Physiological recordings can be easily contaminated by noise and interference. In many cases, high electrode contact impedance is a big part of the problem. Noise often appears as 50 or 60 Hz "hum" from surrounding AC-powered electrical devices or as erratic spikes due to any motion of the lead wires. In virtually every case, these troublesome artifacts can be mitigated or completely eliminated by reducing contact impedance at the skin/electrode interface. UFI's Checktrode™ applied electrode contact impedance testers are designed to help accomplish this task.

UFI offers four time-saving and frustration-saving electrode contact impedance checking instruments. Our standard 1089 allows rapid evaluation of contact impedance when two electrodes are used. For multiple electrode configurations, our 1089ES and 1089NP allow rapid, individual evaluation of large electrode arrays such as EEG caps.

Description
Specifications

The UFI model 1089 MkIII Checktrode supplies quick and easy evaluation of total contact impedance and offset voltage between two applied electrodes. The 1089 uses an AC excitation method which removes the effects of the polarization errors from the impedance reading. Leads with both the older .080" pin plugs as well as the newer .060" safety jacks are supported. The inclusion of a standard male snap allows electrode lead testing as well. A loaded battery test function is also provided. The 1089 is powered by a standard 9V battery, and automatically shuts down after 3-6 minutes.

View the user manual here...

1089 general specifications

impedance readout: 3 1/2 digit LCD display
contact impedance range: 0-199 KOhm (custom ranges available)
excitation frequency: 30 Hz (typical)
typical excitation current: 10 uA p-p (constant current)
calibration setting: 50 KOhm
input connectors: 2 each 0.080" and 0.060" safety jacks and 1 male snap (1089)
battery test load: 1 KOhm
power switch: push-button on with auto-shutdown after 5 minutes
rugged plastic case: 6" x 3.5" x 1.5" (Std 1089)

Model 1089e Economy Checktrode (Impedance)	Model 1089ES Checktrode (impedance meter)
Model 1089NP Checktrode (impedance meter)