Model 579 Fast-Filter Amplifier Operating and Service Manual Printed in U.S.A. ORTEC® Part No.
Advanced Measurement Technology, Inc. a/k/a/ ORTEC®, a subsidiary of AMETEK®, Inc. WARRANTY ORTEC* warrants that the items will be delivered free from defects in material or workmanship. ORTEC makes no other warranties, express or implied, and specifically NO WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
iii CONTENTS WARRANTY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ii SAFETY INSTRUCTIONS AND SYMBOLS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iv SAFETY WARNINGS AND CLEANING INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . v 1. DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
iv SAFETY INSTRUCTIONS AND SYMBOLS This manual contains up to three levels of safety instructions that must be observed in order to avoid personal injury and/or damage to equipment or other property. These are: DANGER Indicates a hazard that could result in death or serious bodily harm if the safety instruction is not observed. WARNING Indicates a hazard that could result in bodily harm if the safety instruction is not observed.
v SAFETY WARNINGS AND CLEANING INSTRUCTIONS DANGER Opening the cover of this instrument is likely to expose dangerous voltages. Disconnect the instrument from all voltage sources while it is being opened. WARNING Using this instrument in a manner not specified by the manufacturer may impair the protection provided by the instrument. Cleaning Instructions To clean the instrument exterior: ! Unplug the instrument from the ac power supply.
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1 ORTEC MODEL 579 FAST-FILTER AMPLIFIER 1. DESCRIPTION The ORTEC Model 579 wideband Fast-Filter Amplifier with Gated Baseline Restorer is a state-ofthe-art hybrid-circuit instrument (Fig. 1.1). It is designed to enhance fast-timing measurements by improving the slope-to-noise ratio and providing ultra-high count rate spectroscopy capability. and Table 1). Excellent dc and gain stability (±50 V/°C and ±0.05%/°C respectively) eliminates the need for a dc-level adjustment (Figs. 1.5 and 1.
2 Fig. 1.2. 579 Output Signals for Ji = JD = Out at 1, 2.5, and 5V. Fig. 1.3. Gamma-Gamma Coincidence System Using a Plastic Scintillator and a Large HPGe Coaxial Detector.
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5 2. SPECIFICATIONS 2.1. PERFORMANCE INPUT SIGNAL AMPLITUDE RANGE ±1.0 V ac, ±5.0 V ac with X5 internal Attenuator; ±35 V dc; input impedance 100 ; 50 optional. S S DIFF Front panel 7-position switch selects a differentiation time constant to control the decay time of the pulse. Decay time 2.2 D with i = Out. The D settings include Out, 10, 20, 50, 100, 200, and 500 ns. / J J J RISE TIME <5 ns with Integrate and Differentiate Out, or .2.2 i for other integrate settings and Differentiate Out.
6 Attenuator. Maximum dc voltage ±35 V. Input impedance 100 (to match preamplifiers); 50 optional. S S CLIP Two front panel BNC connectors to provide delay line clipping of the input pulse. Cable impedance must be 50 . Delay line clip is 2X the cable propagation delay. Gain is reduced by factor of 2 when using cable clip. S 2.4. OUTPUTS OUTPUT Front panel BNC connector furnishes the amplified and shaped signal through Zout,
7 4. OPERATING INSTRUCTIONS Two principal functions may be furnished by the ORTEC Model 579 wideband Fast-Filter Amplifier, depending on the details of the system in which it is installed. The 579 may be used to linearly amplify a small amplitude range into one that is better suited to the requirements of a subsequent instrument in the system; the gain can be set at any level from X0.9 to X500 for this purpose.
8 5. MAINTENANCE 5.1. CORRECTIVE MAINTENANCE 5.2. FACTORY SERVICE The ORTEC Model 579 should require no regular maintenance other than replacement of components that have failed due to age. Always ensure that the replacement components are equivalent to the original parts. No internal trimming or adjustment is necessary for the 579. This instrument can be returned to the ORTEC factory for service and repair at a nominal cost.
