5, 1, 2, 3, 6, 10 µs.
The Pole Zero cancellation is performed via a front panel screw-trimmer. The module features also a Bipolar output (to be used for timing purposes), an advanced Gated Baseline Restorer circuit (with manual or automatic threshold setting) and a Pile Up Rejector which allows to reject piled up events.
One unit wide NIM unit
- Gain range
1 ÷ 3000
- Pulse shape
UNIpolar shape: quasi Gaussian, peaking time 2.4 Ts pulse width at 0.1% level equal to 2.9 times the peaking timeBipolar shape: approximate derivative, time to crossover 3 Ts
- Integral non linearity
<± 0.025% from 2 µs shaping time
(Measured from 20% to 90% of Full Scale Range)
- Temperature instability(0 to 50?C)
Gain: < ±50 ppm/°C.
DC level: UNIpolar output: < ±10 µV/°C
BIpolar output: < ±30 µV/°C
- Bipolar crossover walk
< ±3 ns at 2 µs Ts for 50:1 dynamic range
- Overload recovery
Recovers to within 2% of rated output from X300 overload in 2.5 nonoverloaded pulse widths using a gain of 1000 for UNIpolar Output. Same recovery from X1000 overload for BIpolar
- Spectrum broadening
Typical: <16% FWHM for a 60Co 1.33 MeV gamma line at 85% of full scale for an incoming count rate of 10^3 to 10^5 counts/s (Unipolar Output, 2-µs shaping)
- Spectrum shift
Peak position typical shift: <0.024% for a 60Co 1.33 MeV gamma line at 85% of full scale measured from 10^3 to 10^5 counts/s (Unipolar Output, 2-µs shaping)
4 µV/ 6 µV (RMS) for UNIpolar/Bipolar output for 3 µs shaping time and coarse gain = 100
3.5 µV/ 5 µV (RMS) for UNIpolar/Bipolar output for 3 µs shaping time and coarse gain = 1000
Compare with Amplifiers (Spectroscopy).
|WN968XAAAAAA||N968 - Spectroscopy Amplifier|