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Connect α
p
ower meter, spectrum analyzer, RE
d
etector,
AC voltmeter, or oscilloscope = accu rate in the. vicinity of
1 MHz , to the ίπτιιυ mεητ RE OUT connector.
N
ote the
o utpu t level reading Set ΙΓι e Lever 11 ndicalot switch es to
000,999 MHz, and
a
djust the M 115 Gain control such that
t h e output level exactly matches t h e level noted at 001 .000
MHz .
5,3 .12
FINAL FR F ι7ι-I Γ IJ CYClf Ε CK - Μ 301
Connect
f
requ ency co un ter to
t
he Instru nh en t RE O UT
co nnecto r , and set t h e front-panel controls as sp ecifie d in
Section 5.3-4 . Note the frequency
r
ea ding on the co u nter .
If it
d
oes not ag ree ωί th
t
h e selected frequency with in
accuracy specifications, very carefully adjust the M30-1
Fr equency Adjust trimmer (see
F
ig ure 5-5)
u
ntil t h e
desired freque ncy is obtained .
5.4
T ROUBLE SHOOTI N G
Effective
troubleshooting
requires
α
t
hor ough under-
standing of the
b
lock diagrams and circuit description
located in Sectio n 3 of this ma nual; t h en the Performance
Tests in Section 4 and Calibration Procedures in Section 5
will ai d in localizing th e tro ub le symptom to α μαιιίευtαι
mod ule or
P
C boa r d. Once t his
h
as been accomplished,
t he
m
odu le or board can
b
e replace d, or repairp.d with
aid of the pr oper sc hematic and parts layout
d
iagram . In
general, it
is
p
referable to replace α defective modu le or
PC
b
oard assembly .
Equipment troubles are
f
re quently due. simply to improper
control settings ; therefore, before engagi ng in α trouble-
shooting
p
roce du re, be
s
ure front-panel controls are set in
proper operating
p
osition,
R
efer to the operatin g instruc-
tions i n Section 2 of t h is ma nual for α complete expla-
nation of each control's fun ctio n along with typical
o perati ng instructions .
After ve rifyi ng t h at th e t r ouble is not improper setting of
t
he controls o r test setup, make α
t
h oroug h visual inspec-
tion of the instrument for such ο b νίπυτ
d
efects as loose or
m
issing screws,
b
ro ken wires,
d
efective module pin sockets,
loose RE ca bles, and
b
urne d or broken ευ m ριίηεηιs.
After localizing the pr oble m , voltage and resistance chec ks
will
h
el p 1οεαtε the (Ιρ (ρc1 ίν p . rοιπςωηeηΙ ,
Fo r
t
r oub lesh ooting
p
ur poses, it is permissible to operate
the inst rument with any of the plug-in modules or RE
cables removed ;
h
oweve r, t h e instrume n t shoul d be turned
off when removing or installing
m
odu les- If substit u te
m
od ules
a
r
e availa ble, possibly from anot h er M odel 3001
or 3002, this pr ovides an easy metho d of ve rifyi ng if α
s
uspected mo du le ί 5 defective.
5-6
RF ca bles can be discon necte d from the module output
rπηηeςιπ(s, and α power meter or spectrum analyzer
connected
d
irectly
to th e module connector for
p
ower
level or frequency measurements. Fabrication of α
s
h ort
rοαχ adapter cable, terminated in α
m
ating co nnector fur
ι tιe modules on one en d and α BN C connector on the ot h er,
will facilitate connection of test equ i pm ent. (T he SMC
to BN C a dapter cable i n Module Service Kit Κ004 is
designed for t his purp ose .)
T
he Γrηπι-panel ACCU RACY lamps together with the four
internal
m
odu le "unlock indicato r" la mps ai d in t r ouble-
sh ooting ph ase-loc k ed loop problems . One module in eac h
loop rontains an in dicator la mp w hic h lights to ind icate
w h en th at loop is unloc ked. T he lamp s in dicate only which
loops are unloc ke d,
n
ot w hic h mo du le is at fa u lt .
Α problem in the . Ρπωε r Supply may εαιιτe
m
an y symptoms
pointing to other areas and shou l d be c hecked
w
hen t h e
sy m ptom does not clearly i ndicate α sρeelfle
p
roble m ,
L
oss
of
the
-18 V s υιιιιΙσ ,
'υ,
"χπυ ,μίρ, will cause 014,
ACCUR ACY Ιαιιιμ to
f
lash ; while loss of the +118 V supply
will extinguish all lamps. The +1 Β, 18, and +7 .3 V su pp lies
εο rπρ r se th e ΠΡ S2 Α Power Supply whic h forms the rear
ΙιιππιΙ ~, ι ιΙι r. ίι ,".Ιιι-ιιίιειι L ΡιτιΙ" τιιιιαηςε Ο( these 5υρρΙιι? τ is
ίπ d ί cπτ r~ ;1 ι rι the Cα lι dra2'επ Ρrοc~ d ιυε .
5.4 1
TR OUBLE SH OOTI NG HINTS
Following Γ 5 α list σ ( several typical symptoms, accom-
panied fly t h e possible cause(s) o r α troubleshooting μιΟ-
rε dιιι e . It is assu me d
t
he instrument
h
as been prop erly
cali brate d
p
reviously, an d
t
hat α warmup perio d will
ςιι eεαιΙν truu bleshouting .
INTERMITTENT O PER ATIO N - Defective module-pin
sockets ο" loose RE cables .
L
OIN RF O UTPUT (+10 dBm RAN GE) - If
p
ower is
10
d
β ίπω on this
r
a nge, b u t is correct on
t
he 0 dBm ra nge,
micro- τωη" ,c h S1
m
ounted on t h e Step Attenuator is de-
fective, is not being actuate d by t h e Attenuator sh aft, or
α
s
witc h wire ιτ disconnected .
LOW OR NO
R
F- O U T PU T (ANY
R
AN GE) - Defective
Αττεπυατο r or RF ca bles co nn ecti ng to input or output of
Α tιeιιυαιω ,
d
efective
M
eter
B
oar d,
d
efective mod ule
ΜΙΟω -4 Β or M9W .
C hec k t he voltage on
p
in 15 of mo d ule Μ 10W-6!8 .
W
it h
t
he
O U T PUT VERN I ER
f
ully cloc kwise, t he voltage shou l d be
approximately as follows : -2 .5 VDC an the +10
d
8m range ;
-0 .7 VDC on the 0 dBm range. Th ese voltages Indicate
proper operation of the Meter Board ; while other values,
p
articularly
p
ositive voltages, i ndicate α
d
efective IC or
other problem on
t
he
M
ete r Board .
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