5
Low frequency switch
•
Use this three-position rotary switch to select the
low-frequency rolloff applied to the Fetrode™
buffer assembly outputs.
•
Choices are
o
0.02 Hz
o
0.15 Hz
o
1.50 Hz
CMR adjust
•
Adjust this multi-turn potentiometer to minimize
common-mode interference (usually 50/60 Hz
power line noise)
.
Output connector (back panel)
•
Connect your recorder or other downstream
device to this BNC receptacle.
Electrode considerations
•
Use only good quality Ag/AgCl electrodes, such as
UFI Model 1081SNP, that include snap fasteners
to which the Fetrode™ buffer assemblies can be
attached.
•
Do not use inferior electrodes, for example those
with stainless steel inserts.
•
Subject’s clothing, especially polyester materials,
will probably generate electrostatic noise if subject
moves. Fetrodes™ may pick up such noise.
6
•
Prevent electrostatic noise by asking your subject
to remove clothing or to wear tight-fitting clothing
that cannot move enough to generate noise.
•
You must use ground (reference) electrode.
Locate it roughly equidistant from active electrode
sites (those equipped with Fetrode™ assemblies).
•
Do not abrade active electrode sites. You may
need to abrade the ground electrode site if you are
recording low- frequency, low-level signals when a
large 50/60 Hz powerline noise source is present.
Using the Model 2283FT(i)
•
Select appropriate electrode sites for desired
measurements.
•
Apply electrodes to subject, then snap two
Fetrode™ buffer assemblies to electrodes.
•
Snap ground reference lead to electrode and plug
other end into green jack on back panel.
•
Connect Model 2283FT(i) output jack to your
recorder or other downstream device.
•
Turn power switch to ON position.
•
Rotate amplification switch until signal to recorder
is maximum size without clipping.
•
Rotate low-frequency switch to roll off (suppress)
undesired low frequencies.
•
If signal is upside down, just unsnap leads to
Fetrodes™ and reverse connections.
•
Adjust CMR control for minimum 50/60Hz
interference.