Chapter 5 — Troubleshooting 5-4 General Faults
ML248xx, ML249xA MM PN: 13000-00164 Rev. K 5-3
3. Replace the control PCB.
Fault: No GPIB Communication
Description:
No GPIB communication occurs when connected to a compatible GPIB controller.
Recommended Action
1. Reset the unit to factory defaults and try again.
2. Replace the control PCB.
Fault: Incorrect Operation of BNC Inputs or Outputs
Description:
One or more of the rear panel BNC connectors fail to operate correctly.
Recommended Action
1. Visually inspect all of the BNC connectors. If any physical damage is observed, replace the control
PCB.
2. If there is no physical damage, yet the BNC Inputs or Outputs do not work correctly, replace the
control PCB.
5-4 General Faults
The following procedures refer to general system faults.
Fault: Power Meter Loses Non-volatile Memory.
Description:
The power meter loses all non-volatile memory (stored setups, cal factors, cal factor tables, etc.) when
powered off for more than two minutes.
Recommended Action
1. Confirm the jumper is fitted to J806 on pins 1 and 2. These are the two pins nearest the outer edge
of the control PCB (the STORE ON position, as silk-screened on the PCB).
2. Measure the DC voltage of the lithium battery mounted to the center of the control PCB. This can
be measured across pin 1 of J806 and the ground stud on the rear panel. This battery should
measure 3.2 V. If the voltage is less than 2.8 V, replace the battery or the control PCB.
Fault: Alarm Buzzer Does Not Sound
Description:
The noise generator does not make any sound or the sound is too low.
Recommended Action
1. Reset the unit to the factory defaults and try again.
2. Replace the control PCB.
To Next Page
Loading...
Need help?
General
