Dual Mixer Bias Adjustment

This test is performed only on E4440A, 43A, or 45A analyzers with Option 123.

Option 123 consists of a preselector bypass path. This bypass path places a Dual Mixer in parallel with the RYTHM mixer. The Dual Mixer requires that LO drive levels be adjusted in order to optimize the sensitivity and distortion of the PSA. The LO input for the Dual Mixer comes from the SLODA External LO port. This procedure assumes the SLODA adjustment has been performed.

The Dual Mixer requires four ALC bias voltages to be adjusted. Each bias voltage relates to Band 1, 2, 3, and 4. The bias voltages for each band are printed on the Dual Mixer label. These voltages can be read with a DVM on the test connector on the Front End Driver, A13J12.

This adjustment should be performed after replacing the A21 or A13 assemblies.

This adjustment saves an output file which lists the corrections that were stored in the instrument. The output file is saved at this location:

<drive>:\Program Files (x86)\Agilent TME\PSA\Output\<Model_Serial#>

Required Test Equipment

Test Equipment

Model Number

Digital Multimeter

3458A 

Bias Adjustment Board

E4440-60041

 DC Probe

11002A, 11003A

Connection Setup