2.10 MHz Precision Frequency Reference Output Accuracy, HP 8590 EM-Series Option 004

2.10 MHz Precision Frequency Reference Output Accuracy,HP 8590 EM-Series Option 004

If the EMC analyzer is not equipped with a Precision Frequency Reference, perform \10 MHz Reference Output Accuracy," instead.

This performance veri￿cation test must be performed with the EMC analyzer set in the spectrum analyzer mode.

This test measures the warmup characteristics of the 10 MHz reference oscillator. The ability of the 10 MHz oscillator to meet its warmup characteristics gives a high level of con￿dence that it will also meet its yearly aging speci￿cation.

A frequency counter is connected to the 10 MHz REF OUTPUT. After the EMC analyzer has been allowed to cool for at least 60 minutes, the EMC analyzer is powered on. A frequency measurement is made ￿ve minutes after power is applied and the frequency is recorded. Another frequency measurement is made 25 minutes later (30 minutes after power is applied) and the frequency is recorded. A ￿nal frequency measurement is made 60 minutes after power is applied. The di￿erence between each of the ￿rst two frequency measurements and the last frequency measurement is calculated and recorded.

The related adjustment for this procedure is \10 MHz Precision Frequency Reference for

Option 004, HP 8590 EM-Series".

Equipment Required

Frequency counter

Frequency standard

Cable, BNC, 122 cm (48 in) (two required)

Procedure

The EMC analyzer must have been allowed to sit with the power o￿ for at least 60 minutes before performing this procedure. This adequately simulates a cold start. A cold start is de￿ned as the EMC analyzer being powered on after being o￿ for at least 60 minutes.

1.Allow the EMC analyzer to sit with the power o￿ for at least 60 minutes before proceeding. Connect the equipment as shown in Figure 2-2.

Performance Veri￿cation Tests 2-5