928 EASY-NIM Multi-Function MCA/Counter/Timer/Rate Meter

Hardware Summary
The range of hardware functions incorporated within the EASY-NIM 928 family members are:
• Multichannel Analyzer
• 200 MHz Pulse Counter
• Timer with internal or external time base capability
• Rate Meter with adjustable alarm threshold
• 6 configurable general purpose inputs
• 2 configurable outputs (rear panel)

Software Summary
Individual “front panel emulators” provide display and user control of the MCA and Counter/Timer/Rate Meter sections. Through the design architecture of ORTEC Connections, the EASY-NIM 928 suite of hardware can be controlled from these applications installed locally or remotely across a network. The optional Programmer’s Toolkit allows custom, user-written programs and control.

EASY-NIM Models at a Glance
The 928 model is a combination of a quad counter/dual timer and multichannel analyzer function. The 928-MCB model is a MCA only instrument while the 928-COUNT2 and 928-COUNT4 models are counter/timer only instruments. Each model, except the 928-MCB, is equipped with two programmable outputs and 6 inputs for internal connection or for connection to external devices which may be assigned to a variety of sources.

All-in-One	Stand Alone
928 Combination MCB/Quad Counter/ Dual Timer module	928-MCB MCB only	928-COUNT2 2 Counters/1 Timer only	928-COUNT4 4 Counters/2 Timers only

MultiChannel Buffer (928 and 928-MCB Models)

ADC	Successive-approximation type with sliding scale linearization
Maximum Resolution	16,384 channels, software selectable as 16,384, 8,192, 4,096, 2,048, 1,024, and 512.
Dead Time Per Event	2 µs including memory transfer.
Integral Nonlinearity	<+0.025% over the top 99% of the dynamic range.
Differential Nonlinearity	<±1% over the top 99% of the dynamic range.
Gain Instability	<+50 ppm/°C.
Dead Time Correction	Software selectable for extended Live-Time correction according to the Gedcke-Hale method or ZDT Live-Time corrections which monitors the counting rate and adjusts the dead-time for fluctuating counting rates.
Data Memory	512 kb.

Inputs and Outputs

ADC INPUT	Accepts positive unipolar, positive gated integrator, or positive leading bipolar analog pulses in the dynamic range from 0 to +10 V; +12 V maximum; semi-Gaussian-shaped time constants from 0.25 to 30 µs, gated-integrator-shaped time constants from 3 to 30 µs, or delay-line-shaped with widths >0.25 µs. Zin = 1 kΩ dc-coupled. No internal delay, BNC connector.
ADC GATE	Optional TTL input. Computer selectable Coincidence mode, Anti-coincidence mode, or Off. Signal must occur prior to and extend 0.5-µs beyond the peak of the pulse; BNC connector. Zin = 1 kΩ.
Optional TTL Input	Computer selectable Coincidence mode, Anti-coincidence mode, or Off. Signal must occur prior to and extend 0.5-µs beyond the peak of the pulse; BNC connector. Zin = 1 kΩ.
PUR	Pile-up rejection input; accepts TTL signal; signal must occur prior to peak detect. Zin = 1 kΩ. BNC connector.
Busy	Busy input used by live-time correction circuits. Accepts TTL signal; signal must occur prior to peak detect. Zin = 1 kΩ. BNC connector.

Presets
Presets may be set which will automatically stop MCB acquisitions. In addition, the Counters and Timers may be configured to start and stop in synchronization with the MCB.

Real Time/Live Time	Multiples of 20-ms.
Region of Interest	Peak count/Integral count.
Data Overflow	Terminates data collection when any channel exceeds 231–1.
Peak Uncertainty	Stops acquisition when the statistical or counting uncertainty of a user-selected net peak reaches the specified value.
Nuclide MDA	Stops data collection when the value of the Minimum Detectable Activity (MDA) for a user-specified MDA reaches the specified value.

Counter/Timer/Rate Meter (928, 928-COUNT2, 928-COUNT4)

Maximum Counting Rate	200 MHz.
Number of Counters	4 (2 in 928-COUNT2).
Number of Timers	2 (1 in 928-COUNT2).
Count Capacity	32-bits.
Pulse Pair Resolution	7 ns.

Inputs and Outputs

Counter Input 1, 2, 3, 4	Fast analog signal input accepts analog or digital pulses up to ±5 V in amplitude on a front-panel BNC connector. Pulses are counted as they cross the discriminator threshold. Computer selection of triggering on either positive or negative slope. Threshold is computer adjustable from –1.6 V to +3 V in steps of 1.5 mV (minimum pulse 30 mV). Computer selection of either 50-Ω or 1000-Ω input impedance, dc-coupled. Minimum input pulse width is 3.5 ns at the discriminator threshold. Maximum counting rate is 200 MHz.
Input 1, 2, 3, 4, 5, 6	Front panel BNC inputs which accept TTL input signals. Each input is considered low when <0.8 V and high when >2 V. Input impedance is 1000 Ω to ground. Each input may be configured as described earlier in the Counter and Timer Setup.
Output 1, 2	Rear panel BNC outputs which act as general purpose TTL outputs. Low is indicated by <0.4 V. High is indicated by >+2.4 V. The outputs can drive 50 Ω. The outputs may be configured under software control as described previously.

Counter/Timer Software Controls

Readout Control

Timer and Counter live values may be polled at any time from the computer. In addition, each Counter or Timer has a 128 word Fifo (First in first out) buffer which holds the previous final Counter result at the moment the Counter or Timer was reset. Using the Fifo, Counters can be configured to be reset once a Timer reaches a preset value. The current Counter value is stored in its Fifo so that the computer can read successive values without the fear of losing results because of sluggish computer operation.

Electrical and Mechanical (All)

USB-2.0	Standard USB connection via a supplied 10-ft. cable.
Indicators	ADC:  Indicates activity for ADC-1. Counter:  Illuminated if any of the four Counters is actively counting.
MCB Software Controls	(Operates with included MAESTRO — see data sheet for details.) ADC LLD:  Computer controlled from 0 to 100% full scale. ADC ULD:  Computer controlled from 0 to 100% full scale. Live Time: Correction  Gedcke-Hale, ZDT. Gate:  Coincidence, Anti-Coincidence, Off.
Power Required	+6 V, 350 mA; –6 V, 225 mA; +12 V, 100 mA; –12 V, 100 mA.
Weight	Net  0.9 kg (2 lb).  Shipping  2.25 kg (5 lb).
Dimensions	NIM-standard, single-wide 3.43 x 22.13 cm (1.35 x 8.714 in.) front panel per DOE/ER0457T.