Agilent Technologies e4419b, e4418b manual Worst case error on 15.8V maximum power setting

Measurement Uncertainty Analysis – Instrument Accuracy Test

Measurement Introduction

Worst case error on 15.8V maximum power setting

Error = ((10ppm x 15.8V) + (0.3ppm x 100.0V)) + (0.5ppm x 15.8V) + 5((0.15ppm x 15.8V) + (0.1ppm x 100V))

=257.75uV

Percentage Error = 0.00163%

Voltage Error

Distribution

Standard Uncertainty

257.75uV

Rectangular

148.8uV

The relationship between the applied voltage from the Universal Source to the corresponding power is given from:

1mW = 0.14493mV

This is a linear relationship, for example, 0.1mW is equal to 0.014493volts. This relationship is valid between 0dBm and –30dBm.

However, above 0dBm a look up table is used for voltage to mW conversion. This is due to the sensors non linear behavior at higher power levels. The voltage correction at the appropriate points is shown in Table A-2.

Table A-2: Voltage Correction Multiplier

Power (mW)	Voltage Correction Multiplier
1	1
10	1.006577
100	1.075533

Therefore to attain a power of 100mW as shown in the Table A-2, instead of applying 14.4493 Volts, the actual amount of voltage required from the Universal Source would be:

14.4493 x 1.075533 = 15.6Volts

Agilent E4416A/E4417A Service Guide A-7