Agilent Technologies 66000A, Service Manual, Page: 49 / 53

Manual Backdating 49
Manual Backdating
This section describes changes that must be made to the manual so that it applies to mainframes with serial numbers lower
than those listed on the title page. Look in the following table for the serial number of your instrument, and make only those
changes listed for your instrument. Note that for some changes, you may be instructed to update the instrument if certain
components are being replaced during repair.
Serial Prefix
3302A
3350A
3445A
3445A
66000A
Serial Number
00101-00835
00836-00945
00946-01255
01256-01560
Changes
1 - 4
1 - 3
1, 2
1
Change 1
Make the following changes in Table 5-2:
Change: MP4 from a single subchassis (p/n 5001-9840)
to
two subchassis parts: MP4 (p/n 66000-00004)
and MP5 (p/n 66000-00006).
Change: Screw (p/n 0515-0380) from qty 18 to qty 20
Delete: Cover block, p/n 5040-1697
Change 2
In Table 5-1 and on the schematic, delete VR4, p/n 1902-
0244. In its place add C4, 0.1uF, 50V p/n 0160-4835.
Change 3
In Table 5-1 and on the schematic, delete U98 (1820-
6045) and U99 (1820-0244). In their place add a single
IC assembly, U15, p/n 1LH4-0001.
Change 4
In Table 5-1 and on the schematic change R182 and R187
to 42.2 ohms p/n 0757-0316. Add R188, 42.2 ohms p/n
0757-0316 in parallel with R182 and R187.