6A
ANALYTICAL
CHEMISTRY
Jrl. Ad ND46(16)
Range switch for input circuit having values of 0.02, 0.06, 02 and 0.6 microampere.
Manually operated zero ad juster for continuous zero sup pression of "dark current", independent of range.
Battery Condition Indicator
Manually operated battery rheostat for adjusting range to match light source.
Chart Record is ghost structure on grating scanning 2536.5 A of Mercury 198.
Photomultiplier Tube Output
with this Speedomax Recorder • Here is a recorder t h a t connects directly t o Photo multiplier T u b e s measuring low levels of light as found in ultra-violet a n d visible radiation, R a m a n spectros copy scintillation counting and light scattering studies. As a result, t h e usual separate pre-amplifier is completely eliminated. T h e recorder has a highgain, low-level detector-amplifier t h a t provides direct measurement of currents a s small a s 0.2 χ 10" 8 ampere full scale.
of the chart. I t is not even necessary t o stop t h e Recorder. Other features of this Speedomax Recorder include: a range of sensitivity from 0 t o 0.02 microampere, a 4, 3 o r 2 second balancing speed (full scale) and a chart speed of 120 inches per hour. T h i s instrument is t h e member of t h e Speedomax family designed specifically for u s e with Photomultiplier Tubes. F o r further information, please contact o u r nearest district office or write us a t 4906 S t e n t o n Ave., Philadelphia 44, Pa.
How it operates T h e instrument has four working ranges, 0.02, 0.06, 0.2 a n d 0.6 microampere full scale, to record a wide range of light levels. T o change the range, t h e operator merely t u r n s a manually-operated switch and t h e record continues within the span
LEEDS instruments
NORTHRUP automatic controls ·
furnaces
