Spot Frequency - Datron 4708 User Handbook Manual

4708 Frequency
selection
panel
Deselect Store
To
revert to
normal
frequency
facility:
Press the Store key
again
- Its
LED
goes out
-
The F1-F5
LED
goes out
-
The
stored frequency remains unchanged
Re-program
a
Frequency
Memory
Store
To
change
the
Frequency of
a
Memory
Store, the
following
procedure
stores
any
displayable frequency
in
any of
the five
locations:
Select the required
FREQUENCY
RANGE.
Use
the
FREQUENCY
display
1
4-
keys
to set the
new
frequency on
display.
Press
and
hold
the
Store key
-
Its
green
LED
lights
Press
and
release the desire
F1-F5 key
-
Its
LED
lights
-
The
store location
is
also present
on
the display
Release
the Store
key
-
Its
LED
remains
lit
If desired, deselect Store as
above
STORE KEY
-
SUMMARY
Press
and
Release: Access
F1-F5
for stored frequency
re-
trieval.
Press
and
Hold: Allows
displayed frequency
to
be
stored
in
F1-F5 memories
Spot Frequency
This
facility
exists to
provide
rapid access to five user-selected
spot calibrated frequencies
on each output Voltage and
Current
range.
As
there are seven Voltage ranges,
and
five
Current
ranges,
this
makes
a
total
of
sixty spots in
all.
Selecting a
new
OUTPUT
RANGE
also
calls
up
its
five spot
frequencies, ready
for selection.
The 4708
output
can be
calibrated
at
each
spot frequency, thus
achieving
ultra-high
accuracy by
eliminating the
'Flatness'
component
By
using
non-volatile
memory,
these frequencies
and
their
associated calibration constants are retained
in store,
even when
the
4708
is
powered-down.
In order
to
change
the
frequency
setting
of a
spot
and
recalibrate
at the
new
frequency,
it is
necessary to enter
'cal'
mode
(with the
rear panel
CALIBRATION
key-switch
set to
'ENABLE').
The
output
level
span
available for calibration
of Spot
frequen-
cies
is restricted to
within
10%
of nominal
full
range.
The
calibration
procedure
is
described, together with
the other
routine
calibrations, in
Section
8.
4708 Frequency
control
panel
when
used
for the
maniplulatlon of
spot frequency
Spot key
This
reassigns the use of
the
F1-F5
keys,
to
provide
read-access
to
the non-volatile
memory.
Recall
To
set
the
4708
to
one
of the existing spot frequencies,
with
output
as
previously
calibrated,
simply:
Press
and
release the
Spot key
-
Its
LED
lights
-
The
Store
LED
lights
Press
and
release the desired
F1-F5 key
-
Its
LED
lights
-
The
Store and Spot
LEDs
remain
lit
-
The
spot
frequency
is
presented
on
the
FRE-
QUENCY
display,
accompanied by
its
store
location (see
illustration).
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