Service manual

July 1, 2002 68P81076C25-C
6-4 Troubleshooting Waveforms: ASTRO Spectra Waveforms
Waveform W6: SPI Bus Programming ADSIC
Waveform W7: Receive Audio
Tek stopped:
T
1
Ch1
T
18 Acquisitions
Tek stopped:
T
2
Ch2
T
11
13
M 50ns Ch1 2.2 V
W6: SPI Bus Programming ADSIC.
Trace 1 - ADSIC_SEL*
Trace 2 - SPI_SCK
Trace 3 - MOSI
Note: These waveforms are typical to
any device on the SPI bus.
Ch1 Freq
= Hz
No period
found
Ch1
Ch3
5.00V
5.00V
5.00V
MAEPF-24381-O
T
T
T
103 Acquisitions
Tek stopped:
T
2
Ch2
1
3
4
M 200us Ch1 2.20 V
W7: Receive audio: Receiving
1KHz tone @ 3KHz deviation, -60dBm. Volume set to rated audio.
Trace 1 - IRQB @ DSP (8KHz)
Trace 2 - SD0 @ C412 on Command Board
Trace 3 - SPKR_LOW Out of U450
Trace 4 - SPKR_HI Out of U450
Ch1 Freq
7.9118kHz
Low signal
amplitude
5.00V
10.00V
500mV
10.00V
Ch1
Ch3
Note 3: Actual level is dependent upon volume setting.
MAEPF-26077-O
Ch4
3
T
T
T