Service manual

3. Check Channels Leakage
• Send CLOS(@nn00) to the FET Multiplexer to close channel
00, where nn is card number (typically 01)
• Send TRIG SGL to DMM
• Record the DMM reading in Table 2-1
Positive Polarity, HI to LO, Channels
• Send OPEN (@nn00) to the FET Multiplexer
4. Check Tree Leakage
• Send SCAN:PORT ABUS to the FET Multiplexer to enable the
Tree Switches
• Send CLOS(@nn00) to the FET Multiplexer to close channel
00 and Tree Switch A, where nn is the card number (typically
01)
• Send TRIG SGL to DMM
• Record the DMM reading in Table 2-1
Positive Polarity, HI to LO, Tree A
• Send OPEN (@nn00) to the FET Multiplexer
• Send CLOS(@nn15) to the FET Multiplexer to close channel
15 and Tree Switch B
• Send TRIG SGL to DMM
• Record the DMM reading in Table 2-1
Positive Polarity, HI to LO, Tree B
• Send *RST to the FET Multiplexer
5. Change Polarity
• Turn power supply and mainframe power OFF
• Connect DMM, power supply, and resistor as shown in
Figure 2-7
• Turn power supply and mainframe power ON
• Set power supply output to +10 Vdc ± 0.1 Vdc
6. Repeat Steps 2 through 4
• Record all results in Table 2-1 as
Negative Polarity, HI to LO
Verification Tests 2-13