Dc Current; Ac Current; Resistance; Additional Facilities - Datron 4708 User Handbook Manual

Frequency
Control
Refer
to
pages 3-6
to 3-8.
DC
Current
Use
the
General Sequence:
At
operation
(3)
:
Select
DC
followed by
I
At
operations
(4)
and
(5)
:
Remote
Sense
not avail-
able
N.B.
Maximum
compliance
3V
on
all
ranges except with
Model 4600
Transconductance Amplifier
when
compli-
ance
is
limited
to
2V.
AC
Current
Zero Output
Zero
AC
Current output
from
the
4708 can be obtained by
pressing
the
Zero
key. This causes
the internal
software
to
isolate the
1+ and
I-
terminals
from
the internal circuitry,
physcially interrupting the
Output
Current.
Increment from Zero
The
smallest
AC
output
available
on any
range
is
9%
of
full
range, so
any
attempt
to
reduce
the output
below
9%
is
refused.
Thus
the smallest possible
increment from Zero
is
to
10%
of
full
range, using the appropriate
key
(any
key
to
the
right
of
this
would
attempt
to
increment
to
1
%
or
less,
and be
refused).
Half-
size
zeroes
on
the
Zero
display
show which
keys cannot be used
to
increment
from
Zero;
full-size
zeroes
show
those
which
can.
When
the display
is
correctly
incremented with
OUTPUT
ON,
the
I-i-
and
I-
terminals are internally
reconnected
to
the Current
output
circuits.
Zero Displays
Range
Zero Display
lOOnA Oo.oo
0,0 |lA
1mA
0oo,ooo
mA
10mA
O.ooo.oo
mA
100mA
0o.ooo,o
mA
lA
.Ooo.ooo
mA
lOA
O.ooo.oo
mA
Current
Outputs
To
generate
AC
output
currents,
use
the
General Sequence:
At
operation
(3)
:
select
AC
followed
by
I
At
operations
(4)
and
(5)
:
No
Remote
Sense
N.B.
Maximum
compliance
3V
on
all
ranges except with
Model 4600
Transconductance Amplifier
when
compli-
ance
is
limited
to
2V,
Changing
functions switches
OUTPUT
OFF.
Resistance
Use
the
General Sequence:
At
operation
(3)
:
Select
Q
-
Remote
Sense
LED
lights
as
4708
is
forced
into
4-wire
At
operation
(4)
:
If
2-wire
Ohms
is
required, press
Remote
Sense
to
deselect
At
operation
(5)
:
4-wire
Ohms
-
use 1+ and
I-
terminals for
energizing
current.
Measure
at
Hi and
Lo
terminals.
2-wire
Ohms
-
use
Hi and
Lo
terminals
(1+
and
I-
terminals internally fused
at
l.OA,
Hi and
Lo
terminals fused
at
3.75mA; on
Q
function).
At
operation
(8)
:
RANGE
key
value
is
nominal.
OUTPUT
display value
is
as previously
calibrated
(At Full
Range
only,
for 4-
wire;
at
Full
Range and Zero
for 2- wire).
At
operation
(9)
:
Left
hand
(overrange) pair
of
1
4^
keys
have
the
same
functions as Full
Range/
Zero
keys.
The
other
t ^
keys are inoperative ex-
cept in
Calibration function
(See Section
8).
Additional
Facilities
Frequency
Store
Store
Key
This
key
controls the storage
and
recall
of five user-selected
fre-
quencies.
The memories
are
volatile in that their
contents are
lost
when
the
4708
is
powered-down. At power-up,
the
following five
decade
frequencies are stored automatically.
FI 30Hz
F2 300Hz
F3 3kHz
F4 30kHz
F5 300kHz
ACCESS TO STORED FREQUENCIES
Recall a Stored
Frequency
To
set
the
4708
to
one of
the five stored frequencies, simply;
Press
and
release the
Store
key
- Its
green
LED
lights
Press
and
release the desired
F1-F5 key
- Its
LED
lights
-
The
Store
LED
remains
lit
-
The
stored
frequency
is
presented
on
the
FRE-
QUENCY
display,
accompanied by
its
store
location (see illustration
page
4-10).
Recall
from a
Different
Memory
To
switch
to
a different stored frequency:
Press
and
release the desired
F1-F5
key.
-
The
displayed indications
change
as appropri-
ate.
-9