Dagan IX2-700 Manual de instrucciones - Página 8

Navegue en línea o descargue pdf Manual de instrucciones para Amplificador Dagan IX2-700. Dagan IX2-700 14 páginas. Dual intracellular preamplifier

IX2-700 Dual Intracellular Preamplifier

OPERATION

Each of the two independent channels in the IX2-700 can be used as a

bridge Channels 1 and 2 have Bridge Balance and Holding Current

controls.

PROCEDURE

When beginning, ascertain that the system is grounded properly and that the

noise is low. Connect the current and voltage outputs to an oscilloscope. Set the

gain on the oscilloscope to yield 10mV/div. (i.e., 1mV/ div for the 10V output; also

scale Imon by headstage N). Turn the capacity compensation and bridge balance to

the minimum, and the offset voltage and holding current to zero. Make sure that

the step command and the Z test are also off.

ADJUST DC OFFSET

Insert the electrode tip into the bath solution. Adjust the DC offset control so

that the voltage is at ground potential (ground voltage trace, adjust position on

oscilloscope to desired position, uncouple voltage channel, and return trace to the

same position using the DC offset control).

Z TEST

The Z Test can now be used to determine the resistance of the electrode.

Depress the Z test button. There should be a square wave on the oscilloscope

voltage trace of 1mV/megohm of electrode resistance. This measurement is

obtained by passing a 1nA square wave through the pipette. Note that this

resistance test (scale by headstage multiplier N) disables the bridge balance

control. Providing the electrode resistance is within the range you are interested in

working with, you can proceed to balancing the bridge.

BALANCE THE BRIDGE

The bridge must be balanced to effectively "subtract out" the effect of the

potential drop across the microelectrode, allowing you to record only the events at

the cell membrane. The procedure is as follows: