IN DC HIGH VOLTAGE SUPPLIES stability and performance mark quality. For economy, too... LOOK FOR THIS MARK.
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Some time ago we decided to de velop a line of high performance power supplies t h a t would comple ment our sensitive electrometers and picoammeters. And yet be suitable for general use, too. So we designed, improved and now offer a choice of Keithley voltage supplies t h a t give you better per formance and greater reliability a t lower cost. They're easy-to-use with photomultipliers, electron multipliers, semiconductors and
in other high voltage applications. As a group, they have a lot in common. They're current-rated at 10 ma with less than 1 mv rms noise. Yet, safety-oriented with an output capacitance of less than 0.10 /^fd and current limited to 13 ma. Accuracy is better than 1%. C o n n e c t o r s front a n d r e a r allow fast setup. And every power supply a d a p t s easily to remote control or auto matic programming.
NEW, 0-3100 VDC . . . $450
NEW, 0-2100 VDC . . . $395
SELECT ANY OUTPUT FROM 0-3100 VOLTS with our Model 246. OR 0-2100 VOLTS with our Model 245. Each dials voltages in 10-volt steps and each has a trim potentiometer for further resolution to 50 mv. Stabilities better than 0.01% per 8 hours, line regulation of 0.001% and load regulation of 0.002% assure years of dependable performance.
IMPROVED, 0-1200 VDC . . . $345 O U R 0-1200 V D C M O D E L 240A is a reliable general purpose power source t h a t supplies stable voltages in 1-volt steps. I t ' s rated for 10 ma— smoothly recovers from no-load to full-load in 35 milliseconds. For personal demonstrations and technical literature, call your experienced Keithley Sales Engineer. Or contact Keithley I n s t r u m e n t s , Inc., 28775 Aurora Road, Cleveland, Ohio 44139. In E u r o p e : 14, Ave. Villardin, 1009 Pully, Suisse. Prices slightly higher outside the U.S.A. and Canada.
K E I T H L E Y Circle No. 114 on Readers' Service Card
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See ACS Laboratory Guide for All Products/Sales Office
VOL. 40, NO. 13, NOVEMBER 1908
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