Troubleshooting The A1 Interconnect Assembly - Agilent Technologies 11713A Operating And Service Manual

Troubleshooting the A1 Interconnect
Assembly
The A1 interconnect assembly contains the power supply and
connectors for other major assemblies.
To Troubleshoot the A1 Interconnect Assembly
1. Pull out the A2 driver, A3 latch, A4 remote local logic, and A5 GPIB
board assemblies.
2. Turn the power on, and measure the voltage at TP1 on the A1
interconnect assembly. 5 Vdc ± 5% should be present.
3. Measure the voltage at TP2. 24 Vdc.± 5% should be present.
4. If either voltage is not acceptable, disconnect both ribbon cables to
the front and rear panels and remeasure the voltages at TP1 and
TP2.
5. If the voltages at the test points are still unacceptable, replace the Al
interconnect assembly.
Assembly Overview
The power supply is enabled when the LINE ON/OFF switch is set to
the ON position. The power supply provides +5 Vdc for the logic
circuits, and +24 Vdc at 0.650 amperes continuous to drive attenuators,
relays, or switches connected to the driver.
A "crowbar" circuit is incorporated that causes the primary line fuse to
blow if the ac input voltage exceeds the ratings on the power mains fine
module.
In addition, the Al interconnect assembly provides GPIB lines level
shifting to meet the IEEE specifications for a listener device.
Servicing the Attenuator/Switch Driver

Troubleshooting the A1 Interconnect Assembly

11713A Operating and Service Manual 8-13