The andrzej soltan institute for nuclear studies

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TUKAN 8k
MCS - Multichannel Scaling mode
1.2.3
The device hardware and software provides optional medium speed
Multi-Channel Scaling (MCS). The MCS acquisition mode is used for applications
requiring a measurement of intensity vs. time and includes interface logic to TTL
pulses coming from some measuring instrument. The maximum counting
frequency is 12.5 MHz and is synchronized with the 33 MHz PCI clock. Event
counting can also be performed on signals coming directly from a
detector/amplifier by using the ADC BNC input. The ADC BNC input signal is
then processed by the Single Channel Analyzer (SCA). This mode of operation
allows event counting up to a frequency of 1 MHz. The computer controlled SCA
window makes signal filtering easy.
The Multi-Channel Scaler records the counting rate of events as a function of
time. When a scan is started, the MCS begins by counting input events in the first
time slot (channel 0) in the digital memory. At the end of a preset period of time,
called "dwell time", the MCS advances to the next channel in the memory and
continues the counting. The dwell and advance processes are repeated until the
MCS has scanned through the preset number of channels. A single scan through
all selected channels is called a sweep, which may be repeated selected number
of times. In multi-sweep mode the accumulated data may be either replaced by
the new sweep or they may be summed channel by channel. Starting a sweep,
as well as advancing from one channel to the next, may be triggered internally or
externally. 
Performance
·
Maximum counting rate – 12.5 MHz
·
Dwell Time – up to 2
24
 steps (one step = 1.9 µs)
·
Sweep Length – up to 8192 channels with automatic or externally triggered
sweep repetition 
·
Acquisition modes – summing or replacing
·
No dead time between channels and sweeps
·
Possibility to use Single Channel Analyzer as an counting input (SCA formed
from MCA with threshold presetting)
Presets
·
Sweep length (number of channels)
·
Low and high thresholds
·
Dwell time
·
Sweep count
·
Input signal gating mode
·
Input signal type
·
Triggering mode
·
Advancing mode
·
Accumulation type
·
Stop mode

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21
Tukan-8k Analyzer
Parameters accessible on-line
·
global time
·
current channel number
·
current sweep number
Inputs and outputs
ANALOG INPUT Accepts positive unipolar or bipolar semigaussian type pulses
with shaping time constants >= 100 ns as well as amplified detector pulses
without shaping. DC Coupled. The dynamic range is 10mV to +10 V (Zin = 1
kOhm). Overload protection over +12.5V and below -0.5V.  BNC connector. Also
used as SCA input.
GATE Accepts TTL positive (+2.5V) level. Computer controlled
Gating/Non-gating and Coincidence/Anticoincidence mode. Active state of this
signal (asserted for coincidence and unasserted for anticoincidence) must occur
prior to and extend 200 ns beyond the peak of the analog pulse. LEMO
connector. Also used for EVENT pulse gating in MCS mode – in the latter case it
must cover the entire pulse.
D-CONNECTOR (9-pin) – only for MCS
§ EVENT – TTL input (1 kOhm input impedance, DC coupled, positive polarity);
Input signal to be counted by MCS. Minimum width 40 ns, minimal gap
between two successive pulses 40 ns.
§ TRIGGER – TTL input (1 kOhm input impedance, DC coupled, positive
polarity); Input signal, starts a new sweep, provided External Triggering has
been set. Minimum width 40 ns 
§ ADVANCE - TTL input (1 kOhm input impedance, DC coupled, positive
polarity); Input signalcauses the acquisition to step to the next channel,
provided External Dwell has been selected. Minimum width 40 ns.
§ STOP - TTL input (1 kOhm input impedance, DC coupled, positive polarity);
Input signal causes the acquisition to terminate at the end of the current
sweep. Minimum width 40 ns.
§ ACQUIRE – TTL output (>2.5V); 100 ns wide output pulse generated when the
MCS data acquisition is invoked.
§ NEXT - this positive TTL (>2.5V) output pulse generation depends on selected
advancing method 
o auto-advancing - 100 ns wide output pulse generated when the MCS
advances from one channel to the next.
o external advancing – a positive pulse level asserted when current sweep is
processed and de-asserted after current sweep completion.
§ SCA – TTL output (>2.5V); 100 ns wide output pulse generated when the

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22
TUKAN 8k
ungated SCA detects a pulse inside the voltage window with peak detection
provided.
§ RESERVED – reserved for user added feature.
Tukan-8k-PCI
1.3
Tukan-8k-USB
The TUKAN-8K-USB box can operate in two modes: as multi-channel pulse
height analyzer (MCA) and as multi-channel scaler (MCS). Additionally there is
also possible to operate the device as the Single Channel Analyzer (SCA).
The device is controlled by host computer via USB. After disconnecting USB, the
device continues data acquisition and collects experimental data, which remain
available after reconnecting the device to the host. When operating
autonomously, the device needs to be supplied by external power supplier.
Specifications:
I/O Connections and LED Indicators
Powering the device
MCA - Multichannel Analyzer mode
MCS - Multichannel Scaling mode
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