Molecular Devices Axoclamp 900A, User Manual

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Setup and Tutorials
The Headstage 1 Membrane Potential passing through a pre
‐
determined level. The direction it passes through the level is also
programmable (negative to positive or positive to negative).
Going into V
‐
Clamp can be instantaneous (< 2 ms) or can be delayed
up to 500 ms.
Returning to I
‐
Clamp mode can be programmed to be:
Manual return.
On external MODE BNC input going low or high, depending on how
the logic is set for going into voltage
‐
clamp mode.
After a programmable time ranging between 2 ms and 500 seconds.
Example of Auto Mode Switching
The following switches from I
‐
Clamp to TEVC mode when membrane
voltage in headstage 1 passes through +20 mV in a negative to positive
direction. It stays in TEVC mode for 500 ms generating a 0 mV to 10 mV
p-p
10 Hz Seal Test waveform and then returns to I
‐
Clamp. The cycle then
repeats.
Set up both I
‐
Clamp and V
‐
Clamp modes using the appropriate tutorials
and model cell prior to going into AUTO mode. This will prevent
oscillations when switching into a new mode.
Make sure to uncheck
Oscillation Detection
in the appropriate V
‐
Clamp tab
when setting up the V
‐
Clamp mode.
To initiate an I
‐
Clamp to V
‐
Clamp transition, a waveform in headstage 1
that moves through +20 mV is required. To do this we will use a TUNE
input from Headstage 2.
1. In Channels 1 & 2 select IC mode.
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