3. Description of the QABrowser
Real-time Display and Waveforms
2012-10/4.3A
65
Barracuda & QABrowser Reference Manual
Shows the actual waveform type. Determine means that a new
analyse of the waveform will be performed for the next exposure.
The result will be displayed on screen. The waveform types
supported are:
- DC/HF
- Single Phase
- 3-Phase 6-Pulse
- 3-Phase 12-Pulse
- AMX-4
- Pulsed
The first four can be automatically determined when Estimate is
chosen. The selected or set waveform is also shown with a symbol
on the Real-Time Display, see Indicators and Symbols .
AMX-4
The difficulties when measuring tube voltage on a GE AMX-4 is a well-known problem.
Due to high kV ripple at a frequency of 2 kHz it is hard for most non-invasive
kVp-meters to follow the kV waveform correctly.
This waveform type has an agreement with measurements made with the Keithley
Triad System 37946C mobile filter pack (50-135 kV), which is the only filter package
recommended by GE. According to GE, the use of the standard Keithley 37617C W-R
filter pack (50-150 kV) is not good enough. The results have further been verified with
measurements with a traceable high voltage divider that has sufficient bandwidth to
accurately follow the kV ripple from the AMX-4.
Therefore it is important to select the AMX-4 waveform
under Settings | Conditions.
More about the AMX-4 correction can be found in the
Application Note 1-AN-52020-1 from RTI Electronics
AB.
Pulsed
This waveform type should be used for pulsed fluoroscopy especially when the pulses
do not have a "good" square waveform shape. The exposure time must be longer than
the selected recording time when using this waveform type. Pulsed waveform type is
89
To Next Page
Loading...
Need help?
General