YSI SonTek ADVField, Technical Documentation Manual

Page: 161 / 228

SonTek/YSI
ADVField Software Manual (September 1, 2001) 29
Section 5. Analog Output Calibration (ADFCALAO.EXE)
All ADVField systems generate analog output voltages. The analog outputs include three lines
for the three velocity components, and one line proportional to the mean signal amplitude. Sam-
pling these voltage lines with an external analog data acquisition system provides an alternative
means of recording ADV data. When possible, we recommend using the digital velocity data as
this provides improved resolution (avoiding a digital-to-analog-to-digital conversion) and addi-
tional diagnostic data (three signal amplitude and three correlation values). See the
ADVField
Operation Manual
for detailed information about the analog output voltages.
The ADV software includes a program (
ADFCALAO.EXE
) for calibrating the analog output volt-
ages. Calibration of the analog outputs is required to compensate for minor changes in the output
voltage levels caused by cables and temperature fluctuations. To run the calibration program,
type the following command at the DOS prompt.
ADFCALAO [com port]
The
[com port]
parameter is the communication port to which the instrument is connected
(1 for COM1, 2 for COM2).
ADFCALAO
accesses the ADV and forces all analog outputs to their low, mid, or high-level volt-
ages. The low voltage corresponds to maximum negative velocity; mid to zero velocity; and high
to maximum positive velocity. The operator sets the level by simply pressing the L, M, or H key.
After pressing one of these keys, the program will set the analog outputs of the ADV to the cor-
responding level, so the actual output voltage can be measured by a data acquisition system or a
precision voltmeter. See
ADVField Operation Manual
for details on applying the output voltage
calibration.
To exit the program, press <Esc>.