HP 3455A - Page 228

I COMR SlO€“
16 34se>g-«$9o
A
CKT SIDE 8
A14
0345S-66514
Rev.
A
The
value of R44 has been changed from 40 MO to 2 MO to prevent the
zero-detect
compara-
tor from oscillating. Instruments with
Serial
No’s
1622A01056
and greater have this change
incorporated.
**6
Serial numbers 1 622A05231
and above the following
component changes have
been made
to
improve reliability
of A1
0U1
5:
Old Pert
No,
R1:
06B3-4335 (5.1 K1
R18: 0757-0435
(3-92 K1
R19: 0757-0421
(8261
R20: 0757-0442
(10 KJ
CR2: 1901-0040
CR6;
1901-0040