Dc Continuity Test The Lfe Board And Test Ports (Available With Lfe Option 205/220/420/425); Receiver Noise Figure Test - Keysight Technologies N5247B Service Manual

Tests and Adjustments
Performance Tests
DC Continuity Test the LFE Board and Test Ports (Available with LFE
Option 205/220/420/425)
The DC continuity test verifies that the LFE board is installed correctly and
does not have any opens or shorts in the DC path.
1. Using a DVM, connect one test probe to the center conductor of the RF
port 1 on the front panel.
2. Connect the other test probe to the port 1 bias input (BIAS 1 IN) on the
rear panel.
3. Verify the DVM measures
4. Repeat these steps for each of the other test ports.
If the DVM value is 0Ω or
there is an open or short somewhere in the LFE board/cable path:
—

Receiver Noise Figure Test

Function of the Test: To measure the noise figure of the PNA-X noise receiver
system.
Specification Tested: Test Port Input: Option 029 – Receiver Noise Figure
Equipment Used:
— 346C noise source
— BNC cable
Description of the Test:
1. The analyzer is Preset.
2. The 346C noise source is connected to Port 2. A BNC cable is connected
between the noise source and the +28V VDC output on the rear panel of
the analyzer.
3. The analyzer is set to make a noise power density measurement with an
800 kHz noise IF bandwidth using hundreds of points across the full
frequency range of the noise receiver.
4. The ENR data file for the noise source is read into the analyzer.
1. Your model PNA may not have available all of the LFE Options listed.
Keysight N5247B Service Guide
1
<
>
10Ω, then something is incorrectly installed or
Verify the gray DC bias cables installed in
Cables, All Options, Serial Number Prefixes <6021" on page
"Top Assemblies and Cables, All Options, Serial Number Prefixes
≥6021" on page 6-24
Chapter 6 in the "Bottom Assemblies" section—for your LFE
option—are connected correctly and not open or shorted.
10Ω.
"Top Assemblies and
and the blue RF flexible cables installed in
6-18,
3-45