HP 8924E, Сборка

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Chapter 14, Diagnostics Descriptions
Description of the Digital Assembly Diagnostics (CDMADIAG)
N:\mkt\MANUALS\HP8924C\ALR\diagnos.fb
IQ Demodulator Q
Out Sense This point measures the Q Out of the IQ Demodulator IC. LOIF_Q_DEMOD_S
Q Offset Reset This point verifies that the demodulation has corrected for
the 1/2 period clock in the reverse Q Channel. Q_LEAD_I
LO/IF/Demodula-
tor Temperature
Sense This point measures the ambient air temperature of the
LO/IF/Demodulator assembly. LOIF_TEMP_SENSE
Table 134 I/Q Modulator
Measurement Explanation and Suggestions Measurement Point
RF Input
Detection The RF input to the I/Q Modulator assembly is moni-
tored using a detector. (The RF signal comes from the
Signal Generator Synthesizer.) IQMOD_IN_DET
I/Q Modula-
tion Output
Detection The RF output of the I/Q Modulator assembly (to the
Output Assembly) is monitored using a detector. IQMOD_OUT_DET
Baseband I
Detection This point monitors the combined level of the I Noise
and I Data baseband signals. (The signal is then buff-
ered and fed to the I/Q modulator IC.) IQMOD_I_MOD_DET
Baseband Q
Detection This point monitors the combined level of the QNoise
and QData baseband signals. (The signal is then buff-
ered and fed to the I/Q modulator IC.) IQMOD_Q_MOD_DET
I Gain Control This point monitors the level of the I baseband modu-
lation signal immediately after buffering by an adjust-
able amp. IQMOD_I_GAIN
Baseband I and
Q Offset The I and Q modulation signal offsets are measured IQMOD_I_OFFSET
IQMOD_Q_OFFSET
Quadrature
Adjust Voltage
Error This point measures the summed output of the DI and
DQ signals from the IQ Modulator IC. IQMOD_VERR
I/Q Modulator
I Control Volt-
age This is the I quadrature adjust signal that is derived
from the quadrature Adjust Error Voltage. IQMOD_VCI
Table 133 LO/IF/Demodulator (Continued)
Measurement Explanation and Suggestions Measurement Point