The HiZ-223 is a very high input impedance, dual channel electrometer designed for measurements with high resistance ion-selective microelectrodes.
1015Ω Input Resistance
Designed for measurements with ion-selective microelectrodes
Probe Test Port
Standby mode protects input amplifiers
Driven Guard Shield reduces stray capacity and noise
The amplifier features two small active headstages, allowing the first stage of amplification to take place at the electrode site. Shunt capacity is reduced and electrical interference, such as electrostatic noise and motion artifact common to this type of recording, are greatly minimized.
To reduce the noise and stray capacity even farther the probe housing includes a signal driven guard. A portion of this inner driven shell is exposed at the probe tip allowing a spring shield to be extended over the electrode holder and microelectrode.
The amplifier features a probe test port that permits testing of the electrode test feature and setting of the probe leakage current, (IG). A standby mode is included and should be used when attaching glass microelectrodes or electrode holders to the probe input. While in the standby mode the voltage at the probe input is clamped near zero volts thus protecting the input.