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strange readings from ADC 100

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strange readings from ADC 100

Postby Guest » Wed Oct 19, 2005 11:25 am


I'm using an ADC 100 on LPT1, with Picolog v5.12.5, running on an Acer TravelMate 290 laptop with Win XP, SP2, to record data from a Kistler dynamometer / charge amp combo. I've measured the charge amp output using a DVM, and expect baselines at 0V, with peaks and troughs of about -1V to +1V. However, the output from the Picolog bears little resemblance, jumping between 0V and -5V, with some peaks and troughs inverted and transposed to incorrect voltages, and sometimes with a lot of noise. Any ideas what the problem might be?

Postby Ian Redman » Fri Oct 21, 2005 8:45 am

I too am experianceing strange results with the ADC-100. It's been sat on a shelf for almost a year, I've gone to use it today, and when measuring a rectified 5V signal I red -18.08V, the signal reguarly has noise on it, however the signal doesn't seem to change no matter what I connect it to. (unconnected there is just no noise) would be really good if someone for pico has any thoughts on this.


Ian Redman

Postby Sarah » Tue Oct 25, 2005 10:24 am


Thank you for your posts.

It sounds as if you need to use the ADC-100 adaptor for incompatible parallel ports. This adaptor is supplied with the unit.

When you are using this adaptor you will need to tell the computer so that it recognises that it is there. To do this you need to insert the following patch into the win.ini file:


You should insert the patch on a new line and exactly as written above. When you have done this, save the file and exit. The Picoscope software should now recognise the adaptor and report "Use Adapter" in Help | About. The ADC-100 should also now be functioning normally.

Hope this helps

Best Regards

Postby Guest » Tue Oct 25, 2005 1:02 pm

Thanks for this info. The people I borrowed the ADC100 from don't know anything about an adaptor! Can anyone tell me
(i) what the adaptor looks like,
(ii) how to determine whether or not I actually need one (e.g. from LPT1 settings in bios, etc), and
(iii) how to get hold of one if I can't find one here?

Postby Guest » Wed Oct 26, 2005 9:46 am

Not to worry. I've solved the problem by switching to an older computer, running Win98SE, and switching the parallel port mode to 'normal'. ADC100 is now working fine.
Still might need to get an adaptor as this old computer is on its last legs - are they available seperately?

Postby Sarah » Tue Nov 08, 2005 9:37 am


Thank you for your post.

Yes if you contact us by email we can arrange for you to get an adaptor. tech@picotech.com

Best Regards

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