Some RA16PA and RA4PA generate a 3 kHz noise that masks neural activity

Tech Note: TN0067
Product: RA16PA, RA4PA
Version: Serial numbers < 3000
Date Added: 2002-12-17

Issue

Some RA16PA and RA4PA with serial numbers < 3000, generate a 3 kHz noise that masks neural activity.

Solution

The voltage regulation on the preamplifiers has been modified to provide better control of voltage variation. The preamplifier has also been modified so that low battery voltage is indicated earlier. This 3 kHz noise artifact is not generated on all headstages with all electrodes. We recommend updating to the new preamplifiers only if your system generates this noise.