Agilent Technologies e4419b, e4418b manual + Input, Thermistor Mount, Vcomp

Adjustments

Power Reference Oscillator Level Adjustment

Note	The power meter may be returned to the nearest Agilent Technologies
	office to have the power reference oscillator checked and/or adjusted.

Power Meter Power

ref

Agilent 432A

Power Meter Digital

Voltmeter

VRF	+ INPUT
Vcomp	INPUT

Thermistor

Mount

Figure 3-3: Adjustment Setup

For this adjustment the following mathematical assumptions are made:

Equation 1:

2Vcomp(V1 – V0) + V02 – V12

P = ----------------------------------------------------------------------------------

meas 4R(CalibrationFactor)

can be manipulated to give the following:

Equation 2:

V1 = Vcomp + V0 – Vcomp2 – (10)–3(4R)(CalibrationFactor)

by using the following assumptions:

V02 – V12 = –(V1– V0)2

The error in doing this is:

–(V12 + V02 – 2V1V0) – (V02 – V12) = – 2V02 + 2V1V0 = 2V0(V1 – V0)

So if 2V0(V1 – V0) « 2Vcomp( V1 – V0) , that is, V0 « Vcomp then the error can be ignored. In practice Vcomp ~ 4Volts and V0 < 400∝V . The error is less than 0.01%.

Agilent E4418B/E4419B Service Guide 3-7