Fluke PM3370B user manual Acquisition Length, Description

5 - 2 FUNCTION REFERENCE

ACQUISITION LENGTH

Description:

The oscilloscope allows the user to select the acquisition length, or record length that best suits the needs of the application. The default acquisition length is 512 data points for each trace. It is possible to increase the length of a trace from 512 points up to a maximum 8K points (or 32K points if the memory expansion option is installed). This results in a trace length of 16 screens, or 160 divisions.

The TB MODE menu offers four choices to select the acquisition length. This menu is accessed via the key sequence ’TB MODE >> ACQ LENGTH >> ..’ Selection of the desired acquisition length is then made with the soft keys as indicated. Note that all registers will be cleared when the length is changed. The user must confirm the change of the acquisition length.

The X POS control is used to move the trace in horizontal direction and to display any desired part. A bar graph shows which part of the trace is displayed on the screen. By using the MAGNIFY key pair, you can expand the trace up to 32 times to look at signal details. The MAGNIFY keys can also be used to compress the signal to fit the display width and look at the total waveform. This is realized without the loss of vertical information.

The 8K acquisition memory is shared between all channels. In the ’2ch@4K pts’ mode the entire memory is used for the two channels, so triggerview of the external trigger channel is not possible.

In the standard mode the trace length is 512 samples and all channels can be acquired simultaneously. In this mode, more traces can be stored in the reference memory, and the screen update rate increases. This mode also supports delayed timebase operation. This way, acquisition can consist of up to eight traces, four Main TB and four Delayed TB traces ( for the 2 channel models: six traces, two Main TB traces, two Delayed Time Base traces and two Trigger View (MTB+DTB) traces).

The following table shows the selection possibilities for a standard oscilloscope with 8K acquisition memory.

Acquisition length	Reference memory	Traces *)
8K	2 registers of 1 trace each	3 (3)
4K	2 registers of 2 traces each	6 (6)
2K	2 registers of 4 (3) traces each	12 (9)
512	8 registers of 4 (3) traces each	40 (30)

*) memory plus acquisition; 2 ch. models between brackets