PH220

Although the PH220 pH Probe Amplifier has been retired, some replacement parts remain available (see Ordering Info). The PH220 was a high-impedance differential amplifier used with pH and other ion-specific electrodes (e.g., NH₄, CO₂, NO₃, K, Cl, Ca, SO₄, and Na). It typically was used in laboratory settings where inexpensive, unamplified ion-specific probes could be connected in succession.