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1-Channel MCP Detector MCPD25 Manual
1-Channel MCP Detector MCPD25 Manual | Surface Concept GmbH
• Check the detector output by means of any electronics and software or with an oscilloscope where the
input is terminated with 50Ohm.
• The dark count rate without any source should be as given in the specification sheet.
• Now you may start carefully with an electron source observing the detector output.
If sparking occurs, turn down the high voltage immediately and wait some time (up to 5
min.). Start the “Start-Up” procedure again with an increased ramp time. Turn off the high
voltage completely, stop the procedure and call your provider for further assistance, if is
it not possible to reach the operation voltage without sparking.
The detector operation voltage “
MCP-B
” is given in the specification sheet. It is always
given in reference to the MCP front voltage “
MCP-F
”. The maximum reference voltage for
“
MCP-F
” is also given in the specification sheet.
Note
Example for voltage ramping:
Assume the following operation voltage for “MCP-B” in respect to “MCP-F”:
+1,800V and a reference potential for “MCP-F” of +1,000V. A ramp time of a few minutes should be used to
increase “MCP-B” to +1,800V. Then a ramp time of approx. 3 min. should be used to increase the external
reference voltage from 0V to +1,000V in parallel with the “MCP-B” voltage from +1,800V to +1,900V.
Figure 3: Schematic sketch on voltage ramping with external reference voltage.
