Studer SW V4.0 OnAir 1000 Operating And Service Instructions page 198

OnAir 1000 Digital Mixing Console
Correlator Meter Setting:
4-12 Service
5. Check the voltages at the following test points:
TP101/201/301/401: 285 mV
TP102/202/302/402: –370 ±20 mV
TP103/203/303/403: +2.55 ±0.10 V
6. Feed a 400 Hz, –5.5 dB
Check: All LEDs of the bargraph must be illuminated.
Check the voltages at the following test points:
TP103/203/303/403: +3.8 V
7. Feed a 400 Hz, –32 dB
Check: Only the lowest green LED of the bargraph must be illuminated.
8. Check the voltages at the following test points:
TP103/203/303/403: +170 mV
9. If required, proceed with the "Correlator Meter Setting" paragraph below.
10. Once finished, make sure to re-establish the console settings as they were
before the alignment.
1. The correlator meter can be aligned regardless of the VU or PPM meter
setting.
2. Make sure that all parameters are correctly set according to the "Proce-
dure" paragraph above.
3. For the following adjustment, an oscilloscope with a 10:1 probe is re-
quired. Set the Oscilloscope to: x = 0.5 or 1 ms/div.; y = 0.2 V/div., select
AC coupling, and proceed with step no. 4.
If no oscilloscope should be available, setting the trimmer potentiometers
RA204 and RA404 to their center positions is a tolerable makeshift solu-
tion. In such a case, proceed with step no. 8.
4. Feed a 400 Hz, –42 dB
5. Connect the scope probe to pin 6 of IC109.
6. Measured wave form, typical:
Ratio 1:1
Adjust the pulse duration ratio with trimmer potentiometer RA204 to 1:1;
the pulse amplitude becomes then minimal.
The measured wave form is depending on the input signal level.
7. Connect the scope probe to pin 6 of IC309 and perform the same adjust-
ment with RA404.
8. Feed a 400 Hz, –9 dB
9. Align for a reading of +1.35 ±0.20 V
and trimmer potentiometers RA105/305.
Check: Only one LED at the far left of the bargraph scales is illuminated.
10. Feed a 400 Hz, –9 dB
11. Align for a reading of +200 ±5 mV
trimmer potentiometers RA106/306.
Check: Only one LED at the far right of the bargraph scales is illumi-
nated.
12. Repeat steps no. 8 to 11 above until optimum alignment is reached.
13. Once finished, make sure to re-establish the console settings as they were
before the alignment.
SW V4.0
AC
DC
DC
sine-wave signal to the console.
FS
±0.1 V
DC
sine-wave signal to the console.
FS
±30 mV
DC
sine-wave signal to the console.
FS
Min. amplitude
sine-wave signal, L/R out of phase, to the console.
FS
, using the test points TP107/307
DC
sine-wave signal, L/R in phase, to the console.
FS
, using the test points TP107/307 and
DC
Date printed: 24.10.03