Axon MultiClamp 700A User Manual

64 • Reference Section
MultiClamp 700A Theory and Operation, Copyright 2000, 2001 Axon Instruments, Inc.
Figure 4.5. Schematic bridge balance circuit and adjustment procedure.
Bridge Balance in the Bath
Some investigators like to set Bridge Balance in the bath, before attempting to impale
cells. This is to make it easier to see when a cell has been penetrated.
Check the Tuning checkbox and set the parameters to -1 nA and 50 Hz. Observe the
Membrane Potential on Scaled Output. Press the Auto Bridge Balance button; the fast
voltage steps seen at the start and finish of the current step should be eliminated. You
may need to manually adjust the Bridge Balance M value for optimum balance. The
M value is the resistance of the electrode.
Bridge Balance in the Cell
The Bridge Balance should be frequently checked when inside a cell, because the
electrode resistance can drift. While setting Bridge Balance, Pipette Capacitance
Neutralization should also be set. (See Capacitance Neutralization.) Both settings can
be monitored continuously through the experiment by injecting a small current step
near the beginning of each data sweep.

Axon MultiClamp 700A Specifications

General

Brand	Axon
Model	MultiClamp 700A
Category	Amplifier
Language	English