Troubleshooting - GE MASTR II Maintenance Manual

STEP I • QUICK CHECKS
,---- ---
METER
PROBABLE DEFECTIVE
STAGE
POSITION HIGH METER LOW METER ZERO METER
GE TEST SET READING READING READING
EXCITER
A Ql02, 10- Ql02, CVlOl, ICOM, QlOl, UlOl, 1101,
(MOD-I) Volt 1101, 10-Volt Ql02, CRlOl, 10-Vol t
regulator regulator regulatol.· or Channel
Selector switch ground,
B Ql04, 10- Ql03, 1102, Ql03, Ll02, CV102, 1103,
(MOD-2) Volt 1103, CV102
1
CV103, CR104, Ql04
regulator CV103, Ql04
c QlOS, Ql06 QlOS, QlOG Ql05, Ql06, TlOl
(MULT-1) TlOl
D Ql07, T104 TlOl, Tl02, TlOl, Tl02, Tl03, Ql07,
(MULT-2) Tl03, Ql07 Tl04
F QlOS, Tl06 Tl04, Tl05, Tl04, Tl05, QlOS,
Tl06
(MULT-3) Ql08
G Ql09,
Cl46, Tl06, Tl07, Tl06, Tl07, Tl08, Ql09,
(AMPL-1) Rl44 TlOS, Ql09, Llo4, 1107
1108
POWER AMPLIFIER
"D'" Low Output No output from Exciter,
(AMPL-1 DRIVE) from Exciter CR20l
"C" Q210 Q210 No Exciter output,
(AlllPL-1 POWER Q210, Q204, CR20l
CONTROL VOLT-
AGE)
"F"
Q202 Q202,
Low
Q202, Q201, Check
(DRIVER OUtput from Pos.D&C
CURRENT)
Q201
"G" Q203 Q20l, Q202, Q203, Q202, Q20l,
(PA CURRENT) Q203 Q210
STEP 3
CHECK AUDIO AC VOLTAGES
f'QUIPMEI<T 'l'::O~'ri[i)
e AUDIO OSC 11.I.ATOP
• AC VTVM
STEP 4
AUDIO S OSC WAVEFORMS
EQUoP~ 1 E"JT REQ~If'CO
e
A'JDIO OSCILlATOR
e OSSilLO~CC?E
50 AU')oO USCIL_A.,.OR
~T ::JOG 1<7 WITCI
C1ITFUT [)f : C '/ Co~\S
NOTE. AN R~~<; OP i'CJ\K
~E,\L·ING "t:LT MEH'l
Wll~ RU.D 1/2 TO .Jj
OF O;O.',K·iO-FE,\K
'lE.C.CINSS
;;r.oP~
~ E; li'IB
r---
('.33 -If:\. f. I
M>jZ
- + - - - - - - - - - - -
I~
;MISM -TER
@
AUC,O .C
I JI02
MOO 1
AOJJST I
:0---"-"T 7 -l.-
-~
___fit---
If""
I
I
/
/
/
~CII6
AC-VTVM
!OO~V P-P I.IV P-P
ICUM FI-IEI.l'
l'~~
TO
lf'.P-~KZ
46 MV RMS 0.36V RMS
r ~;~')UE'ICY
I
r1
'/l':lER
(74)
STEP 2
MOD
AMPL-1
0102
CHECK TYPICAL DC VOLTAGES
F.C:t.!'PMlNT REQUIR[O
• CJ.[. O~CT MC'bfl. 4FX3!\ol
"
e
20,CoJO Jlll,l-Pth-VJU MUEF.
N(.'~'i:' ALL DC Rl".C.Cir.;s T'-.KErl '.I'IIH
OHE TRANSMIT:ER KE''l:~.
MOD
AMPL-2
0103
TYPICAL MOD-o
REAO>N~
AT
POS. A SHOULD BE'
, 0.5V
L_j
2..0~ -4.1?Mi-'Z
V-DC
TYPICAl MOD-2 REACI.'!(, "-1 ,
I"P20~s,. ~"'-"'""''""'""' ---~,
0.5V
I
MOD
AMPL-3
QI04
MOC-2
BUFFER
0105
J IC•3-I
(POSITION 8)
V-DC
.~-----J.--------
f 25-12.5 M flZ
~-------t~------·>2
5-25 MHZ
~------1----------- - ----~-- --- - -·---------------~
?5-50 MHZ
MULT-I
TRIPLER
0106
/
'
J'l
Ml.Jli-1
1 1 JI03 3
iP0SITIOI'. C)
TYPIC'Jl~ M'JlT 2 PEAOING J\T
POS. D s~OJ r 8[.
0.56V
·---
- - - - -
MULT-2
DOUBLER
0107
V-DC
-~--
'TYPICAL 1/IILT-3 RE'ID'NG AT
~O_S~ ~ SI 1 0ULD
BF.
:o.-"sv
L_ _ _ _ _ _ _
MULT-3
DOUBLER
0108
'TY":Oo\l ,U,IPL-1 ROAn lNG
POS. G SloO~L;) BE
0,3V (~b-50M~ZI
:o.5V (25·3EMHZ1
'
L -
---
v-oc
AMPL-1
0109
, TYDICIIL ,IMPL I READIN~S JlT
oPOS. 0 '01--<0ULil 80:'
~·-~o
MHZ 0.5V 125 WHZ)TD
~~
:_________
Q-~~'{1~0~
30-'%MH7 O.GV i:OD.'$HZITO
0.5V (;,G MIIZ)
: 3G-42 MKl!
8·.~~ ~~~~~~~~iTO
4~-'\0 ~·Hz> 0.65VI42
MHZ)TO
'0.5V I~OMHZ)
--~·='--
[POIIIER CUTP'JT'
·
2~0 ~~W
MIN
°
AMPL-1
0201
~ J_/.MO'L-1 ~RIVE
v2C.5-4
iPC::S.T.O.~
C)
~~
/
(
/
V-DC
TYr 1 CA~ AM?L-1 READING AT
POS. C S•IOIJ~C' ~E-
1
0.45V TO
10.75V
VOLTAGE • VQ, lAO~ R~ADING
' "
DRIVER
0202
v-oc
lYPICo\1_ DF'IVER lc R<:ADI~G AT'
POS. f SHCU' 0 BL· '
-:~~--'3C'~IHZ
:0.3V I<!5MiiZ)TQ
_ _ _ _ _ j.Q.J7Vi~OMHtl
,3Q- 3 GMHZ 0.25V13CM>jZ)TC
• 0.2V 136MiiZ:
'36· 4;;;;-;_ 0.25V i3P-MIIZ\ T')
~ __ Q.2V 142~1-'ZI
42 O'lMdZ 0.25V<4~MHZITO
0.'2V ('Y'MHZ)
,.,.,,<,<"'-'"'"'"''0-C'_C_O_>_"~!\~N-,-:
- 2.JQ__ - - - - - - - '
PA
0203
?;. CI.IRRi.!>!T
J205 6:-+j
JZC5· 5 :-:
IPOSITIO~
G)
TO +12.t>V r
V-DC
TYPICAL O<EAD'NG AT
POS. G SIIO~JLO BE"
2~·3CI,"~Z g:~§~:~;~~~~;~v:
3U-56MHZ 10.8V (30MHZHO
1 0.7V 136MHZ)
36 4 2MHZ 0.75VI38MIIZ)TO
0.65V (4~fit1Z'
142
5~/.'HZ 0.7V
142MII7:T0
1 0.6V (50~HZ)
l
co;I>RF.:.IT• VOLT!\C.f REAOING
- ____ ,_r;;- - - - -
LBI-4896
"'
SWITCH:
J2CI
/I.NI
TROUBLESHOOTING PROCEDURE
25--50 MHz, 50-WATT TRANSMITTER
Issue 1 11