Subject: Re: TDT system 2 users From: "Marvit, Peter" <PMarvit(at)SOM.UMARYLAND.EDU> Date: Mon, 13 Sep 2004 09:01:34 -0400Several years ago, I also discovered distortions in generated signals from the System 2 D/A unit when creating signals that were at or near the full range (~ +/-9V output), with or without the anti-aliasing filters. The issue seemed to be resolved by limiting the output to +/- 5V or less. Unfortunately, I neither reported nor followed up on the problem then. I have been using the System 3 modules for the past two years (RP2 and RX6) and have encountered no such distortion problems up to 100K sample rate. It should be noted that the RP2 and RX6 use different DA converters from the old RP2 modules. In any case, and with *any* hardware, I echo Ken's observation that stimuli should be very carefully tested during experiment development and should never be "assumed" to be correctly generated without adequate verification. Cheers, Peter : Peter Marvit, PhD <pmarvit(at)som.umaryland.edu> : : Dept. Anatomy and Neurobiology University of Maryland Medical School: : 20 Penn street, HSF II, Room S251 Baltimore, MD 21201 : : phone 410-706-1272 fax 410-706-2512 :