234 Keysight N9010A EXA Service Guide
Front End Control Troubleshooting
A15 Front End Control Description
A15 Front End Control Description
Purpose
The A15 Front End Controller board functionality can be broken down into (3)
main categories
1. Provides switch control logic and bias voltages to the major RF front end
assemblies in the analyzer.
2. Contains on board circuitry providing various signal outputs to other
locations within the analyzer.
3. Provides control logic for various instrument options within the analyzer.
These signals are routed to and from the A15 via ribbon cables, wiring
harnesses and coaxial cables. The RF front end assemblies require the correct
control logic and bias in order to function properly. If the voltages from the A15
are not correct, the RF input signals will most likely be displayed at an incorrect
power level if they even get displayed at all.
Depending upon the age of the analyzer and the options installed, one of four
different A15 Front End Control board assemblies may be installed. These are
most easily distinguished by their HW ID, listed in the Show Hardware screen
(press System, Show, Hardware). But they are more easily referred to by their
"nickname":
The FEC and EFEC-Lite are functionally-equivalent. They both support the
microwave high-band preamplifier options (P07, P13, P26) and the electronic
attenuator option (EA3). The EFEC supports the millimeter-wave preamp
options (P32, P44), IF Out options (CR3, CRP) and provide routing of the IF
signal to support the 40 MHz analysis bandwidth option (B40). The S-EFEC is
identical to the EFEC with the exception that it does not support Opt CRP. The
EFEC is standard on older EXAs with Opt 532 or 544 and the S-EFEC is
standard on newer EXAs with Opt 532 or 544.
The FEC is no longer available for replacement. It is replaced by the EFEC-Lite.
The EFEC is the recommended replacement for the S-EFEC.
HW ID Nickname Description
8 FEC Original Front End Controller
41 or 75 EFEC Enhanced Front End Controller (only HW ID 75 supports Opt 532 and 544)
71 EFEC-Lite Enhanced Front End Controller without IF MUX hardware
170 S-EFEC Streamlined Enhanced Front End Controller - Does not support Opt CRP