ELC-01MX User Manual
version 2.6
page 15
Extracellular recording unit
The extracellular recording unit consist of (20) HP FILTER (Hz) switch and (21) POT.
OUTP. SENSITIVITY switch.
Hint: Set the MODE OF OPERATION switch to OFF for extracellular low-noise
recording.
(19) HP FILTER (Hz) switch
Switch for setting the corner frequency of the high-pass filter (attenuation: -6 dB/octave)
in AC recording mode. DC Recordings are done by switching the HP FILTER (Hz)
switch to DC.
Hint: During AC recording, a DC signal is always provided at the POTENTIAL
OUTPUT x1 BNC connector (#13).
(20) POT. OUTP. SENSITIVITY switch
Switch for scaling the POTENTIAL OUTPUT at the POTENTIAL OUTPUT connector
(#11). Scaling factors: x10, x100, x1000.
Important: The POT. OUTP. SENSITIVITY switch is only related to the POTENTIAL
OUTPUT BNC (#11) and is always active, i.e. not only in extracellular recordings but
also in CC, BRIDGE and VC/VCx10 mode.
(21) R
EL
/ BRIDGE ON switch
Switch for activation of either the electrode resistance test circuit (switch set to: R
EL
) or the
BRIDGE balance circuit (switch set to: BRIDGE ON) in CC mode. Both settings are indicated
by LEDs (#26).
The BRIDGE balance circuit compensates for the electrode artifact and allows accurate,
intracellular measurements of the membrane potential und application of current stimuli. The
BRIDGE is adjusted using the BR.BAL. potentiometer (#23).
(22) BR.BAL. potentiometer
If current is passed through the recording electrode in BRIDGE mode, the potential deflection
caused at the electrode resistance is compensated with this control (ten turn potentiometer,
clockwise, calibrated in M
Ω
, range: 100 M
Ω
, i.e. 100 = 10 M
Ω
).
(23) MODE OF OPERATION switch
5-position rotary switch to set the MODE OF OPERATION. The following modes are
possible:
EXT:
VC or CC are selected remotely by a TTL pulse (+5 V) applied to the MODE
SELECT (TTL) connector (#8). HI (>1 V) selects VC, LO (<0.8 V) selects CC.
CC
Current Clamp mode, allows recording and stimulation in current clamp. The
electrode artifact is not compensated unless the BRIDGE mode is activated and
adjusted (see also #22 and #23).
OFF:
CC Mode with all input signals turned off. Can be used for extra- and intracellular
recordings. R
EL
is functional.
VC
VOLTAGE CLAMP mode, allows recording and stimulation in voltage (patch)
clamp. Series resistance and
τ
-slow are not compensated.
VCx10
High range VC mode (up to
±
12 V), used for stimulation and electroporation
