HP (Hewlett-Packard) 3490A Car Stereo System User Manual


 
SET
SVH
SYVITCH TO IRACK/HOLO.
FUNCTION
TO
OC.
RANGE TO lOV,
A27KI
SHOULO
8€ CLOSED. SET
SAM.
PLE
FATE
FULLY
CLOCKWISE.
APPLY
10 Vdc
INPt T.
II'ITH
SAMPLE/HOLD
SWITCH
SET TO
OFF, VERIFY PFOPER
OC
VOLTH€TER
OPCRATIOITI
OF 34SOA.
CHECK VOLTAGE AT PIN
.I
NEAR TOP
CENTER
OF A27, SHOULO BE NEAR
ZERO.
CHECK WAVEFORMS AT PINS 2
ANO 3 II{
SAME
LOCATIOI{. EXTER.
NALLY
TRIGGER SCOPE ON TEST
FOTNT
K IN LOGIC
S€CTION OF 3ISOA
MAIN
CIRCUIT BOARD. SHOULD B€:
PtN
2
+45
V
HHDA
I U L-OV
nf-l-
üi'"
s€T s/H siltTcH 70 tRAcK/HoLo
oR
ACOUIAE/HOLD.
SELECT TO V RANGE.
AP?LY
lovdc INFUT.
SET
SATPLE
RATE FULLY
CLOCKYVISE.
AZ'K1
SH(ruLD BE CLOSEO.
REMOVE
A27 AND A28. REPLACE
WIB
I'MP€R
EOAROS
A24 ANO A25.
SET
S/H SWITCH
TO OFF. CH€CK
DC OPER.
ATION.
YES
APPLY
FULLf,AI{(
RANGES
IN BOTH
ACOUIRE/HOLD
OP
AnE VOLTAGE /
CORRECN
TROUALESHOOT
/
ctRcutß
tN
A2tut
NOTE
ALL IIMES SHOITT{ APPLY
TO OPTION
0d) INSTRUMENTS
(6OHz
LlilE).
FOR
OPTION O5O, INCREASE
TIMES
BY 20 i.