KEITHLEY INSTRUMENTS

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Stable to 0.01% . . . Indefinitely

NEW KEITH LEY

3500V D.C. SUPPLY The extreme stability of the Model 242 is not specified in hours. N o w over several months—you can perform extended duration measurem e n t s . C u m u l a t i v e d r i f t of t h i s regulated supply is prevented by a self-correcting feedback loop featuring a temperature compensated zener diode reference, photo-chopper c o m p a r a t o r and wire wound sampling resistors. 300 V to 3500V are delivered at 25 ma, with less than 1 mv combined ripple and noise— ideal for photo tube, photo multiplier and electron multiplier applications. Other specifications contributing to the outstanding value of the Keithley 242 are shown below. • o u t p u t : 300 to 3,500 V at 25 ma in 1 volt s t e p s — p l u s , m i n u s , or f l o a t i n g t o 4500 V • stability: 0 . 0 1 % indefinitely, m i n u t e warm-up

after

30

• accuracy: ± 0 . 1 % • r i p p l e a n d noise: Less t h a n 1.0 m i l l i volt r m s • line r e g u l a t i o n : 0.005% for 10% c h a n g e in l i n e v o l t a g e

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• load r e g u l a t i o n : 0.005% from zero to full l o a d • o v e r l o a d p r o t e c t i o n : A u t o m a t i c disc o n n e c t if current e x c e e d s 27 ma • p r i c e : $850

Other Regulated DC Supplies Model 241, 0-1000 V, 0.05% accuracy

$800

M o d e l 240, 0-1000 V, 1.0% accuracy

$345

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