FDU (FIELD DIGITIZER UNIT) QC
The purpose of the FDU test is to make sure that the data collected in the field by geophones in analog form is converted into digital data within the standards.
Daily FDU test values;
1-Whether it is within the standard limits determined by the manufacturer,
2-If there are defective digitizers, it is used to confirm that their ratio is within the acceptable limits according to the contract.
The interface of the FDU test program is as above. The program has been prepared for only 2 different recording systems (Sercel 428XL and Sercel 508 XT). The FDU test file extension for the Sercel 428XL system is in .txt format and is standard(fixed), but the same is not true for the 508XT.
In the 508XT recording system, columns in the test parameter can be changed. Since the FDU program reads on the columns, the values(columns) must be in the order indicated below in order to work stably.
Sercel 508XT FDU test format and order should be as follows.
1-Type
2-Serial Nb
3-Channel Nb
4-Line Name
5-Point Number
6-State
7-Auto Test
8-Easting(m)
9-Northing(m)
10-Elevation(m)
11-Noise
12-Distortion
13-Phase
14-Gain
15-CMRR
16-Version
17-Last Test Date
18-Cx Master
Once the data is loaded, the graphic type can be selected from the "Graphic style" panel. The limits shown with the red line on the screen above are the limits determined by the manufacturer and are not changeable.
If the bar is preferred as a graphic type, the visual will be like on the screen. In the above example, the phase value of FDU has been checked. The error rate of the phase-phase value can be found by clicking the "Error pie" button on the "Control panel".
If you want to check 2 or more tests, the program has ability to check more than one test data. Since the file selection screen allows you to select one test for each time, the screen will open as many as the number of tests and allow you to select multiple data. When the data is plotted, each test result will be colored differently.
GeoTECH - Free Seismic Data Acquisition Quality Control Program