Specifications

Two couplers on these two paths provide samples of the Forward or Re

verse signals that feed the Reference input of the Down Conversion Mod

ule.

The stimulus signal is then output to the DUT via the Port 1 and Port 2

Modules mounted directly to the Port 1 and Port 2 front panel connectors.

Both Port Modules have integrated bias tees that accept user supplied DC

bias signals for Port 1 and Port 2 from the rear panel input connectors.

The bias signals are injected onto the center conductors of the Port 1 and

Port 2 connectors along with the stimulus signal on either Port 1 and

Port 2, as appropriate for Forward/Reverse operation.This feature can be

used for test devices that require bias on their connector center conduc

tors. The MS462XX allows the bias signals and the RF stimulus signals to

be independently turned off while in Hold operating mode.

The Port 1 stimulus signal can be attenuated in 10 dB steps via the

0 to 70 dB Step Attenuator that is part of the Port 1 source signal path.

The stimulus signal cannot be attenuated when routed out of Port 2.

The reflected and transmitted DUT signals via the directional couplers in

the Port 1 and Port 2 Modules, along with a sample of the output RF

stimulus (reference) signal, are sent to the Down Conversion Module.

Receiver Module

Configurations,

MS462XC

The front end consists of the following items:

Auto-Reversing Module

Switch Module

Port 1 Step Attenuator

Source 1 Switched Doubler Module (6 GHz units) or

Source 1 Switched Tripler Assembly (9 GHz units)

Port 3 Step Attenuator (Option 3C and 3D only)

Port 3 Module (Option 3C and 3D only)

The 10 MHz to 3 GHz signal from the Source Module is routed to the

Auto-Reversing Module. For operation above 3 GHz, the signal is doubled

in 6 GHz models or tripled in 9 GHz models prior to sending it to the

Auto-Reversing Module.

In the Auto-Reversing Module, a coupler provides a signal path for the

built-in level detector that provides a DC signal for the ALC circuits lo

cated in the Source Module. Then, the source signal is switched between

two paths and routed to the respective front panel Port 1 and Port 2 con

nectors. The switching is controlled by the Central Processor Module.

The port 1 stimulus signal can be attenuated in 10 dB steps via the

0 to 70 dB Step Attenuator that is a part of the Port 1 source signal path.

Reference signals, al and a2, are multiplexed to the Reference signal in

put of the Down Conversion Module.

Test signals, bl and b2, are sent directly to the Test signal inputs of the

Down Conversion Module.

2-18 MS462XX MM

FRONT END RF COMPONENTS THEORY OF OPERATION