StimTracker Produces High Amp Noise on ANT

Hardware General
1

We have an ANT EEG 128 channel amplifier (asalab) and two Cedrus StimTrackers.

Whenever either one of the StimTrackers (or various StimTracker component combinations) is connected to the amplifier and is drawing power from the power strip that the ANT system is drawing power from, we can no longer record EEG due to high amplitude electrical noise.

The ANT system records normally when the StimTracker is not plugged into the power strip, or any other wall socket.

The one thing we do not have a duplicate of is the “StimTracker for ANT Neuro” male to female adapter boards that plugs into the ‘parallel’ and ‘extra’ ports of the StimTracker.

Any thoughts?

Thanks in advance,

Michael

2

If you do not have “StimTracker for ANT Neuro” signal adapter board, then how is StimTracker connected to your amplifier? Are you using the analog inputs on the ANT Neuro?

3

Sorry, we do have a StimTracker for ANT Neuro signal adapter board, which we are using. We just do not have two of them to test whether or not the adapter board was the problem.

After further tests we have discovered that the noise is all 60 Hz and is coming through the parallel cable into the ANT system. Underneath the 60 Hz noise is perfectly fine EEG. The amplifier works fine without the parallel cable attached to the ANT and StimTracker

In summary:
(1) We have tested 2 stim tracker boxes with the same ANT adaptor
(2) We have tried two different parallel cables
(3) The noise is all 60 Hz.

Thank you!

-Michael

4

Thanks for the follow up. Are you using the Cedrus power supply that came with StimTracker?

Also, please try the following: is the noise present when everything is plugged in and turned on, except that the Stimtracker is turned off at its front panel switch?

5

We are using the Cedrus power supplies that came with the StimTrackers (we have two and we’ve tried both).

The noise is present whether or not the power button is on or off.

Thanks,
Michael

6

Fixed

We bypassed the Cedrus power supply with a 9 volt battery, fixing the noise problem.

-Michael

7

It is worth noting that a newer AC adapter model that we now include with StimTracker also fixes the noise problem with ANT Neuro.

8

Hi Michael,

Would you be willing to share instructions on how you converted the StimTracker to the 9 volt battery? We are currently experiencing the same issue (turns out the “new” models have the same problem) and Cedurs stopped replying to emails. We are going to try converting to 9 volt this week or just send it back and try a different product.

Thanks!

Daniel