Fluke 93 Service Manual page 63

CIRCUIT
DESCRIPTIONS
3-29
METER
0/ -N-
modes
Sr1a Sr2a Sr3a Sr4a
SgndBb
Srib
CO Sr3b Sf4b
'
SgndSa
mV
OHM
300
Ohm
0
0 0
t
1
0
0
D
1 1
0
D
3
KOhm
D
0 0
1
1
D
0
D
1 1
0
1
30
KOhm
D DD
1 1
D
0
0
1
1
D
1
300
KOhm
O
0
O
1
1
0
0 0
1 1
0
1
3MOhm
0
0 0
D
1
0
0 0
1 1
0
1
30
MOhm
D
0
0
D
1
0
1
0
1 1
D
1
Diode
0 0 0
D
1
0
1
0
D
1
0
1
Scl5 Scie Sc17 Scia
300
Ohm
a
0
1
1
3
KOhm
1
D
1
D
30
KOhm
1
0
0
0
300
KOhm
1
1
0
0
3
MOhm
D
1
D D
30
MOhm
D O a
Diode
—
"I
1
0
1
1
BUZ
Buzzer
off
1
Buzzer on
0
G.OUTP
Ext. Trig.
0
Generator
1
SCOPE
mode
Attenuator
settings
METER
mode
>
20 mV/dlv
5
lOmV/dlv
D-POSCHA
0
1 1
D-POSCHB
1 1
X
While the
Scope Meter
Is
operating
In
METER
mode
or
when
the Instrument
Is
calibrated,
the signals
SI,
mV,
OHM,
Srib, Sr2b, St3b, Sr4b,
and
D.POSCHB
can
change
("hlgn/tow").
signals
Ex and Ey
are
used
to
switch the
relays.
Both signals
are
"high*
when
the relays are not operated.
Signals Sg4a, Sg5a, Sg6a,
and SgTasetthe
LF.
gain
for
channel
A.
Sg^,
SgSb, Sg6b,
and Sg7b
set the
LF.
gain
for
charnel
B.
(Sg4b)
Is
the
most
significant
bit
(MSB),
Sg7a
(Sg7b)
Is
the least
slgr^lf
leant
bit
(LSB).
Signals
Sol
Ob,
Sot
1b,
SOI
2b,
Sol
3b,
and
So
14b are used
to
set the
offset
compensation
In
the
preamplifier
circuits
of
channel A. Signals Sc15, Sc16,
Sc
17,
Sc18, and
SO
14a are
used
to
set the
offset
compensation
in
the preamplifier
circuits of
channel
B.
SOI Ob (Sets)
is
the
most
slgr^flcant
bit
(MSB), Sol
4b
(Sol 4a)
is
the least significant
bit
(LSB).