GE LOGIQ E9 Service Manual page 309

GE
D 5535208-100, R
IRECTION
7-5-8-9 Analog CW (cont'd)
Name: Service Diagnostics / Analog CW / GRX aCW Dither Injection
A signal is injected in the dither input and result in the received I/Q data is checked. The test signal
generator is used for signal injection where the input signal is f0=2.521 MHz, the BP filter at 3.1 MHz
and a mixer frequency of 2.5 MHz. The dither input is enabled for this test, while the Pedof inputs are
disabled. The DITHER_GAIN parameter values are set to 0, 1, 2 and 3. The parameter values
corresponds to Dither gain of 0 dB, -7 dB, -19 dB and -30 dB respectively. The RMS and the RMS
attenuation between the different gain settings in both I- and Q-data are tested.
Are the probes connected? The test will run with probes connected to the scanner, but it is
recommended to disconnect all probes before running diagnostics.
Run Time: 00:05
1.) Verify the following tests pass:
-
-
If these tests pass, and the GRX aCW Dither Injection test fails:
2.) Replace the CW GRX board.
Name: Service Diagnostics / Analog CW / GRX aCW Pedof
In the test, the two center frequencies of 2 MHz and 6 MHz are verified. These frequencies are set by
switching the Pedof band pass filter. The GFI test signal generator is used to input sine waves. The
Pedof test signal input is enabled. The dither and Pedof probe inputs are disabled. Sub tests using
combinations of input signal frequency, Pedof band pass filter settings, mixer clock frequency, test
signal gain, and IQ gains are run.
Parameters tested: fdop, spectrum peak, RMS, SNR and THD on both I- & Q-data. With this test the
Pedof (SD probe) CW path on the GRX board is tested.
The aCW Pedof Test will only be run on the CW64 board.
Are the probes connected? The test will run with probes connected to the scanner, but it is
recommended to disconnect all probes before running diagnostics.
Run Time: 00:05
1.) Verify the following tests pass:
-
-
If these tests pass, and the GRX aCW Pedof test fails:
2.) Replace the CW GRX board.
. 2
EV
GFI Tests
Analog Receive Tests
GFI Tests
Analog Receive Tests
Chapter 7 Diagnostics/Troubleshooting
LOGIQ E9 S M
ERVICE ANUAL
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