Service manual

2. Measure Channel 08 LO Resistance
– Send *RST to multiplexer
– Send CLOS (@nn08) to close chan 08, where nn = card #
– Trigger the DMM with TRIG SGL and note reading
– Send OPEN (@nn08) to open channel 08
– Subtract measured value of R24 from DMM reading
– Enter the result in Table 2-2 for Channel 08 LO
3. Repeat for Channels 09 - 15 LO and Channels 91 - 92 LO
– Repeat steps 1 and 2 for channels 09 - 15 LO and 91 - 92 LO
– Use CLOS (@nncc) and OPEN (@nncc), where nn =
card # and
cc = channel # (omit leading zeroes in nn)
– For Channel 91 LO, subtract combined value of R24 + R30
– For Channel 92 LO, subtract combined value of R24 + R27
Ch 08 - 15 and 91 - 92
GU Measurements
1. Make Hardware Connections
– Turn mainframe power OFF
– Connect DMM leads as shown in Figure 2-8
– Turn mainframe power ON
Figure 2-7. Chs 08-15 and 91-92 LO Measurements Connections
Figure 2-8. Chs 08-15 and 91-92 GU Measurements Connections
28 Verification Tests Chapter 2