Ericsson 9D902780G3, Maintenance Manual, Page: 5 / 12

PARTS LIST
SYMPTOM CHECK
(CORRECT READINGS SHOWN)
INCORRECT READING INDICATES
DEFECTIVE COMPONENT
SYNTHESIZER FAILS TO LOCK Check DC voltages
+5 V @ U301 Pin 1
+8 V @ Q301 collector
-5 V @ U303 Pin 1
U301 or associated components
U302, Q301, Q302 or associated
components
U303 or associated components
Check 12.8 MHz reference signal
3V P-P, 12.8 MHz @ U402 Pin 2 No reference signal to front panel BNC or
Q401
Check oscillator signal
11.5
±
1.5 dBm 435 to 485 MHz at
front panel BNC
Proceed to "Low/No RF output" below
Check prescaler output
IV P-P, 3.5 MHz @ U401 Pin 4 U202, U401
Check CLOCK, DATA, ENABLE
While loading frequency data into
synthesizer Check 8V logic signals
@ Pins 11, 12, 13 of U402 Wrong address or
U701, U702, Q701, Q702, Q703
Check Phase detector output
6.25 kHz random signal @ U501
Pin 7 U402, U501
Low/No RF Output Check oscillator
LESS than 0.5 Vdc @ collector of
Q101 Synthesizer not keyed (low on ANT relay
line) or Q101, Q102
Check RF chain
No Modulation Check AF amplifier
Apply IV, 1 kHz signal to
TX/Audio/Hi U601
Check IV signal @ U601 Pin 1
TROUBLESHOOTING GUIDE
UHF TRANSMITTER SYNTHESIZER MODULE
19D902780G3, G6 - G9
ISSUE 5
*COMPONENTS, ADDED, DELETED OR CHANGED BY PRODUCTION CHANGES
SYMBOL PART NO. DESCRIPTION
TRANSMITTER SYNTHESIZER BOARD
19D902779G3, G6 - G9
- - - - - - - - - MISCELLANEOUS - - - - - - - - -
2 19D902508P4 Chassis.
3 19D902509P2 Cover.
4 19D902555P1 Handle.
6 19A702381P506 Screw, thread forming: TORX, No. M3.5-.6 x 6.
7 19A702381P513 Screw, thread forming: TORX, No. M3.5 - 0.6 X 13
11 19A702381P508 Screw, thd. form: No. 3.5-0.6 x 8.
12 19D902824P1 Casting.
- - - - - - - - - - CAPACITORS - - - - - - - - -
C1 19A702236P25 Ceramic: 10 pF + or -.5 pF, 50 VDCW, temp coef
-30 PPM/
°
C.
C2 19A702236P32 Ceramic: 18 pF + or -5%, 50 VDCW, temp coef 0 +
or -30 PPM
C3 19A702236P28 Ceramic: 12 pF + or - 5%, 50 VDCW, temp coef 0
+ or -30 PPM.
C4 19A702236P1 Ceramic: 0.5 pF + or - pF, temp coef 0
+ or - PPM/
°
C. (Used in G8).
C4 19A702236P8 Ceramic: 1.5 pF + or -.25 pF, 50 VDCW.
(Used in G3, G6, G7)
C5 19A702236P13 Ceramic: 3.3 pF + or -5%, 50 VDCW, temp coef 0
+ or -30 PPM. (Used in G3).
C5 19A702236P17 Ceramic: 4.7 pF + or -5%, 50 VDCW, temp coef 0
+ or -30 PPM. (Used in G6 & G8).
C5 19A702236P15 Ceramic: 3.9 pF + or -.25 pF, 50 VDCW, temp
or -30 PPM/
°
C. (Used in G7 & G9).
C6 19A702236P28 Ceramic: 12 pF + or - 5%, 50 VDCW, temp coef 0
+ or -30 PPM. (Used in G8 & G3).
C6 19A702236P30 Ceramic: 15 pF + or -5%, 50 VDCW, temp coef 0 +
or -30 PPM/
°
C. (Used in G6 & G7).
C6 19A702236P32 Ceramic: 18 pF + or -5%, 50 VDCW, temp coef 0
+ or -30 PPM/
°
C. (Used in G9).
C7 19A702061P99 Ceramic: 1000 pF + or -5%, 50 VDCW, temp coef 0
+ or -30 PPM/
°
C.
C8 19A702052P14 Ceramic: 0.01 uF + or - 10%, 50 VDCW.
C9 19A705205P6 Tantalum: 10 uF, 16 VDCW; sim to Sprague 293D.
C10 19A134227P5 Variable: 1.5 to 14 pF, 100 VDCW.
C11 19A705205P2 Tantalum: 1 uF, 16 VDCW; sim to Sprague 293D.
C12 19A702052P14 Ceramic: 0.01 uF + or - 10%, 50 VDCW.
C13 19A702061P99 Ceramic: 1000 pF + or -5%, 50 VDCW, temp coef 0
and
+ or -30 PPM/
°
C.
C14
C15 19A700004P2 Metallized polyester: 0.1 uF + or - 10%, 63
VDCW.
C16 19A702061P73 Ceramic: 330 pF + or -5%, 50 VDCW, temp coef 0
+ or -30 PPM/
°
C.
C17 19A702061P99 Ceramic: 1000 pF + or -5%, 50 VDCW, temp coef 0
+ or -30 PPM/
°
C.
C18 19A705205P2 Tantalum: 1 uF, 16 VDCW; sim to Sprague 293D.
and
C19
C101 19A702061P99 Ceramic: 1000 pF + or -5%, 50 VDCW, temp coef 0
+ or -30 PPM/
°
C.
C102 19A705205P2 Tantalum: 1 uF, 16 VDCW; sim to Sprague 293D.
C103 19A702061P99 Ceramic: 1000 pF + or -5%, 50 VDCW, temp coef 0
+ or -30 PPM/
°
C.
C201 19A702061P61 Ceramic: 100 pF + or - 5%, 50 VDCW, temp coef 0
+ or - 30 PPM. .
SYMBOL PART NO. DESCRIPTION
C202 19A702061P99 Ceramic: 1000 pF + or -5%, 50 VDCW, temp coef 0
+ or -30 PPM/
°
C.
C203 19A705205P2 Tantalum: 1 uF, 16 VDCW; sim to Sprague 293D.
C204 19A702061P61 Ceramic: 100 pF + or - 5%, 50 VDCW, temp coef 0
and + or - 30 PPM.
C205
C206 19A702061P99 Ceramic: 1000 pF + or -5%, 50 VDCW, temp coef 0
+ or -30 PPM/
°
C.
C207 19A705205P2 Tantalum: 1 uF, 16 VDCW; sim to Sprague 293D.
C208 19A702236P28 Ceramic: 12 pF + or - 5%, 50 VDCW, temp coef 0
+ or -30 PPM.
C209 19A702236P10 Ceramic: 2.2 pF + or -2.5 pF, 50 VDCW, temp
+ or -30 PPM/
°
C. (Used in G3, G6, G7, G8).
C209 19A702236P8 Ceramic: 1.5 pF + or -0.25 pF, 50 VDCW, temp
+ or -30 PPM/
°
C. (Used in G9).
C210 19A702236P28 Ceramic: 12 pF + or - 5%, 50 VDCW, temp coef 0
+ or -30 PPM.
C211 19A702061P61 Ceramic: 100 pF + or - 5%, 50 VDCW, temp coef 0
and + or - 30 PPM.
C212
C213 19A705205P2 Tantalum: 1 uF, 16 VDCW; sim to Sprague 293D.
C214 19A702061P99 Ceramic: 1000 pF + or -5%, 50 VDCW, temp coef 0
+ or -30 PPM/
°
C.
C215 19A702061P61 Ceramic: 100 pF + or - 5%, 50 VDCW, temp coef 0
+ or - 30 PPM.
C301 19A702061P99 Ceramic: 1000 pF + or -5%, 50 VDCW, temp coef 0
+ or -30 PPM/
°
C.
C302 19A702052P14 Ceramic: 0.01 uF + or - 10%, 50 VDCW.
C303 19A705205P2 Tantalum: 1 uF, 16 VDCW; sim to Sprague 293D.
and
C304
C305 19A705205P7 Tantalum: 10 uF, 25 VDCW; sim to Sprague 293D.
C306 19A705205P2 Tantalum: 1 uF, 16 VDCW; sim to Sprague 293D.
C307 19A705205P6 Tantalum: 10 uF, 16 VDCW; sim to Sprague 293D.
C308 19A702061P99 Ceramic: 1000 pF + or -5%, 50 VDCW, temp coef 0
and
+ or -30 PPM/
°
C.
C309
C310 19A705205P6 Tantalum: 10 uF, 16 VDCW; sim to Sprague 293D.
C311 19A705205P2 Tantalum: 1 uF, 16 VDCW; sim to Sprague 293D.
C312 19A702061P99 Ceramic: 1000 pF + or -5%, 50 VDCW, temp coef 0
+ or -30 PPM/
°
C.
C313 19A705205P6 Tantalum: 10 uF, 16 VDCW; sim to Sprague 293D.
C401 19A702052P14 Ceramic: 0.01 uF + or - 10%, 50 VDCW.
C402 19A702061P99 Ceramic: 1000 pF + or -5%, 50 VDCW, temp coef 0
+ or -30 PPM/
°
C.
C403 19A702052P14 Ceramic: 0.01 uF + or - 10%, 50 VDCW.
thru
C405
C406 19A702061P99 Ceramic: 1000 pF + or -5%, 50 VDCW, temp coef 0
+ or -30 PPM/
°
C.
C407 19A702052P14 Ceramic: 0.01 uF + or - 10%, 50 VDCW.
C408 19A702061P99 Ceramic: 1000 pF + or -5%, 50 VDCW, temp coef 0
+ or -30 PPM/
°
C.
C409 19A705205P6 Tantalum: 10 uF, 16 VDCW; sim to Sprague 293D.
C410 19A702052P26 Ceramic: 0.1uF + or - 10%, 50 VDCW
C411 19A705205P6 Tantalum: 10 uF, 16 VDCW; sim to Sprague 293D.
C412 19A702052P14 Ceramic: 0.01 uF + or - 10%, 50 VDCW.
C413 19A702052P108 Ceramic: 0.01 uF + or -10%, 50 VDCW.
C414 19A702061P69 Ceramic: 220 pF + or -5%, 50 VDCW, temp coef 0
+ or -30 PPM/
°
C.
C501 19A705205P2 Tantalum: 1 uF, 16 VDCW; sim to Sprague 293D.
C502 19A705205P2 Tantalum: 1 uF, 16 VDCW; sim to Sprague 293D.
C503 19A702052P33 Ceramic: 0.1 uF + or -10%, 50 VDCW.
C504 19A702061P99 Ceramic: 1000 pF + or -5%, 50 VDCW, temp coef 0
+ or -30 PPM/
°
C.
LBI-38671
4