
BC-535 Preliminary, Rev. 060126
11
Im output
The I
m
OUTPUT
signal present on the instrument front panel is mirrored on this rear panel BNC.
Use of this output rather than the front panel BNC can unclutter your work environment.
External Command In
External
COMMAND IN
signals can be input via BNC connectors on either the instrument front
panel or the instrument rear panel. Input location is selectable by the front/rear
COMMAND INPUT
toggle switch located in the
HOLD
control block on the instrument front panel. Use of the rear input
can unclutter your work environment.
Capacitance Output
The calculated membrane capacitance is output on this BNC when the instrument is in
CAP TEST
mode. Switching the
METER
selector switch to
CAP TEST
activates the
CAP TEST
circuit. This feature is
useful for recording the calculated membrane capacitance into a chart recorder or data acquisition
system. Capacitance output values are 1 mV/pF.
Cap Sync Out
This signal is used to synchronize an oscilloscope or other device with the
BC-535
when using the
CAP TEST
function. The
SYNC OUT
signal is keyed to the peak of the triangular wave for
CAP TEST
which
corresponds to the leading edge of the resulting square wave. The
SYNC OUT
signal is a standard TTL
square wave and is 100
µ
s in duration.
External speaker
A standard ¼” RCA jack is provided for attachment to an external speaker for use in
environments where the ambient noise exceeds the volume capabilities of the internal speaker.
ADDITIONAL INFORMATION
Headstage connections
The
HEADSTAGE
is housed in a small aluminum enclosure and connects to the amplifier via a 1.8
meter cable. Electrode connections are made to two 1 mm mini-jacks marked
INPUT
and
REF
(reference). A third mini-jack (
GND
; circuit ground) is located on the side of the headstage for
connecting to shields or grounding equipment.
The ground connection on the headstage merits specific discussion. The headstage case is
internally connected to the command potential (
INPUT
electrode) of the headstage. As a result, the
headstage does not require a separate ground. However, the isolated grounding jack on the headstage
is provided as a means to ground a small Faraday cage through the headstage if the user desires.
Notes
:
1.
If the Faraday cage is grounded through the headstage (not recommended), then do not run
a separate ground connection from the Faraday cage to any other ground point.
2.
Do not connect the ground on the headstage to either the input or ref electrode as this will
disable the amplifier.
Warner
Instruments
A Harvard Apparatus Company .