Powered up & TESTED with 6.3 VAC 60 Hz & +/- 300 VDC power supplies,  Vin = 5 Volts peak to peak, Ri = 10K, Rf = 200K, Vout = 100 V peak to peak clean & steady. 

Datasheet: http://www.philbrickarchive.org/k2-w_operational_amplifier.htm

43+ minute power it up & run it (K2-W): https://www.youtube.com/watch?v=mEFdADrU9MA