Multichannel Systems HiClamp Manual - Manual (Page 29)

TEVC Recording Protocol
23
5.3.2 Tuning the Amplifier
The build in digital amplifier can perform an automatic capacitance compensation in real-time
during the voltage-clamp recordings. This is an unique feature which is necessary to maintain
stable clamping during the movements of the oocyte basket. This automatic capacitance
compensation can be switched on and off with the "Auto On" check box.
Please note that "Auto On" should be checked during all recordings. Otherwise amplifier
oscillations could disturb your recordings or even damage the oocyte.
In order to get the highest stability the function of the automatic capacitance compensation
can be "tuned" although the default values should work under most circumstances.
For tuning switch off the "Auto On" first. You will notice that the displayed value in the
CX_CAP window will change immediately. The exact value depends now on many factors
like the amplifier, position of the TMC etc.
For tuning, change the Cx_Offs value until the CX_CAP window shows a value close
to 400. Now you can reactivate the "Auto On" again and your amplifier is tuned.
Please note that you right now performed tuning of the TMC. Repeat this tuning during your first
recording with a real oocyte, which is placed in the basket. The basket should be in the washing
station, impaled with electrodes, but clamp switched off. You do not have to repeat this tuning
for every oocyte or recording.