V
m
x10 – Output BNC reporting the transmembrane potential (active only in current
clamp mode).
I
m
– Output BNC reporting membrane current in both voltage and current clamp modes.
Rear panel BNC’s
I
m
/V
m
OUT– Output BNC reporting membrane current when instrument is in voltage
clamp mode, and V
m
x10 when instrument is in current clamp mode.
I
m
/V
m
TELEGRAPH – Provides TTL logic to indicate voltage clamp or current clamp mode.
0=I clamp, 1= V clamp
COMMAND IN – Differential input BNC for voltage command from external sources (e.g.
signal generator or computer). Since the center pin and sleeve are the (+) and (-)
inputs, respectively, the sleeve is not grounded. The applied voltage is attenuated by
the COMMAND SENSITIVITY switch and is available in both voltage and current clamp
modes.
The COMMAND IN input BNC is disengaged when TEST PULSE is active (internal
command), when the COMMAND SENSITIVITY toggle switch is off, or when the amplifier
is in zero current mode (MODE selector switch set to I
o
).
GAIN TELEGRAPH – Output BNC reporting I
m
gain as a combination of the GAIN switch
selection and the gain multiplier (x0.1, x1.0 or x10) dependent on the headstage in
use. Telegraphs range from 0.5 to 7.0 V in 0.5 V steps as shown below.
Gain telegraph settings