Tektronix SCD1000 Service Manual page 172

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SCD1000/SCD5000 Service Manual
External Calibration
Perform the next step quickly to prevent excessive arcing.
11. Carefully but quickly remove the High Voltage probe from pin 2 (some
arcing may occur, but moving quickly will reduce it).
12. Carefully insert the High Voltage probe onto pin 9 on the Write Gun Socket
(FOCUS) as shown in Figure 5-1S.
13. Check the DVM for a reading of -5.86 V ± 0.150 V (SCD1000) or -6.12 V
±0.1S0 V (SCDSOOO).
14. If necessary, adjust R44 (Coarse Focus) for a DVM reading of -S.860 V
± O.OS V (SCD1000) or -6.12 V ± O.OS V (SCD5000). This will center the
coarse focus in its range. This pot is reached via rear panel access hole
using a small flat-blade screwdriver.
1S. Remove the high, voltage probe.
16. Disconnect the high voltage probe ground lead.
17. Turn off the SCD power and wait about 10 seconds for the High Voltage
capacitors to discharge before reinstalling the CRT socket cap, the CRT
High Voltage shield, and the instrument covers.
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