The Constant Fraction Discriminators CFD8c, CFD7x, CFD4c, CFD1c and CFD1x (11.0.1701.1)
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Thus, it is not required to care for proper combination of
CFD Fraction
(respective potentiometer is disabled) and
CFD delay
as
described for the standard CFD circuits. Nevertheless, a cable must interconnect the
Delay
sockets on the front panel. Using
the right cable length here is mandatory for proper operation of the
bCFD
circuits. The delay must be slightly smaller than the
time delay
dt
0
, between the peak maximum and the zero-crossing of the signal trace (see
). If the cable is too
short, signals with very low pulse heights will not be registered. Please contact
RoentDek
for advice unless you have
received a properly matched system with
bFAMP
for a certain delay-line read-out anode.
Timing signals off the MCP contacts or from a TOF anode may also be operated with a
bFAMP1
and
bCFD
circuit although
operation with standard
CFD(x)
for unipolar input signals is recommended
.
Note, that
CFDx
channels as of
CFD1x
and
CFD7x
(ch1) are not specified for operation with bipolar input signals, however,
they still may give useful timing and pulse height outputs, assuming proper CFD settings’ adaptation to the leading edge’s
shape.
RoentDek
CFD
units hosting
bCFD
boards are recognized by pasted-over
CFD fraction
potentiometers on the respective
channels.
*
A
CFD7x
unit can be modified to host one (standard)
CFDx
circuit plus up to six
bCFD
circuits.
