Multichannel Systems MEA1060-Up-BC Manual - Manual (Page 34)

MEA Amplifier with Blanking Circuit for Upright Microscopes
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Important: You can only stimulate during an active TTL pulse , which is used for triggering
the stimulation and the blanking (see illustration of switch positions below). You can switch off
the blanking for test purposes, but this is not considered a useful mode of operation, because
the amplifier will get saturated by the high stimulus input without blanking.
Important: The input voltage of the MEA1060-BC amplifier is limited to +/- 5 V . Exceeding
the voltage input range can result in unpredictable noise and artifacts. In rare cases, even damage
to the amplifier electronics might occur. For current driven stimulation, the voltage amplitude
depends on the electrode impedance. As the electrode impedance depends on several parameters,
for example, the electrode's degree of wear and its hydrophilicity, and therefore cannot be
predicted, it is generally recommended to use
only voltage driven stimulation . Current driven
stimulation may work with larger (30 μm) TiN electrodes that have a low impedance, but this
cannot be guaranteed by the manufacturer.
For more information on the setup, please see the chapter “Setting Up and Connecting
the MEA Amplifier”.
1. Under Stimulation, select a stimulus input (Stim A or Stim B) and click any buttons on
the button array in the MEA layout. Click any electrode that you like to use for stimulation,
for example 23 or 73. The stimulation electrodes are marked by a color, that is, blue for stimulus A
and red for stimulus B. By clicking on one of the selected electrodes again you can toggle back to
recording mode. If you click, for example in Stimulation mode B onto a blue (Stim. A) or grounded
electrode, you overwrite the mode with Stim. B mode. That means, the color will turn to red and
the number of the grounded electrode appears again. If you click for the third time, the selected
electrode toggles back to recording (= default) mode.
2. Click Download to apply the settings. This single stimulation pattern will be repeated
as stimulation pulse until you download a different one.
If you like to download several (up to 50) stimulating patterns, click List Mode. Now you can
create a list of different stimulation patterns. In the small upper window pane the term "New"
will appear and you can change it into the specific name you will give the current stimulation
pattern, for example, Stimulation Pattern 1 = Stim. 1, Stim. 2, Stim. 3. With Update you can
confirm the name and the pattern will be added to the list of stimulation patterns in the left
window pane. Remove eliminates the pattern, which is highlighted in blue. With up or down
you can move the saved patterns in the list to arrange them in that sequence you like to apply
them. To duplicate a saved pattern you have to click the selected pattern, so that it is highlighted
in blue and confirm the same name with Update again. Click Download to send the list of
stimulation patterns to the MEA amplifier.