PSI System Controls and Diagnostics
A500 User Manual
A500_UM_090115 Page 53 of 61
Mezzanine fiber-optic card or
application I/O card not
functioning
Incorrect jumper settings on
cell controller card
Ensure jumper settings are
correct.
No response to gate/trigger
inputs of gate option board
A500 is not set up to pass
signals through to fiber optic
outputs
Check configuration.
Set another fiber optic output
to duplicate the required
outgoing trigger, and confirm
that it lights as expected.
Configure as required
Signals unable to drive the
50R inputs to TTL threshold
Test with signal generator
with 50R output
Use appropriate driving circuit
No counts seen by gate-
counter board
Pulses do not exceed threshold
voltage for sufficient time.
Tee off and check levels with
oscilloscope.
Use signal generator to drive
the input.
Use appropriate device to
drive the inputs
Pulse height comparator
feeding gate-counter inputs
incorrectly configured.
Tee off and check levels with
oscilloscope.
Use signal generator to drive
the input.
Ensure pulse height
comparator is correctly set up.
No trigger input present to
start counting.
Test with internal triggering.
Ensure correct trigger signal is
present.
Very low count rate.
Increase integration period.
Use integration period
appropriate to the anticipated
count rate.
Incorrect pulse polarity.
Tee off and check levels with
oscilloscope.
Use NIM standard fast logic
pulses only.