Single Electrode Microdrive system 

The Thomas Pencil Drive System is a single electrode microdrive with integrated preamplifier. This microelectrode manipulator can drive Thomas microelectrodes with the patented rubber tube mechanism as well as Thomas multitrodes. This device has an integrated 8 channel low-noise preamplifier.  
  
The new Thomas Pencil Drive^TM System (Thomas Pen^TM)  has a lot of advantages in contrast to competitors products:

The tetrode/electrode is compley shielded against noise pickup from the environment;
The patented rubber tube drive does not cause any slick or free motion like cable or hydraulic or thread rod driven microdrive systems;
Adaptation to different electrode travel distances for cortical or deep brain recordings;
Modular system;
Networkable software to control one recording setup with multiple Thomas Pen Drives from different workstations by more than one neuroscientist;
System uses thin microelectrodes with high recording quality (e.g. Thomas electrodes or tetrodes);
Low price;
Small size and weight;
Easy setup and many features more  

Figure 1 shows all components of a Thomas Pencil Drive.  

Fig. 1: Components of the Thomas Pencil Drive (1) = Motor control connection cable, (2) = 8 channel preamplifier, (3) = Preamplifier connection cable, (4) = O-rings for cover fixation, (5) = Cover for electrode chamber, (6) = Recording chamber holder, (7) = Electrode guide tube, (8) = Recording chamber (not part of the delivery)

The Thomas Pencil Drive is a lightweight system that can be mounted directly on an implanted primate recording chamber.

Figure 2 shows a Pencil Drive guide tube introduced in a grid hole of a primate recording chamber. 

Fig. 2: Thomas Pencil Drive mounted on a primate recording chamber. The Pencil Drive guide tube is introduced in a grid hole to guarantee high reproducibility of the recording position.

Although the electrode travel distances is 10mm, larger travel distances are available on request. The dimensions of the Thomas Pencil Drive are shown in figure 3.

Fig. 3: Dimensions of the Thomas Pencil Drive for primate recording applications

Beside using the Thomas Pencil Drive for primate recording application it is also possible to use this drive with small animal stereotaxic instruments for small animal recording applications.

Furthermore we have developed a motorized xyz-manipulator with Pencil Drive holder for slice recording applications (see figure 4).   

Fig. 4: Thomas Pencil Drive with Thomas motorized xyz-manipulator mounted on a slice recording chamber

The Thomas Pencil Drive System is delivered with 8 channel motor control unit, motor control software, integrated 8 channel preamplifier with accumulator power supply and charger, primate chamber holder or small animal stereotaxic system holder. 

Fig. 5: Thomas Pencil Drive networkable motor control software graphical user interface. The Thomas Pencil Drive system is delivered with an 8 channel motor control unit (MCU-2) and a single channel software license for each single Pencil Drive. So it is easy to add another pencil drive to a complete setup just by ordering another pencil with another software license.

Fig. 6: Connection diagram of the Thomas Pencil drive system. This connection diagram shows the required connections for driving the motor of the Thomas Pencil Drive

Fig. 7: Connection diagram of the Thomas Pencil drive system. This connection diagram shows the required connections for signal amplifier connection of the Thomas Pencil Drive

The Thomas Pen^TM  is a very lightweight and flexible drive solution for Thomas microelectrodes and tetrodes. It is a modular microdrive concept. One can mount these drives on a recording chamber like shown in figure 1 or to any other stereotaxic instrument. The Thomas Pen is a precision solution for replacement of any manual electrode drive presently used for neurophysiological recordings.

Please do not hesitate to contact us for a custom-made adaptation of the Thomas Pen^TM  to your special recording setup!

Technical Data
Feature            Standard Specification
Electrode travel    10.000μm
Resolution          1μm
Preamplifier        8 channels
Drive principle     Patented Thomas rubber tube drive

Features

High precision & quality “Made in GERMANY” by Thomas RECORDING
Axial resolution better than 1μm, x-y-Positioning with a grid or xyz manipulator
Patented rubber-tube drive, no hysteresis, slick or free motion due to patented rubber tube drive (avoids drawbacks of cable, direct or hydraulic driven systems)
Flexible electrode travel range by chassis extension
Variable speed range from 0...250μm/s, higher velocity on request
No 50/60Hz noise pickup from the environment
No electrode connection cables free in air!
Custom made solutions for each recording application
Stable long-term recordings with thin microelectrodes for hours