HP Car 3490A manual Start, 9 0 D- 3 3 8

START

BEMOVE ASCII INGUAFD A $ EMALIES Ag AND 436 . INSTALL REMOAEJUMP, EF BOAFD 44 ISUPPLIEDWtTB OPTION OSI IN CONNECIOR A1J7 IN PLACE OF AS. SET 34SA RANGE ANO FUNC- TION TO TEST i TO VEFIFY COFFECT OPERATIONOF MAIN LOGIC .

FEMOVE A4 ANO REPLACE Ag AND 436 . MESURE + 12 V . + 5 V, ild - 2 V

OUTGUAND VOLTAGES . +I2V AND

. 2V AEST POINTS ARE ON A32 AND +5V TEST POINT IS ON A33 . VOLT .

AGES MUST BE MESURED TO OUT. GUAAD GFOUND TEST POINT ON 433 OR A3O. ALLOW +/,1ü TOLLEflANCE.

ARE VOLTAGES CORRE

TFOUBLESHOOT OUTGUART AGE SUPLIES . +12V . d +

PLIES ARE LOCAT€D ON OU MOTHEF EOAFO A3I . . 2 V SI trVELOPED FROM SYSTEM MULTIVIBAATOF ON A32,

M E N U R E + 1 2 V A N O . 2 V S U P P L i E S

q IilGUARO ROM SEMBLY A34. THESE AR€ ON TEST POINTS ON A34. MENURE TO INGUAFO GROUNO AT EST POINT ON AS,

TROUBLESHOOT SUMLIES

GUARD FOM A$EMBLY AA.

CHECK OPEAATION

OF

ISOLATING

THIS CHECK A$UMES

THI

PHOTO.TFANSISTOAS

U1 THAOUGH

UII

WIIH

A

LOGIC PROAE OR AY

ONE GPIBPRINTED

CIFCUT

CONNECTING A KNOWN GOOD UNIT IN

ALY IS DEFECTIVE . USINC

PARALLEL

WITH

THE

SUSPECTED

ELIES

IN

GPIB

REPAIR

PHOTO.TRANSISTOB

IN

THE

g9OA.

OAS8m.

SUBSTITUTE A$

A60

CHECK

DFIVE

TRANSISTOFS

ONE AT A TIME IN THE FO

AM4

THROUGH

@

AND

A35OI

OROEB: A32, AS.

A36, A34,

THBOUGH 04 . *

Note l .

LATION

NS € MELIES

A3O,

TOGETHER .

AFTER

SUS'

ffi

EACH

ASSEMBLY,

PERFO

PROBLEM lS CLEARED, Se

No

OPEFATING CH € CK GIVEN

FEPUCE DEFECTIVECOMPONENT .

GNAPH 5.7 OA '9 IO

DETE

6E CAFE IN HANOLItrG ISOLATION

NEMBLIES,

PHOTO,TRANSISTOAS U 1

DROUGH !II AAE VERY S € NSITIVE

TO MECHAtrICAL STRE$.

ilotEs:

1 . THE ISOLATING PHOTO - TRANSISTOBSU1 _ II MAY BE CHECKED BY CONNECTINC A NEW PABT IN PAFAL . L € L (ALL FOUR CONNECTIONS) WITH THE SUS - PECTEO PAAT. THE NORMAL VOLTAGE OROP ACFO$ THE DIOOE POATION OF THE PHOTO . TßANSISTOF

UNIT SHOULD BE APPAOXIMATELY I - 75 V WHEN THE UNIT IS BIASED ON, ASL4 _ 9 AND A35L1 5 ARE FERRIT € 8EAN .

2, EACH TIME AN SSEMALY OR PAFT ISSUBSTITUTEO OR A REPAIF IS MAOE, THE OPEBATTONOF THE GPIS CIACUITSSHOULO 8E CHECKED USING THE PEAFOF - MANCE CHECK IN PARAGRAPH 545, THE COMPLETE CHECK MAY BE BUN, OA ONLY THAT PORTION WHICH THE INSTRUMENTFAILEO PREVIOUSLY .

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