ORTEC digiBASE-E, Руководство пользователя

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Fine gain is software-controlled within MAESTRO; see Section 3.1.3.
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APPENDIX A. SETTING THE COARSE GAIN
JUMPER
The digiBASE has 3 coarse gain settings, 1×, 3×, and 9×, determined by setting a jumper within
the unit. the factory setting is 1×.
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To change the coarse gain:
Disconnect the digiBASE from PoE cable and wait 1 minute for the internal circuits to
completely discharge.
With a 5/16-in. wrench, remove the nut from the A INPUT and B OUTPUT connectors.
With a 0.050-in. Allen wrench, remove the 4 set screws that hold the shroud in place.
Slide the shroud off of the socket to expose the internal circuit boards.
Locate the 3-pin jumper on the rectangular board that does not have the smallest of the three
boards. It is labeled ANALOG BOARD and p/n 921007.
Orient the digiBASE so the tube socket faces away from you. In this orientation, when the
jumper bridges the left-most and center pins, the coarse gain is 1. When the jumper bridges
the right-most and center pins, the coarse gain is 3. The gain is 9 when the jumper is removed
(turned at 90
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to the connector and placed on only one pin to avoid losing it). These settings
are illustrated in Fig. 19.
After putting the jumper in the desired location, slide the shroud back over the unit, carefully
guiding the USB and ENABLE INPUT connectors through the holes in the panel.
Replace the set screws.
DANGER
HIGH VOLTAGES are present on the tube socket and inside the unit. Never
operate the digiBASE with the shroud removed or without a detector installed on
the socket.
CAUTION
Do not touch any components on the circular board. Oils from your fingers
can contaminate the components and result in poor operation of the bias
supply.