Boxcar Averager Module (4121B)

This module is an ideal component for building boxcar averager systems. It includes a wide bandwidth variable gain AC/DC coupled input amplifier with continuous input offset adjustment and a high speed sampling gate with variable width and delay controls. It operates in normal or two baseline sampling modes and features a switch-selected choice of how many samples are included in the averaging process. Separate outputs for the average and last sample taken are also provided. A gate monitor supplies a synchronized gate output pulse for application to an oscilloscope trigger or for referencing associated processing electronics. Trigger input is ECL or TTL or can be derived from the module’s own adjustable trigger generator.

The module is packaged in a 2-unit wide NIM format and as such requires a suitable NIM rack and power supply to operate. The simplest single-channel system can therefore be produced with one model 4121B module and a suitable NIM rack and power supply (such as the model 4006 or 4001A/4002D. The addition of a second model 4121B and a model 4161A Display/ADC and control module provides a dual channel system with the added capability of allowing the transfer of output data to a computer for external analysis. Further modules can be added to increase the overall number of channels.

The unit can also be used with the model 9650A to build swept-gate waveform recovery boxcar systems, all controlled from the Acquire data acquisition software or via a LabVIEW program using the free driver that can be downloaded from this site.