How to get the Vertical scale of Osilloscope TDS 420A ?

[happybird]

Hellow!
Anyone can tell me how to get the Vertical scale of TDS 420A? i use "TKTDS read waveform.VI" to show the waveform in a Waveform indicator,but the Vertical scale is not the same as the osilloscope. Thanks!

[Odd_Modem]

the waveform preamble has two entries
YOF is the offset, subtract this from the data values
YMU is the multiplier, multiply the difference above by this, then the data is scaled.

[happybird]

excuse me,which VI you mentioned? i use TKTDS read waveform.VI,there's no such entries.

[MichaelChaney]

Hi happybird,

I installed the TKTDS instrument drivers and had a look at the TKTDS Read Waveform.vi. I couldn't find any way to change the scale of the waveform graph. The data displayed should be the same that is measured by the scope. Try running the TKTDS 420 Getting Started VI that is located in:

All functions >> Instrument I/O >> Instrument Drivers >> Tktds4xx VIs >> Application Example VI's

I don't have access to a TKTDS 420 myself, but I hope the example VI displays the correct value. If it does then it is a matter of finding out what is different in your VI. Good luck.