Wavetek 3001 Instruction Manual page 66

PILL 3 co nsists of
m
o dules Μ33-2 an
d
M
9
W
. Ι [ is possible
- iliac PILL 3 can b e restored to op eration si mp ly by recall-
braτ i ng per Sectio n 5.3 .7, an d this
s
houl d be attempted
If αdj υττίπςt Μ9W rππι r π 1
(
Π ) has no cf frrrl on tin , M33 2
pin 5 voltage, the ρrιι fιΙαm is in module Μ33-2 ;
h
owever, if
the pin 5 voltage
c
h αnμas but ph ase loc k cannot
b
e estab-
lished, or if the
p
i n 5 voltage cannot be set to within 5 volts
of 0
V,
the t r ou b le is in ιπυ d υΙ e
M
9W . Measure the M33 2
(Leveler ΤΡ (pin 14) voltage . If itα +0 .5 to 5 VDC, the
~ :?trouble is
p
roba bly in mo du le Μ33-2 : h owever, if it
is
c 'ιegreater than 5 VDC, th e trouble is pr obably
in module
M
9W or Μ30-1, Chec k
t
he M30-1 reference trequencies
and
M
9W output level as show n in Ta ble 5-1 to d etermine
which modu le is
d
efecti
v
e.
PLL 5 co nsists of modules Μ 29-2 and Μ 33-2 . With
t
h e
FRED VERN I ER in CA L position,
m
easure the PILL 5
voltage on Μ29-2 pin 6. A
d
ju st Μ 29-2 control ( Β ) for 0 V
on pin 6. Ι1, wh ile adjusting the M29-2 frorn 1 .9 to 21 MHz
t
his voltage does nor move, the problem is in modole
Μ 33-2, If T he voltage ad ςι ,sts, but will not stay Ιπεkεd, τhε
trou ble is in modu le Λ129-2
PH
A
SE-LOC KE D
L OO P 4 - Un lock ing of Ιυπμ 4 may,
under certain conditions . be caused by problems rinogmaling
in the other loops.
T
herefore, loops 1, 2, and 3 shoul
d
b
e
operating
p
roperly before truublesluiciting loop 4 .
U nloc k ing ο1 PLL 4 can be caused b
y defective
m od ules
Μ 172,
M
9W, Μ30-1, Μ 31 Α, Μ 3 2Α . Μ 34, πι cnnnecting
RF ca b les,
Connect α
d igital volt meter to M172 pin 1 . The voltmeter
readi ng s h ou l d be 0 .00 V with the Lever/I ΠdicatOT switc h es
set to 000 MHz, -2 .5 V at 250 MHz. and -5 .0 V at 500
MHz . Connect the voltmeter to M172 pin 8. The M172
volt mete r readi ng should be +5 2ο +8 V at 000 MHz, 0 V
at 250 MHz, an
d
.6 to 10 V α1 500 MHz . If these voltages
are obtained, module
M172 is operating proper ly .
M easur e t he Wide Oscillator signal at module M9W. The
fr eque n cy will
b
e
b
etween 1198 MHz an d 1718 MHz,
d ep en d ing upon
t
he. Lever/Indicator switch setting. If ιΙιe
signal level is as speci f ied in Ta ble 5-1, module M
9W is
pro bab ly op erati ng correctly .
M
easure the 40 comb line at
m
odu le Μ30-1 .
T
he 40 ΜΗτ
h
armonics from 40 MHz To 280 MHz
s
hould tie fairly equal
in
a
mplitude and
t
he level shou ld be as specified in Table
5-1 . Th is level indicates proper op er ation of t he Μ 30-1
mod ule .
M
easu re the 1448 to 1487 MHz signal at module M32A .
Th e exact f requ ency is
d
ependent upon the "MHz" switch
setting. If t h e level is as
s
p
ecifie d in Table 5-1 . the Μ32Α is
operating properly,
5-8
Next, measu re the 10 to 9.001 MHz outpu t of the Μ31 Α
mo dιι le, The <ιυιπυι frequency will he 10 .000 MHz with
the "kHz" switches set r
n
000, and will
d
ecrease το 9.001
ΜΙΙι ωιιΙι fit,- "k ΙΙτ " switehrs sr ι to 999- If the si ηnal ΙeνπΙ
is as τ l+ec ιfί ed in Ta ble 5-1, mnd, λe M31A is operating
properly,
If the output of each of the above modu les is cor r ect, c h ec k
t
he connectors and RF cables connecting
m
odules Μ9W ,
Μ 31 Α, Μ 32Α, and Μ 30-1 to module Μ 34 . C h ec k for +7 .3
V on pin 2, +18 V on pin 3, and -18V on pinil of module
Μ34 . It all input signals and OC voltages to mo dule Μ34 are
correct, but t h e Μ 34 module lamp is on, m od ule Μ 34 Is
p
ro
b
a
b
ly
d
efective,
bu
t the t
r
o
ub
le co
u
l
d b
e ca
u
se
d b
y
mod
u
le M9W .
Α
f
urt her c h ec k of t h e Μ 34 can b e made by monitoring
Μ34 pin 8 wit h α λί gίταΙ voltmeter while stepp ing t h ro ug h
t
he 10 MHz to 520 MHz frequency
r
ange in 10 MHz
ste p s, The voltmeter rea
d
ing should be 0 ±3 V; however,
α
d
efective Μ34 may g ίν e ει voitagc rεad ι nq ο1 12 to 16 V.
LL Vf- R:I NDICATO R
S
W
ITC HE S - Troubles it) the BCD
switch circ uits may
b
e ca used by α
d
efective switch, α loose
or
d ιse ιι gaged switch connector, α broken switc h wire, or,
possibly, α defective MI 15 .
F
ive of the switches utilize four wires
p
lus a ground to
select
d
ειίηηαΙ digits from 0 Through 9. The, 100's MHz
switch uses th ree wires plus ground . since it needs only to -
.
select
d igits between 0 and 5. Α " BCD Tr ut h Table",
αμμΙί;α1) Ια to each of (1ιe six switc h es, is given in Table 5-2.
Suspected switch pro blems can he checked b y
r
eferring to
Τα b1 ίι 5 2 an d
t
he inst rument
W
iring Diagram to determine
wh ic h mo du le
p
ins are groun ded for α
p
articu lar fre qu ency .
F or example, to select α frequency of 200.5000 MHz .
Μ 172
p
i n 3 is grounded by selecting
d
igit 2 on the 100's
MHz switch , and Μ 31 Α pins 2 an d 4 are grounded by
d
igit 5 on ι hε 100's kH z switch,
If only the . 10 MHz programming is in error , the trouble
may ho α
d
efective IC3 in
m
odule Μ 115 ( Model 3002) .
DO
W
N CO NVER SIO N
T
R OUBLE S ( M odel 3002) --
Problen ι s it, ι he down -εοηνersίοιι circuitry (
m
od ules Μ 115
and Λ11 Ο1Ν 8) can cause α variety of problems-
If the instrument op erates properly
f
rom I to 520 MHz,
but not from 1 to 999 kH z, the problem p
ro bably lies in
either
m odule Μ 115 or M
10
W
-8 . Ch eck for
t
he TT L
"t υ rη-on" signal at
p
in 5 of the M 10 W-8 If the signal is
correct !0 V
a
bove 1 MHz, 3 V below 1 MHz), chec k to
see that the RF signal is
b
eing switched to the M115 for
output fre qu encies
b
elow 1 MH z, If the switch is working,
the problem lies in either the M1 15 or α connecting ca b le .
If the instrument
o
u tpu t fr equ ency is 10 MHz h ig her than