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Handy-PEA is a compact, highly portable continuous-excitation type
chlorophyll fluorescence analyser. The rugged yet lightweight design
makes Handy-PEA particularly suitable for rapid, large scale
screening of samples in the field or greenhouse in both research and
teaching applications.
Handy-PEA
utilises the continuous excitation fluorescence measurement
principle. High time resolution (100KHz initial sampling rate)
electronics and saturating levels of illumination (3000µmol m-2
s-1) permit accurate monitoring of the time dependent
fluorescence induction kinetics observed when a sample is strongly
illuminated after a period in darkness (Kautsky effect). Typical
measurements take only 1 second, providing a very high throughput
capability for large scale screening of samples. Additionally,
Handy-PEA offers a high degree of measurement flexibility for
research applications involving longer duration measurements or
pre-programmed user-defined multi flash protocols.
Dark
adaptation of samples is achieved via lightweight (approx. 6.2
grams) plastic leafclips. The clips are suitable for use on a range
of samples including broad leaved plants, grasses, needles and
macroalgae. The leafclip shutter blade is closed to prevent the
entry of light and the clip left in place for several minutes to
provide dark adaptation. During this period, the white leaf clip
body and stainless steel shutter blade reflect incident sunlight and
reduce heating at the leaf surface.
Data acquisition is synchronously
triggered, initially at a rate of 100 kHz (10µsec intervals) with 12
bit (0-4095 bit) resolution. As the fluorescence induction slows,
lower acquisition rates are automatically applied for the remaining
recording period. Up to 1000 complete measurement files containing
full trace data of any recording duration (0.1 - 300 Secs) may be
stored in memory.
- Weight -
565gms
- Battery -
3 rechargeable (Ni-MH) 3.6V 1.8Ahr.
- Battery
Life - Typically 8 - 9 hours when performing 1 second recordings
at 120 measurements/hr.
- Integral
switch mode battery charger 8-13.5V input (nominal 12V input)
- Display -
8 line x 20 character LCD display.
- Illumination -Focused array of ultra-bright red LED's with NIR
short pass cut-off filters.
Peak wavelength 650 nm. Spectral-line half width 22 nm.
Max. intensity at leaf surface >3000µmol m-2 s-1.
- Detector -
Fast response PIN photodiode with RG9 long pass filter.
- Electronics - 16 bit microprocessor, 12 bit resolution, A/D 10µsec
acquisition rate, 8 bit DAC for light source control, real time
clock.
- Record
Length - 0.1 - 300 seconds
- Memory -
512K battery backed RAM (sufficient for up to 1000 one second
duration recordings with full trace data).
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