VA-10X User Manual
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version 7.0
page 5
3. VA-10X Components
The following items are shipped with the VA-10X system:
VA-10X amplifier
Headstage
GND connector for headstage (1 mm)
COMMAND connector for headstage (1 mm)
REF connector for headstage (1 mm)
Mains cord
Ground bridge
User manual
Optional accessories:
Electrode holder
Carbon-fiber electrodes,
5µm
3-electrode headstage with differential input
4. VA-10X System
4.1.
System Description
The VA-10X is a sensitive (picoampere range) current amplifier that is intended for
voltammetric measurements with carbon-fiber microelectrodes in biological systems, where
the total currents do not exceed a ten to twenty of nA. It can be used for either DC
amperometry using the built-in voltage source, or it can be operated with user-supplied
external voltage waveforms (e.g. for cyclic voltammetry).
The VA-10X is ideally suited for measurements from single cells plated onto glass cover slips
and with carbon-fiber disk electrodes having diameters of 10 µM or less. However, it can also
be used for measurements made on superficially located cells in tissue slices. The VA-10X is
not recommended for use in
in vivo
recordings with carbon-fiber electrodes having long
cylindrical measuring surfaces, because in this case currents approach the µA range and a
third electrode is required to compensate for the IR drop as currents flow through the
extracellular fluid.
4.2.
Description of the Front Panel
In the following description of the front panel elements each element has a number that is
related to that in Figure 1. The number is followed by the name (in uppercase letters) written
on the front panel and the type of the element (in lowercase letters). Then, a short description
of the element is given. Some elements are grouped in functional units (e.g. OUTPUT unit)
and are described as units regardless of the order of numbers.
