Instructions

Operator’s Manual

Operating with Teledyne LeCroy Oscilloscopes

When the AP033 probe is connected to an oscilloscope equipped with the ProBus

interface, the displayed scale factor and measurement values will be adjusted to account

for the effective gain of the probe. The probe gain, internal attenuation, and offset can be

conveniently controlled through the oscilloscope’s user interface.

In X-Stream software versions, the AP033 dialog appears behind the Channel dialog. The

probe coupling, gain control type (Auto or Manual), attenuation, and gain are all set here:

Figure 5, AP033 probe dialog with probe controls and attributes.

NOTE: In legacy software versions 7.4 and later, probe controls can be found on the

oscilloscope COUPLING

menu. On legacy versions before 7.4, all these settings are

controlled through the physical buttons on the probe body.

There are two modes of gain control: Auto and Manual.

Auto Gain Control

The oscilloscope defaults to Auto mode when the probe is first attached. In Auto mode,

the oscilloscope VOLTS/DIV knob controls the oscilloscope’s scale factor, while the

OFFSET knob controls probe offset. AP033 gain and attenuation are set automatically to

give the full available dynamic range: 200 μV/div to 1 V/div (without external attenuator),

or 2 mV/div to 10 V/div (with external ÷10 attenuator installed). Some of the transitions

in scale factor will result in a change of the attenuation in the AP033 probe. The common

mode range, input capacitance, and noise level of the probe will change with the probe

attenuator setting. For Volts/Div settings which can be produced with more than one

combination of probe gain and attenuation settings, Auto mode selects the combination

which results in greater common mode range and lower input capacitance.

NOTE: In this mode, you cannot control the probe using any of the buttons on the probe

body, only the oscilloscope touch screen and front panel.

Manual Gain Control

In some situations, you may wish to select probe settings optimized for the lowest noise

performance with lower common mode range. Likewise, you may require that the probe

not change input capacitance, noise, or common mode range as you change the

VOLTS/DIV setting. These requirements can be met by setting the probe to Manual gain

control mode. When set to Manual mode, the dynamic range of the VOLTS/DIV knob is