Table 3-4 Selecting a Test Set When Multiple Units are Configured

Test Set IF Switching

A test set is selected via the built-in capability of the analyzer to generate an addressed

 

command to each test set. Each time you change the {HP-IB ADDRESS} {TEST SET}

 

function (refer to LOCAL [MENU] in the HP 8510C Operation and Service Manual), the

 

network analyzer does the following:

 

• switches the IF signal of the previously addressed test set to external

 

• switches the IF signal of the newly addressed test set to internal

 

• sets the test set’s front panel ACTIVE LED to indicate test-set status

 

• applies the active test set’s IF signals directly to J11 TEST SET INTERCONNECT

 

• passes the inactive test set’s IF signals at J10 through to J11 and on to the next

 

test set or to the network analyzer

 

 

Test Set Addressing

You can change the test set address via program control, or via the network analyzer front

 

panel keys. You must also change the mechanical switches on the test-set’s rear panel.

 

Here’s how:

 

1. Change the test set address via the network analyzer keys;

 

a. On the analyzer’s front panel, press the INSTRUMENT STATE [LOCAL] key, then

 

press {TEST SET}. The test set’s address appears on the display.

 

b. Using the key pad, enter the desired address for the test set, then press [x1]. The new

 

HP-IB address appears on the display.

 

2. Change the test set address via the HP-IB command:

 

From the controller, enter the HP-IB ADDRESS; command, followed by the

 

address value. Refer to the command reference for programming details.

 

3. Reset the mechanical switches on the test-set’s rear panel. Set the switches to match the

 

new HP-IB address displayed on the network analyzer screen.

 

 

RF Switch Driver Control

When the {HP-IB ADDRESS} {TEST SET} function is changed, the network analyzer

 

generates a code sequence. The code sequence is automatically issued across the

 

HP 8510C system bus to the device at the ADDRESS of RF SWITCH .

 

In the recommended configuration, the device is an HP 11713A attenuator/switch driver. The

 

switch/driver in turn controls one or more coaxial switches. These switches, (shown in a

 

Figure 3-3,and Figure 3-4)are used to choose which test set receives the RF output from the

 

network analyzer source.

 

The exact command issued depends upon the new value of the {HP-IB ADDRESS}

 

{TEST SET} value, also shown in shown in a Figure 3-3and Figure 3-4.

 

 

HP 8517B S-Parameter Test Set Manual 3-6

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Image 44
HP 8517B manual Selecting a Test Set When Multiple Units are Configured