GE Vivid q N, Service Manual

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GE
D
IRECTION
FQ091019, R
EVISION
2 V
IVID Q
N S
ERVICE
M
ANUAL
Chapter 7 - Diagnostics/Troubleshooting 7-13
7-2-4-2-4 PM Tests
• ACW Test
- ACW IQ Symmetry Test
The ACW (analog CW test) is performed when CW problems are suspected. Checks the
symmetry of I and Q signals. Inputs a test signal shifted from the mixer frequency, then
calculates the RMS of the I and Q vectors and compares them. The RMS vectors should be
lower than the defined limits (shown on the report).
For test procedure instructions, see the ACW IQ Symmetry Test section, page 7-61 .
- ACW Matrix Test
The ACW (Analog CW) Matrix Test checks the path of all 32 RX channels to all VCA outputs
on the TR32B board. A test signal shifted from the mixer frequency is generated and the
receive signal amplitude and frequency is then checked. The frequency should be matched
to the frequency shift of the input signal (shown on the Test report).
For test procedure instructions, see the ACW Matrix Test section, page 7-64 .
- ACW Delay Range Test
The ACW (Analog CW) Delay Range Test checks the path of VCA outputs to the Delay taps
in all three frequency ranges. The expected results are shown on the Test report.
For test procedure instructions, see the ACW Delay Range Test section, page 7-68 .
- ACW Pre-Mixer Gain Test
The ACW (Analog CW) Pre-Mixer Gain Test checks the PM Gain level. A test signal shifted
from the mixer frequency is generated and the test compares the 0db RMS to the levels of the
other Gains. The RMS level is expected to be lower than the selected Gain level (as shown
on the Test report).
For test procedure instructions, see the ACW Pre-Mixer Gain Test section, page 7-72 .
- ACW BPF Test
The ACW (Analog CW) BPF Test is used to check the operation of all the Bend Pass filters.
A test signal is shifted from the mixer frequency and then the test checks the filter response.
Attenuation of the filters in different frequencies should be within pre-defined limits (shown on
the Test report).
For test procedure instructions, see the ACW BPF Test section, page 7-75 .
- ACW HPF Test
The ACW (Analog CW) HPF Test is used to check the operation of the High Pass Filters
(300Hz and 600 Hz). A test signal is shifted from the mixer frequency and then the test checks
the filter response. Attenuation of the filters in different frequencies should be within
pre-defined limits (shown on the Test report).
For test procedure instructions, see the ACW HPF Test section, page 7-80 .