4 – 10
Remote Operation
Reference output amplitude
SLVL(?)
{
g
}
Set (query) the reference oscillator output amplitude
{
to
g
}
, in volts
RMS. The default value is
SLVL
0.100
.
Allowed values for
SLVL
may be restricted if the DC Bias is enabled.
See section 3.4 for details.
SLVL 1.5E-6
Example:
Reference slope shape
RSLP(?)
{
z
}
Set (query) the external reference input slope mode
{
to
z
=
(
SINE 0
,
TTL 1
)
}
.
RSLP
is used to configure the external reference input trigger circuit.
When set to
RSLP
SINE
, the Ext. In BNC input is AC-coupled to a
discriminator circuit armed to trigger on positive-going zero cross-
ings. When set to
RSLP
TTL
, the Ext. In connection is DC-coupled,
and the discriminator looks for positive-going transitions crossing a
+
1 V threshold, compatible with TTL and CMOS logic.
RSLP SINE
Example:
Reference oscillator range
FRNG(?)
{
z
}
Set (query) the reference oscillator range
{
to
z
=
(
FRNG P2 0
,
FRNG 2
1
,
FRNG 20 2
,
FRNG 200 3
,
FRNG 2K 4
)
}
.
In all modes, the oscillator range
FRNG
must first be set to the cor-
rect span for the desired
oscillator
frequency. If operating in one
of the harmonic modes (
FMOD
EXT2F
or
EXT3F
), the
FRNG
setting
must span the harmonic frequency, which may not necessarily in-
clude the (lower) external input frequency. For example, if operating
in second harmonic mode (
FMOD
EXT3F
) and the external input is
1.5 kHz, the oscillator will lock to 4.5 kHz and the range must be
set to
FRNG
FRNG 200
or
FRNG
FRNG 2K
; it will
not
lock if set to
FRNG
FRNG 20
.
Each range spans 2 decades, and overlaps its adjacent ranges by one
decade each:
z
Value
Frequency Range (Hz)
FRNG P2 0
0.2 – 21
FRNG 2 1
2 – 210
FRNG 20 2
20 – 2.1 k
FRNG 200 3
200 – 21 k
FRNG 2K 4
2 k – 210 k
FRNG 3
.
Example:
SR124
Analog Lock-In Amplifier
