HP 435B - Page 33

Pe
rf
o
rm a n ce T ests

M ode l 435 Β
4-5 .

P
O
WER REFEREN C E LEVEL T E ST (Cont' d )
211'eMMI 14' .
in
Ι
T HERM
ISTO R
ΜΟ_ UN T
F
PERF ORM ANC E
T
E STS
ΝΟΤΕ
T he P owe
r M ete r m ay be r et urn e d to t h en ea r est H ew l ett- P ac ka rd
off i ce to have
t h e powe r r efe r ence osc ill ato r chec k e d a nd /o
r
ad j u ste d .
R
efe
r to Sect i o n II, P ACKAG ING .
P O WER ME TER

', VCO MP I
r -- -~

INPUT
~ VRF iί
F ig
u re 4-1 . P ower R eference L evel Test Set up
EQ UIPMENT :

Po w e r M ete r . . . . . . . . . . . . . . . . . . . HP 432A
Th e rmi sto r M o un t . . . . . . . . . . . . . . HP 478A-H75
Di g i ta l V o l t m ete r (DVM) . . . . . . . HP 3455A
PR OC EDURE :

1 . Set up t h e DVM to m eas ure
r
es
i
sta
n ce . Co nn ect t h e DVM b etwee n t h e V
RF
co nn ecto r on t h e r ea r pa
n
e
l
o
f
t
h
e
432 Α a nd pin 1 o f t h e t h e rmi sto r m o un t e nd o f
t h e 432 Α in te r co nn ect ca bl e .
2 .

R o und o ff t h e DVM indi cat
i
o
n to two d ec im a l pl aces a nd r eco rd t hi s va lu e as
t h
e
in tern a l brid ge r esista
n
ce (R)
of t h e 432 Α (a ppr o xim ate ly 200 o hms) .
3 .

Co nn ect 432 Α to t h e P owe r
M
ete
r as s h o wn in Fi g ure 4-1 .
4 .

Set t h ePo w e r M ete r LINE sw i tc
h
to ON
(in) and t h e P O W ER REF sw i tc h to O FF .
T he n , w a i t t hir t y minu tes f o r t
h
e
432 Α t h e rmi sto r m o un t to sta biliz e b e f o re
pr ocee din g to t h e n ex t ste p .
5 . Set t h e 432 Α RAN G E sw
i
tc
h to
CO
AR S E ZER O a nd ad j u st t h e fr o n t- p an e l
CO AR S E ZER O co n tr o
l
to
o b
ta
in α z e ro m ete r indi catio n .
6 .

Fine
z
e
r
o t
h
e 432
Α
on t
h e m ost se n si t iv er an ge, t h e n set t h e 432 Α R AN G E s wi tc
h
to 1
m W .
C h ec k t h at D V
M
in
pu t l ea d s a r e i so l ate d f ro m c h ass i s g r o und
w h e npe r fo rmin g t
h e n ext step .
7 .

Set up t h e DVM to
m eas ur e m ic r ov o l ts a nd co nn ect t h e p os i t iv e a nd n egat iv e
inpu t l ea d s,
r
es p ect
iv
e
ly , to t h e V
c οΜ
Ρ
a
nd V RF co nn ecto r s on t h er ea r pan e l of t h e
432 Α .
DIGITA L
V O L T ME TER