Slow AC voltage measurement readings with hp34401a

Hi,
I am currently using the hp34401a to record an input and output signal voltage (this is then converted programmatically to frequency response). This measurement however I consider to take exceptionally long for what it is (approx 3 seconds per measurement). I am using Configure measurement.vi (set to AC voltage on auto range) and Read(single point).vi. If anyone can give me some ideas how to speed up these readings that would be appreciated.
I have had a look at a similar test done with Labview 6.2.1, where the testing is much faster. The same instrument is being used but with Traditional NI-DAQ.
Thanks
Tania
Note: Labview 8.6

TanWal wrote:
I have tried all the possible/ suggested ways I can think of to improve the reading. There seems to be little that can be done in AC. Even applying the fast filter did nothing to improve the time. I tried to do DC voltage measurement, then take a multipt read and use the Basic rms.vi to obtain an AC value but this is very inaccurate. It seems that this DMM is very limited in its speed for this type of measurment.
I took a look in the spec. Forget the DC way if you have frequencies higher 80Hz....however if you have sampled waveforms do a tone detection (FFT based) or better a SAM (sinus approximation via min MSE) to get the best out of your data ( For FRF with sinus excitation). With RMS measurements you will measure hum and noise too, however you didn't tell us the uncertainty goal nor your DUT.
I don't use this instrument but from the spec and my experience with HPs(agilent) you should be able to get 10 reading/s in AC mode BUT still have to wait for the settling of the AC filter after switching (I assume you use the front and rear input)
I would encourage you to write a small state machine for the task and post it here.
Greetings from Germany
Henrik
LV since v3.1
“ground” is a convenient fantasy
'˙˙˙˙uıɐƃɐ lɐıp puɐ °06 ǝuoɥd ɹnoʎ uɹnʇ ǝsɐǝld 'ʎɹɐuıƃɐɯı sı pǝlɐıp ǝʌɐɥ noʎ ɹǝqɯnu ǝɥʇ'

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Message Edited by Zeyad on 09-13-2007 11:51 AM
Attachments:
Pico_AMP_tests_2.vi ‏125 KB

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“ground” is a convenient fantasy
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Attachments:
Cont Acq&Graph Voltage-Int Clk.vi ‏68 KB

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correct1.jpg ‏2305 KB

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Slow AC voltage measurement readings with hp34401a

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