Bridge Amplifier

The BA-1S (npi electronic) is a wide-bandwidth high impedance amplifier designed for intracellular current clamp recordings with sharp microelectrodes, as well as perforated or tight seal patch configurations. Currently, BA-1S amplifiers are used in vertebrate (rat, mouse, cat, fish etc.) and invertebrate (leech, crab, snail, insect etc.) neurons, muscle cells, other excitable tissue and plant cells.

For more information on the BA-1S amplifier please visit npi electronic website

Bridge Amplifier

The BA-1S (npi electronic) is a wide-bandwidth high impedance amplifier designed for intracellular current clamp recordings with sharp microelectrodes, as well as perforated or tight seal patch configurations. Currently, BA-1S amplifiers are used in vertebrate (rat, mouse, cat, fish etc.) and invertebrate (leech, crab, snail, insect etc.) neurons, muscle cells, other excitable tissue and plant cells. The BA-1S is housed in a 19" rackmount cabinet and equipped with functions like two ranges for bridge balance, an oscillation shut-off circuit for protecting the preparation and three potential monitor ranges. The amplifier comes with a small headstage with BNC connectors, that can be attached directly to a micromanipulator.

This bridge amplifier is also available as module for the EPMS-07 system.

Features include digital monitors for potential, current, and electrode resistance, a digitally controlled step input unit and powerful cell penetration (BUZZ) functions. An improved capacity compensation unit allows accurate recordings with high resistance microelectrodes.

The BA-1S is housed in a 19" rackmount cabinet and equipped with additional functions like two ranges for bridge balance, an oscillation shut-off circuit for protecting preparation and three potential monitor ranges. Both amplifiers are equipped with small headstages with BNC connectors, which can be attached directly to a micromanipulator. The BA series are also available with a discontinuous current injection mode (switched mode current clamp, BA1-1S-SW system) which eliminates problems associated with the nonlinear properties of microelectrodes.

• Digital Monitors
  For potential, current and electrode resistance.
• BUZZ function
  for easy cell penetration.
• Versatility
  Use with Sharp Microelectrodes and Suction Pipettes.
  The BA-1S allows all kinds of intracellular current clamp investigations - from recordings with sharp electrodes to experiments with suction pipettes.
• Accuracy
  Improved Capacity Compensation An improved capacity compensation unit allows accurate recordings with high resistance microelectrodes.
• Oscillation Shut-off Unit
  Protects the Preparation.

Selection and Options:
All systems include headstage and operation manual.

• BA-1S: Bridge amplifier housed in a 19" rackmount cabinet with separate displays for potential and current
• BA-1S-SW: Bridge amplifier housed in a 19" rackmount cabinet with separate displays for potential and current, and with an additional discontinuous current injection mode
• BRAMP-01R: Bridge amplifier housed in a cassette for the EPMS modular system

Important Publications
Lalley P. M., Moschovakis A. K., Windhorst U., Electrical Activity of Individual Neurons in Situ: Extra- and Intracellular Recording; in Windhorst U., Johansson H. (Eds.) Modern Techniques in Neuroscience Research, Springer Verlag, Berlin, Heidelberg, New York, 1999.

HEADSTAGE:
Input voltage range: ±1000 mV;
Operating voltage: ±15 V;
Size (approx.): 40 x 70 x 20 mm, mounting plate 50 x 70 mm;
Electrode connector: BNC connector with driven shield, grounded enclosure;
Ground connector: 1 mm connector;
Driven shield output: 1 mm connector;
Input resistance: >10E+13 Ohms (internally trimmable);
Current range: ±15 nA into 100 MOhms.

ELECTRODE PARAMETER CONTROLS:
BIAS: range ±150 pA, leakage current adjustable with ten-turn control.
OFFSET: ten-turn control, range ±200 mV.
CAPACITY COMPENSATION: range 0-30 pF, ten-turn control.

CELL PENETRATION:
Application of max. DC currents (-Imax or +Imax), overcompensation of capacity compensation (BUZZ), timer controlled with linear control, assessable with remote switch.

OSCILLATION SHUT-OFF:
Turns off current injection and capacity compensation, function indicated by red / green LED,
disabled / off / reset switch, threshold set with linear control (0-1200 mV).

BRIDGE BALANCE:
adjustable with ten-turn control, 0-100 MOhms and 0-1000 MOhms with toggle switch.

ELECTRODE RESISTANCE test:
10 mV / MOhm obtained by application of square current pulses ±1 nA, display XXXX MOhms.

BANDWIDTH and SPEED of RESPONSE:
Full power bandwidth (Re = 0): >30 kHz, rise time (10 % - 90 %) <10 µs (Re = 100 MOhms), <5 µs (Re = 5 MOhms).

OUTPUTS:
Impedance: 250 Ohms;
Current: sensitivity 1 nA / V, display XX.XX nA, resolution 10 pA;
Potential: BNC connector, sensitivity x10 mV x20 mV and x50 mV, selectable with toggle switch, display XXXX mV.

CURRENT INPUTS:
0.1 nA / V, 1 nA / V, inputs equipped with on / off toggle switch, gating input with digital control of current step size and a resolution of 10 pA, polarity selectable with toggle switch, holding current range ±10 nA with ten-turn control.

POWER REQUIREMENTS:
115 / 230 V AC, 30 W

DIMENSIONS:
19" rackmount cabinet, 19" (483 mm) wide, 10" (255 mm) deep, 3.5" (88 mm) high

All downloads are in pdf format. Use Acrobat Reader to view. If you do not have the latest Reader, download it from the Adobe webpage for free

To save a pdf file to your local machine, right mouse click on link and choose "Save Target As...". You then choose the destination folder you want to save the pdf file to.

The BA-1S amplifier is delivered with a standard headstage, connectors for electrode connection and ground, a power cord and a user manual.

Optional Accessories (ordered at additional cost):

• BA-PRS: Remote switch for penetration unit
• BA-MOD: Passive cell model
• BA-MODA: Active cell model
• BA-EH: Microelectrode holder  
  Includes one holder without port for sharp microelectrodes, one holder with one port for patch electrodes and a holding bar