Agilent Technologies 11713A, Руководство по эксплуатации и обслуживанию

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11713A Operating and Service Manual 8-21
Servicing the Attenuator/Switch Driver
Troubleshooting the A7 Switch Board Assembly
Troubleshooting the A7 Switch Board
Assembly
The A7 switch board assembly (front panel) consists of 10
non-retriggerable monostable multivibrators.
To Troubleshoot the A7 Switch Board Assembly
1. Check both manual and remote operation.
a. To check the driver in manual operation, turn the driver off and
then on. All attenuator lights and the local light should be on.
b. To check the driver in remote operation, use an appropriate
controller program to execute the following commands:
2. If a function cannot be performed both manually and remotely, there
may be an open line between the attenuator switch on the A7 switch
assembly through the A1 interconnect/power supply and to the A3
latch assembly. To help pin point the problem, use the block diagram
on page 8-11 to further trace the circuitry.
Assembly Overview
The resistor connected to the +5 volts keeps the input to the
multivibrators at a logic high. The voltage across the input capacitor is
0 volts when the front panel pushbutton switches are open.
When a button is pressed, the input voltage on the one shot
instantaneously drops to 0 volts and starts the output pulse. The output
pulse width is controlled by a resistor and capacitor, for example R7
and C5. Nominal pulse width is 17 ms. The pulses are sent to the
local/remote multiplexers on the A4 assembly and become the clock
inputs for the flip-flops on the A3 latch assembly.
LEDs behind the front panel switches indicate the present output state
of the driver as seen by the flip-flops on the A3 latch assembly. The
driver is in the A state when LEDs are on and in the B state when they
are off.
Command Desired Outcome
OUTPUT 728;”Al2345678”
All attenuator lights go on except the local light.
OUTPUT 728;”Bl2345678”
All attenuator lights go off except the remote light.