I am not getting a signal, help

Hi,
I have been using the 8x8 mea cup with MC Rack to record electrophysiological data. I have successfully recorded some data last year. When I tried to use the equipment this time, I could not see any signal on the screen. But upon changing parameters, I found that there is a flat line being recorded in each electrode at - 2 mV level, with the system all connected as it should be.
If I disconnect the cable leading from the platform/circuit board to the computer, the flat line returns to zero.
Additionally, when the signal was running at -2 mV, no amount of manipulation seemed to register a change in the flatness of the displayed line. There was no electrical activity recorded when I did things to the sample that should have it jumping all over the place (excessive stimulation). I tried two different samples for this: one a cell culture, another a slice culture. There was absolutely no electrical activity recorded even if I touched the ground wire!
What do I do? What am I doing wrong? I am following exactly the same procedures that I did last year, when I got data. I even had the latest version of MC Rack downloaded to the computer before recording.
Please help!
Thanks,
Ash

Dear Ash,

can you provide us with some more details? What system are you using exactly (blanking circuit?), are you working with the test model probe?

Before you start trying to record from biological samples you should be able to get a stable baseline when you just use the test model probe. This will help to check the amplifier and connections (such as proper grounding).

If you are working with a BC amplifier please check settings in MEA Select software and note that the baseline restoring can take 1-2 minutes.

If a minor offset persists you might want to use the offset correction under "Hardware".

If you want to provide us with serial number, photos, screenshots etc please use support@mulitchannelsystems.com

Greetings

Thomas

Could you check the output power of the 68-pin socket on the back of the data acquisition computer? Pin layout is in the MEA System User Manual or MC_Card data sheet.

If you are not recording any signal at all, there is probably a problem with the IPS10W power supply in the computer. You could also open the computer and check whether the IPS10W is still properly plugged into the MC_Card.

Please send us the serial number of the MC_Card and amplifier to our support adress. Did you change anything on the setup?

Best regards, Christine