Keysight U8903B, Service Manual

Page: 81 / 165

Performance Verification for Digital Generator and Digital Analyzer 4
Keysight U8903B Service Guide 81
Unbalanced output sampling rate accuracy verification
This test measures the sampling rate accuracy on the unbalanced digital audio output of
the U8903B using the Keysight 53132A/53220A frequency counter to ensure that it is
within the published specification.
1 Connect Keysight 53132A/53220A frequency counter input channel 1 to the U8903B
unbalanced digital output channel using the SPDIF or 75
Ω impedance cable.
Figure 4-9 Keysight 53132A/53220A to U8903B unbalanced digital output for unbalanced output
sampling rate accuracy verification
2 Configure the Keysight 53132A/53220A frequency counter as follows:
– Preset the equipment
– Channel 1 input impedance: 50 Ω
– Frequency measurement start arming source: Immediate
– Frequency measurement stop arming source: Timer
– Frequency arming and measurement gate time: 0.5 s
3 Configure the U8903B digital output channel to be tested as follows:
– Preset the U8903B
– Digital output type: Unbalanced
– Digital output voltage: 2.5 V
– Digital output sampling rate: 48 kHz
– Digital output AES audio resolution: 24 bits
– Digital output function: SINE waveform
– SINE waveform frequency: 1 kHz
– SINE waveform amplitude: 1 FFS
– Digital output state: ON
Table 4-10 Unbalanced output sampling rate accuracy specification
Unbalanced output sampling rate accuracy
specification
Equipment used
± 5 ppm Frequency counter
SPDIF or 75
Ω
impedance cable
53132A/53220A
frequency counter
U8903B
unbalanced
digital output