Agilent Technologies 856290216 service manual External Mixer Bias Adjustment Non-Option

14. External Mixer Bias Adjustment (Non-Option 327)

Assembly Adjusted

Al5 RF assembly

Related Performance Test

There is no related performance test for this adjustment.

Description

A voltmeter is connected to the spectrum analyzer IF INPUT with the external mixer bias set to off. The bias is adjusted for a 0 Vdc output.

SPECTRUM

Al4ANALYZER

DIGITAL VOLTMETER

Al5 RF SK116

Figure 2-23. External Mixer Bias Adjustment Setup

Equipment

DVM . . . . .,..................................................... HP 3456A

Adapters

Type BNC (f) to SMA (m) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1250-1200 Type BNC (f) to dual banana plug . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1251-2816

Cables

BNC,122cm (48in) HP 10503A

Procedure

1.Press luNE) to turn the spectrum analyzer off, and disconnect the ac power cord. Remove the spectrum analyzer cover and connect the equipment as illustrated in Figure 2-23. Fold down the Al5 RF assembly. Reconnect the power cord and set the luNE) switch to on.

2.Set the HP 3456A controls as follows:

Function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DC VOLTS

Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..O.lV

Resolution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..lOOmV

3.On the spectrum analyzer press (AUXCTRL), EXTERNAL MIXER, BIAS, then BIAS OFF.

4.Adjust A15R926 EXT BIAS ZERO for a DVM reading of 0.000 Vdc f12.5 mV.

2-56 Adjustment Procedures