CHAPTER 5
OPERATION OF THE JUNIOR-PAM
be typed into the right text box. The content of the latter box is stored as
additional instrument identifier on the JUNIOR-PAM. The contents of
both text windows are written in the first line of each record file.
5.6.2
Box (15) - Measuring Parameters
<Meas. Light>
Measuring “pulses” are delivered at 5 Hz (if actinic
light is switched off or the actinic light level is smaller than 4) or at 100
Hz (after manual selection, during saturating pulses or at actinic light
levels higher than 3). Each “pulse” can include 1 to 5 “flashes”. The
numbers of “flashes”/”pulse” is adjusted in the <Freq.> field. The rela-
tive intensity of a single “flash” is set in the <Int.> field. Note that an
increase in flash intensity normally increases the Fo fluorescence level.
An increase in the numbers of flashes/pulse increases the Fo level only
if some PS II reaction become closed by the now higher integrated
measuring light intensity. In this case, the flash intensity needs to be re-
duced.
<System Pars.>
Two signal amplifications are available in the <Gain> field: the higher
gain level (level 2) results in about threefold increased fluorescence val-
ues than the lower one. The <ETR-F.> is used fore calculations of elec-
tron transport rates (see section 6.3). The <ETR-F.> corresponds to the
number of photosynthetically effective quanta absorbed by the sample
relative to the number of photosynthetically effective incident quanta.
<Clock>
The clock utility executes repetitively one out of 6 different functions:
saturating pulse analysis and 5 preprogrammed sequences
(<Act.+Yield>, <Induct. Curve>, <IC +Recov.>, <Light Curve> and
<LC +Recov.>). The interval time can be adjusted between 10 s and 50
min depending on the action triggered and experimental demands.
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