The new SR-255B... the industry's most extraordinary value in a 10" strip chart recorder. C o m p a r e the lengthy list of s t a n d a r d features against other recorders. C o m p a r e the s p e c i f i c a t i o n s . T h e n c o m p a r e the p r i c e . The SR-2S5B clearly offers more recorder for y o u r dollar. Choice of input spans. Other r e c o r d ers in this p r i c e range offer only one span. T h e 255B gives y o u p u s h b u t t o n - s e l e c t i o n of f o u r : 10 mV, 100 mV, 1 V and 10 V full scale. A n d a v a r i a b l e span c a p a b i l i t y is built-in to a l low e x p a n s i o n to 100 V full s c a l e . 10 digitally-derived chart speeds. W e p i o n e e r e d the c o n c e p t of the d i g i t -
ally-driven stepper m o t o r chart d r i v e y e a r s a g o . Most m a n u f a c t u r e r s have a d o p t e d it now. This system uses a p r e c i s i o n stepper motor s y n c h r o n ized to a highly stable internal o s c i l lator or external T T L s i g n a l . T h e r e is no b a c k l a s h . . . no c o m p l i c a t e d m e c h a n i c a l system t o get out of a d j u s t ment. C h a r t s p e e d s of 10, 5. 2 , 1 , 0.5, 0.2, 0 . 1 , 0.05, 0.02 a n d 0.01 inches or c m per m i n u t e are instantly select a b l e . A n d speeds are a c c u r a t e t o 0 . 5 % or better. High impedance floating input p r o v i d e s better than 1 0 ' o h m s input i m p e d a n c e w i t h less than 10 nA bias c u r r e n t o n 10 mV, 100 m V a n d 1 V r a n g e s . T h i s i n p u t i m p e d a n c e is higher t h a n many other r e c o r d e r s a n d minimizes s o u r c e l o a d i n g . I m p e d a n c e o n the 10 V range is 1 megohm. Swftchable input filtering e n h a n c e s t h e r e c o r d e r ' s ability to reject 5 0 / 6 0 Hz noise by 2 0 d B . Complete remote control capability by T T L signals is s t a n d a r d . Other features include easy c o n v e r s i o n t o met ric system, easy p a p e r loading, pushbutton c h a r t a d v a n c e , rackmount design, electrical pen l i f t . . . all s t a n d a r d . Use t h e c o u p o n to get your FREE H e a t h / S c h l u m berger c a t a l o g a n d learn more about real value in s t r i p c h a r t recorders.
Three neui high performance, loui cost lab instruments from Heath/Schlumberger
Factory assembled & calibrated SR-255B, 20 lbs $335.00* Also available is a 1V fixed span recorder for O.E.M. and industrial use. Contact factory for price and delivery information.
Two new autoranging 110 MHz frequency counters I n t r o d u c i n g the new H e a t h / S c h l u m berger SM-128A and SM-128B . . . a pair of h i g h p e r f o r m a n c e counters at very reasonable prices. T h e 128s d e liver g u a r a n t e e d p e r f o r m a n c e to 110 MHz w i t h 15 mV sensitivity. T y p i c a l p e r f o r m a n c e is even better: 140 MHz at 2-10 mV sensitivity. Front panel sensitivity c o n t r o l a l l o w s a d j u s t m e n t of t h e i n p u t a m p l i f i e r t r i g g e r level above and b e l o w the zero-crossing p o i n t . . . ideal for m i n i m i z i n g the ef fects of noise on t h e s i g n a l . T w o preset g a t e intervals of 1 s e c o n d a n d 10 ms are s w i t c h - s e l e c t a b l e . . . or use the a u t o r a n g i n g f u n c t i o n , w h i c h a u t o m a t i c a l l y determines the c o r r e c t range for m a x i m u m resolution w i t h out o v e r r a n g i n g . T h e SM-128A uses a s t a n d a r d c l o c k stable to ± 1 0 p p m over 0-40° C. For a p p l i c a t i o n s re q u i r i n g very high p r e c i s i o n , c h o o s e t h e SM-128B, w i t h t e m p e r a t u r e sta bility of ± 1 p p m . A d d i t i o n a l features of both versions i n c l u d e 7-digit LED readout w i t h leading zero blanking . . . h i g h i m p e d a n c e 1 m e g o h m / 1 5 pf for m i n i m u m loading . . . external t i m e base oscillator input for very high a c c u r a c y measurements or fre q u e n c y ratio w o r k . . . dual-primary power supply . . . rugged, compact d e s i g n . Use the c o u p o n to get your FREE H e a t h / S c h l u m b e r g e r c a t a l o g and see the rest of our f r e q u e n c y counter l i n e . . . f r o m 30 M H z to 600 MHz. Factory assembled & calibrated S Μ Ι 28 A, s t a n d a r d t i m e b a s e , 10 lbs $325.00* Factory assembled & calibrated SIM128B, high stability timebase. 10 lbs $395.00*
SM-128A 110 MHz autoranging frequency counter, only S325"
SR-255B 10", 10 mV-10 V, 10 speed recorder, lust $335"
HEATH
FREE! Latest Heath/Schlumberger electonic instruments catalog, featuring these and dozens of other high performance, low cost instruments: scopes, power supplies, meters, generators, etc. Use coupon to get yours now.
Heath/Schlumberger Instruments ^ ^ Μ 3 Ξ Ι Ί Dept. 531-011 Benton Harbor, Michigan 49022 • Please send latest electronic instruments catalog. ' Name — I Title _ I Company/institution I Street I City—
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I EK-400R I
CIRCLE 88 ON READER SERVICE CARD ANALYTICAL CHEMISTRY, VOL. 45, NO. 13, NOVEMBER 1973 · 1075
