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AT33 Portable Single-Channel EMGstoeltingAT33-pi.jpg (44652 bytes)

With its ON-BOARD MICROPROCESSOR, the AT33 combines ease-of-use with powerful data collection capabilities.

What Can the AT33 EMG Do?

  • Calculate and display summary statistics.
  • Time period integration (TPI).
  • Extremely high signal resolution.
  • Autoranging display from 0.01 to 999 ÁV


The AT33 EMG's instrument controls are at your fingertips. Simply press the desired button to change a setting, record or display session data, or select a feedback option.

Statistical Capabilities

All AT series instruments have BUILT-IN statistical analysis capabilities. Simply press the AT33 EMG's Statistics button when you're ready to begin collecting data. Press it again at the end of the session to display the session mean, max., min. and SD.

Exclusive TPI The unique time period integration (TPI) feature lets you select whether the numeric display provides feedback in real-time -- or updates only once, every 1, 2, 4, 10 or 60 seconds with the mean EMG for that time interval.

Using TPI makes TRAINING PROGRESS CLEARER and documentable (through the manual recording of data).

stoeltingat33-box.jpg (9226 bytes)
Portable. Both battery and line-powered. Complete with all accessories, including a carrying  case.

Superior Feedback

Audio: Long recognized for quality audio feedback, the AT33 EMG audio selections include integrated clicks, a continuous tone and a melodic piano scale. Audio feedback that quickly and CLEARLY CONVEYS CHANGES in EMG activity.

Visual:The AT33 EMG features two visual feedback selections:

  1. an LED numerical display, and
  2. an LED lightbar (engineered to simulate analog meter feedback).

Sensitive & Accurate

The AT33 EMG has AMAZING SENSITIVITY. It is capable of accurately displaying EMG changes of 0.04 microvolts or greater.


The AT33 EMG is designed to meet/exceed the electrical and safety standards specified by UL 2601, IEC 601 and CSA 871. The default parameters are bolded.


Visual Feedback
Display Options Numerical LED + Lightbar, Lightbar only, Numerical LED only, A/B Ratio
Numerical LED Displays Three red digits, 0.5" high
Numerical LED Range 0.01 - 999 microvolts, auto-ranging
TPI (Time Period Integration) Settings 0.5, 1.0, 2.0, 4.0, 6.0, 10.0, 60.0 seconds
Lightbar Three color, 15 segments (7 green, 1 yellow, 7 red)
Lightbar Scale Factor Logarithmic scale corresponding to threshold setting
Audio Feedback
Tones Piano, Continuous, Integrated clicks
Volume Levels 0 to 7, 4 is the default
Audio Provided Continuously, Above or Below Threshold
Statistics Acquired Min., Max., Mean, SD
Sampling Capacity 64,000 data points per session
Resolution 0.04 microvolts
Sampling Capacity 64,000 data points per session
Bandpass 32-220 Hz (3 dB)
Common Mode Rejection 140 dB
Differential Input Impedance 2400 megohms
Input Noise 0.3 microvolts
Sampling Rate 8 Hz (every 0.125 seconds) of VRMS
Leakage Current In compliance with UL 2601 specifications
Audio Output 3.5 mm stereo earphone jack, (mono output)
Analog Output Linear 0-3 volt DC signal, compatible with most computer interfaces
Line Power Input 120 volt, 60 HZ, 220 volt, 50/60 Hz
Battery Longevity Rating 10 to 12 hours continuous use
Battery Recharge 16 hours maximum with built-in overcharge protection
Dimensions & Weight 2.5"H x 7.7"W x 5.3"D; 1 pound 5 ounces


Qty Item
(1) UL listed isolation adapter
(4) Installed Ni-Cad rechargeable batteries
(1) 6-foot EMG sensor cable
(1) Leather strap for ambulatory use
(50) Quick-Stick pre-gelled, disposable EMG electrode sets
(1) Carrying case
(1) Owners manual
Warranty: 1 year parts and labor on instrument; 90 days on accessories, 3 year extended warranty available.

Indications: EMG feedback is indicated where general relaxation training is desired.

Contraindications: There are no known contraindications with the AT33 EMG for the purpose of general relaxation training.

NOTE: No warranty or claim is made regarding the efficacy of products in clinical use, but only with regard to electronic specifications,
which specifications are subject to change without notice.

Prices and specifications subject to change without notice.

AT33 Portable Single-Channel EMG
$829 (if you are in a country requiring  220 volt add $20.)

shipping in the US  $25. Outside the US, contact us with your full address information so we can give you an exact shipping price. 

Other Products: AT53 Portable Dual-Channel EMG

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