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
W H A T C O U L D BE N E W A B O U T A BOTTLE? No one thing, but a combination of advantages makes NALGENE® LABORATORY BOTTLES the greatest idea since glass. For many labs, the mere fact that they're unbreakable is reason enough to standardize on Nalgene bottles. Others choose them for their resistance to acids, caustics, bacterial growth. And their light weight makes a big difference... safer handling and storing. Now you can select from Teflon* FEP, polyethylene, polycarbonate, or polypropylene; sizes from one ounce to thirteen gallons—natural or amber, narrow or wide mouth. Ask your lab supply dealer. Or write for our Catalog L-962. The Nalge Co., Inc., Dept. 1129, Rochester 2, New York.
• 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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