Agilent Technologies 2948, 2712A manual Iwarning

Service Model 8904A

IWARNING I

Proper grounding of the instrument.Any interruption of theprotective (grounding) conductor (inside or outside the instrument) or disconnection of the protective earth terminal will create a potential shock hazard that could result in personal injury. Grounding one conductor of a two conductor outlet is not sufficient. Whenever it is likely that the protection has been impaired, the instrument must be made inoperative (that is, secured against unintended operation).

I f this instrument is to be energized via an autotransformer, make sure that the autotransformer’s common terminal is connected to the earth terminal of the power source.

High voltages inside the instrument. Areas with line voltages inside the instrument include the rear panel, power supply, and the line switch cable harness. AC voltages as high as 300 V pp can be present on the backlighting drive to the LED display. (The drive circuitry is on the front right corner of the A2 Digital Assembly.)

Working around charged capacitors. Capacitors inside the instrument can still be charged even if the instrument is disconnected from its source of supply.

Replacing line fuses.Make sure that only 250 volt fuses with the required rated current and of the specified type (normal blow, time d e b , etc.) are used for replacement. Do not use repaired fuses or short-circuited fuseholders. To do so could create a shock or fire hazard.

Disposing of the memory backup battery. The memory backup battery on the A2 Digital Assembly is a lithium battery. (A2 is the large, horizontal circuit board under the top cover near thefront of the instrument. The battery itself is near the front right corner of the board.) The following procedure is recommended for its disposal:

Discharge the battery by soldering a 50 kR resistor across both battery terminals. Complete discharge will occur after one year, at 25°C.

Under Resource Conservation Recovery Act (RCRA) regulations, the com- pletely discharged battery is considered “nonhazardous. However, the user must be responsible for individual state and country regulations for battery disposal.

Do not unplug any boards in the Multifunction Synthesizer unless the instrument isunplugged or switched to S T B Y (standby). Some boards contain devices which can be damaged if the board is removed when the power is on. Use conductive foam when removing MOS devices from sockets. Use care when unplugging ICs from high-grip sockets.

8-2 rev.15DEC89