The 3211 High-Voltage Amplifier is a workhorse amplifier for driving capacitive loads such as broadband electro-optic (EO) modulators and piezoelectric transducers. The Model 3211 incorporates high-slew-rate, high-voltage operational-amplifier technology to give you extremely precise linear operation over a wide range of input voltages and frequencies. The ±200-V output will swing our broadband EO modulators (pages 43, 45) through 180° of phase shift with bandwidths of up to 0.6 MHz. The peak-to-peak output noise is less than 100 mV in a 1-MHz bandwidth. The front-panel controls include an easy-to-reach, high-voltage on/off switch and a DC off-set that sets the output level anywhere from - 200 V to +200 V, allowing an EO amplitude modulator to be biased for optimum linearity without additional components. Two inputs allow signals from separate sources to be sum-med and amplified. Two bias outputs of +200 V and - 200 V allow single-polarity operation for piezoelectric transducers and other compo-nents. A monitor output provides 1/30 of the output voltage for display on an oscilloscope.