HP 435B Service Manual

Se
rvi ce

M o d e l 435 Β
8- 4
So ld e rin g
Un so ld e rin g
Un so ld e rin g
Aid

Ι fro m co nn ect i o n
R es in (fl ux )
So ld e r
Pr otect iv e
coat in g
R e m o v e e x cess fl ux fr o m
soldered area before
application of protective
coating .
Co mp o n e n t r epl ace m e n t
C ir cui t b oa rd r e p a ir
W i r in g
co rr os i o n pr otect i o n
N e x t, c h ec k t h e a mpli fie r
's o
u
t pu t
v
o
l
tage .
It will
pro b ably a l so b e c l ose to o n e of t h e
s
upply vo l tages
(e .g ., g r o und, +12 V , o r -12 V ) . Ch
ec
k to see t h at t h e
o u t pu t co nf o rm s to t h e inpu ts . For
e
x ampl
e,
if t h
e
inv e rt in g inpu t is m o r e p
os
i
t
iv
e t
h
an t
h
e non-
inverting inpu t, t h e o u t pu t s h ould b e n
egat
iv
e ;
if
t h e non-inverting inpu t is m o r e pos i t iv e t han t h e
inv ert in g inpu t, t h eou t pu t s h o uld b e pos i t iv e . If t h e
o u t pu t co nf o rm s to t h e inpu ts, c h ec k t h ea mpli fie r 's
e x te rna l c ir c ui t ry . If t h e amplifier's ou t pu t does n ot
co nfo rm to its inpu ts, it is proba bly def ect iv e .
Ta b le
8-1
. E tc h e d Circ u it Sol d ering E q u ipment
S p ecificat i on

.----~ -

Item R ecommen d e d
W attage r at in g : 47 1 /2-56 1 /2

Un ga r No . 776ha ndl e wi t h
Tip T e mp : 850-900 deg r ees

* Un ga r No . 4037 H eat in g
Uni t
So ld erin g t ip *

Ι So ld e rin g

Ι *S h a p e : po in te d

Ι * Un ga r No . PL 111
Su ct i o n d e vi ce

So ld a pul t b y Ed s ynCo .
Arl eta, Ca lif o rni a
Mu st n ot di sso lv e etc h e d c ir-

Fr eo n, A ceto n , L ac qu er
c uit b ase b oard material or

Thinner, I sopropyl Alcohol
conductor bonding agent .

(100% ο dry)
R es in (fl i ι x) co r e, hi g h tin
co n te n t (60/40 t in / l ead ),
18 ga u ge (S W G) pr eferr e d
Co n ta min at i o n ,

Ι Goo d el ect ri ca l in s ul at i o n,

Ι Sili co n e R es in s u c h as
cor r os i o n - pr e v e n t i o n pr o p ert i es
Ι
GE DRI-FILM **88 -~
* For working on etched boards ; f or general purpose
work, u
se
Ungar
No . 1237 H eating Unit (37 .5 W , tip temperature of 750-800 degrees)
and
Ungar No . PL113, 1/8-inch c hisel tip
.
**General
Electric
Co
., Silicone
Products
D ept ., W aterford, N ew York, U
.S .A
.
Operational Amplifiers(Cont'd)

Fi g ures 8-2, 8-3, a nd 8-4 s h o w t ypi ca l o p e r at i o n a
l
Wh e n tr oubl es h oot in gan o p e r at i o na l a mpli fie r c ir-

a mpli fie r co nfi g ur at
i
o
n
s .
Fig
ure 8-2 s
h
o
w
s α
ηοη -
c ui t, m easure t h e vo l tages at t h e two inpu ts ; t h e

inv
ert in g buffe
r
a
mplifi
e
r wi
t
h
α ga
in o f
1 .
Figur
e
diff er e n ce b et w ee n t h ese v o l tages s h ould b e less

8-3 is α non-inverting amplifier wi t
h
ga
in d
ete
r -
t han 10 mV . ( N ote : Thi s tr o ubl es h oot ing proce dur e mind ed by R 1 and R 2 . Figur e 8-4 is an inv ert in g
will n ot w ork f o r op e r at i o na l a mpli fie rs whi c ha r e

a mpli fie r wi t h α ga in
d
ete rmin ed by R 1 and R 2 .
co n fig ur e d as co mp ar ato rs .) Α diff er e n ce vo l tage
mu c
h g
r eate r t h a n 10 mV indi cates tr o ubl e
in
t
h
e
a mpli fie
r
o r i ts e x te rna l c ir c ui t ry . U s ua lly, t hi s dif-
f
e
r
e n ce
w
ill
b
e se v e r a
l
v o l ts a nd o n e of t
h
e inpu ts
will b
e
v e ry c l ose
to
o n
eo
f
t
h
e s upply v o
l
tages (e .g .,
+12 V o r -12 V ) .
I NPU
T
I NPU T I MPE DA N C E-VER Y H IG H
OU T PU T I MPE DAN C E-VER Y L O W
F ig u re 8-2 . Non-inverting Amplifier (Gain =1)

HP 435B Specifications

General

Brand	HP
Model	435B
Category	Measuring Instruments
Language	English