User manual

ManualsBrandsPICO ManualsLaboratory Test EquipmentPC scope module Scope 6402D 250 MHz 8-channel 5 null 512 null 8 Bit Digital storage (DSO), Function generator,

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Toolbars and buttons108

Analog Options. Options that can be applied to

the oscilloscope input hardware, if the oscilloscope

hardware supports them.

DC Offset: an offset voltage added to the analog

input before digitization. For availability, see the

Device feature table.

Bandwidth Limit: a fixed-frequency single-pole

analog filter. This can be useful for rejecting noise

and harmonics that would otherwise cause aliasing.

For availability, see the Device feature table.

Lowpass Filtering. An independent digital lowpass

filter for each input channel, with programmable

cut-off frequency. This can be useful for removing

noise from your signal to make more accurate

measurements. For availability, see the Device

feature table.

7.1.1.1

Resolution enhancement

Resolution enhancement is a technique for increasing the effective vertical

resolution of the scope at the expense of high-frequency detail. Selecting resolution

enhancement does not change the scope's sampling rate, but in some scope operating

modes PicoScope may reduce the number of samples available to maintain display

performance.

For this technique to work, the signal must contain a very small amount of Gaussian

noise, but for many practical applications this is generally supplied by the scope itself

and the noise inherent in normal signals.

The resolution enhancement feature uses a flat moving-average filter. This acts as a

low-pass filter with good step response characteristics and a very slow roll-off from

the pass-band to the stop-band.

Some side-effects will be observed when using resolution enhancement. These are

normal and can be counteracted by reducing the amount of enhancement used,

increasing the number of samples captured or changing the timebase. Trial and error

is usually the best way to find the optimum resolution enhancement for your

application. The side-effects include:

Widened and flattened impulses (spikes)

Vertical edges (such as those of square waves) turned into straight-line slopes

Inversion of the signal (sometimes making it look as if the trigger point is on the

wrong edge)

A flat line (when there are not enough samples in the waveform)

Procedure

Click the Channel Options button in the Channel Setup toolbar.

Use the Resolution Enhancement control in the Advanced Options menu to

select the effective number of bits, which can be equal to or greater than the

vertical resolution of your scope device.