transients from STG sync output seen in the recording

HI
While I send the Sync output to the MEA from STG, I get transients in my recordings, even when the waiting period is 100microseconds. This could mean that my blanking circuit gives me a transient .And at the same time I am not seeing stimulus artifacts which I am supposed to see while I am not using blanking.

Could anyone help?

thanks

Dear Giresh

> While I send the Sync output to the MEA from STG, I get
>transients in my recordings, even when the waiting period is
>100microseconds. This could mean that my blanking circuit
>gives me a transient .

Our support team is already working on this to support you. I will post the outcome in this forum, too. It could help if you would send us the stimulus protocol (stm file) to our support address (support@multichannelsystems.com).

>And at the same time I am not seeing
>stimulus artifacts which I am supposed to see while I am not
>using blanking.

This is quite strange. Do you mean you switch off the blanking feature in the MEA_Select software, stimulate with a synchronous blanking signal (this is very important, without TTL signal, you get not any stimulation at all), and still do not see any stimulus artifact? If that is true, please use the provided model test cell and make a test experiment. Confirm that the Sync Out signal is synchronous with the pulses and that the BNC connection is fine. What is the noise level you observe? The standard noise level should be in the range of +/– 8 µV (see also the First Tests and Tutorial in the Help/Manual). If the noise level is zero, the amplifier is in saturation. In this case, you would not see any true signal or noise, but only a zero line.

Best regards, Christine