With MEASARsolo we offer a complete measuring system to operate single channel electron multiplier. Using the software with the unit, the high voltage for the CEM at constant bias-voltage between CEM and anode, the discriminator level and the dead time of the preamplifier and the duration and number of the measuring intervals can be programed from PC or laptop. The measured data can be saved as .txt files and inserted into an evaluation program with drag&drop. During measurement, the last 16,000 measuring data are available in real time as a bmp graphic.
If a constant source of radiation is present (such as a vacuum measuring tube), then the measurement of the Counts vs. High voltage plots can be used to check in which condition the channel electron multiplier is (position of the optimal working point, see Gain Characteristics) and if the dead time and the threshold of the discriminator are correctly selected. When the radiation source is shut off, the measurement of the dark pulse rate of the CEM preamplifier combination is possible.
The MEASARsolo is available for operation either with negative or positive high voltage (MEASARsolo-N and MEASARsolo-P) or with a switchable high voltage (MEASARsolo-S).
Fig. 5 Typical measuring run with MEASAR. With help of the measurement Counts vs. High voltage the discriminator threshold and the correct dead time of the preamplifier can be set. The system is then correctly preset for the actual measurement. |
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Parameters
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Model |
Units |
Range |
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MEASARsolo-N |
V |
- 128 to - 4095 |
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High Voltage |
MEASARsolo-P |
V |
+ 128 to +4095 |
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MEASARsolo-S |
V |
±128 to ± 4095 |
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HV slope (1 bit) |
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V/s |
±100 or ± 800 |
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Preamplifier threshold |
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mV |
- 3 to - 130.5, step size = 0.5 |
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Preamplifier deadtime |
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ns |
15 - 30 - 60 - 100 |
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Measurement time interval |
|
ms |
unlimited, stop by command, or |
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(1 to 65535) x 10 |
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Measurement repetitions |
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unlimited, stop by command, or |
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1 to 255 automatically repeated |
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CEM overload protection |
MEASARsolo-N&S |
µA
|
max. anode current (1-15) x 1.024 |
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MEASARsolo-P&S |
cps |
(1-15) x 204800 |
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Current measuring |
MEASARsolo-N |
µA |
full scale = 16.38375 |
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Charge accumulation |
MEASARsolo-N |
nC |
up to 335.54 µC |
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Anode bias |
|
V |
±120 (±10) |
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