WIll CORPORATION - Analytical Chemistry (ACS Publications)

WIll CORPORATION. Anal. Chem. , 1952, 24 (1), pp 26A–26A. DOI: 10.1021/ac60061a726. Publication Date: January 1952. ACS Legacy Archive. Cite this:An...
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26 A

ANALYTICAL

Laboratory

INSTRUMENTATION

Equipment

NEWS

OF THE MONTH

PORTABLE ^ ^

I

pH METERS

*T

DESK TYPE METALLOGRAPH ( A O M o d e l 2 4 0 0 ) The last w o r d In ease, looks, accuracy! AH controls o p e r a t e f r o m sitting posi­ tion. Features Include automatic focusing, instantly c h a n g e a b l e magnification, easy g r a i n - s i l e meas­ urement, built-in p h o t o g r a p h i c eyepieces. Will's 1 7 7 9 I T . Request Bulletin M I 6 V - 9 5 0 . Beckman p o p u l a r M o d e l N-2 meter is fwlly port­ a b l e , r u g g e d l y built f o r outdoor w o r k . Hinged cover contains accessories. 1 6 1 8 3 T $ 195

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Beckman M o d e l N - I pH Meter (not shown) has single case with attached carrying handle. 1 6 1 82T $180 Send f o r complete

BECKMAN PYREX CELLS low-PRICED cells o f " P y r e x " Brand glass, f o r M o d e l s DU a n d Β Beckman Spectrophotometers. For work in the 3 2 0 to lOOOmu r a n g e . W i t h Pyrex cover. 2 4 3 5 6 T $6

VACUUM OVEN For small labs. O v e n o"diam-, 8/3"deep. Range from room temp. to 125°C. Thermostat control to ± 0 . 2 5 ° C . For 115 V / A C . 20871 $105

literature.

FLEXIBLE BOTTLES New 1 and 2 gallon sizes. T o u g h , i n e r t , almost unbreakable; much safer f o r trans­ porting a n d storing liquids. Supplied with plastic screw caps. 3789T 1-gal., e a . $ 1 2 ; 2 - g a l . ea. $ 1 8 6 Smaller sizes—1 oz. to 3 2 oz. Ask f o r prices.

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'MULTI-RAY' LAMP

MUFFLE FURNACE

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(Temco M o d e l RCE) O n e of six sires a v a i l ­ a b l e . O p e r a t e s at a n y temperature from 3 5 0 ° to 1850°F. Solid aluminum, with remov­ a b l e heating chamber 4 3 / 4 " w i d e , 4 ' Λ " high, 6"deep.For]15V/AC. 14801 $85

It's F a s t e r . . . Easier to order from WILL

Your inquiry gets instant, cour­ teous attention — a n d is han­ d l e d under personal supervision o f an individual withyears o f e x ­ perience in l a b o r a t o r y supply. FIVE b i g warehouses, all linked b y t e l e t y p e , give y o u fast, f l e x i b l e service to meet unusual needs.

Four Interchangeable tubes p r o v i d e short­ w a v e UV f o r disinfec­ tion, l o n g w a v e UV f o r fluorescence, north sky­ light f o r color match­ ing, a n d a white light of strong intensity. 115 V, 0 0 - c y / A C . 17401 $32

For more data on any of these items— PHONE-WRITE-WIRE-TELETYPE your nearest WILL office-warehouse: WIll

CHEMISTRY

CORPORATION

Rochester 3, Ν . Y.

W I l l CORPORATION

Mew York 12, Ν. Υ.

W I l l CORPORATION of Md., Baltimore 1, M d . SOUTHERN SCIENTIFIC CO., INC.. Atlanta 1, G a . BUFFALO APPARATUS CORP.. Buffalo 5, Ν. Υ

control heavy duty equipment. The classical example has been thermostatic controls, in which the vacuum tube as­ sembly provided an essentially "no cur­ rent" regulation of sensibly heavy heat­ ing currents. Industrial practice has required Icftig-term and trouble-free service, and in this sense, vacuum tube regulators, although vastly superior to the older mechanical arrangements, have shown residual deflects primarily due to a variable and unpredictable cathode and heater life. Another defect was the limited degree to which these relays could be adapted to a wide range of signal input resistance. The new development is the cold cathode pilot relay made by the Haledy Electronics Co. This relay uses the Type TT-1 cold cathode triode which has no heater and has a cathode of practically unlimited life. No trans­ former is required and the circuitry is correspondingly simplified. The relay will operate over any input resistance from a dead short to 10 megohms and with leads from the control device of almost any desired length. The input control current has a maximum value of 2 microamperes. The output of the cold cathode triode directly operates a S.P.D.T. relay having a contact capac­ ity of 5 Α., at 115 volts a.c. Under these conditions, the maximum gain of the system could be rated at 2,500,000. For circumstances under which heavier power must be controlled, a Haledy mer­ cury contactor is available which has a rating of 30 amperes, at 115 volts a.c, or 20 amperes at 220 volts a.c. An additional advantage of the cold cathode relay is its instantaneous ac­ tion, because no preliminary warm-up or stabilization period is required. The normal output of the cold cathode triode in this control device is 15 ma. through a load of 2500 ohms. The specifications for the standard model SS cold cathode electronic pilot relay are summarized as follows: input resistivity range, 0 ohm to 10 meg­ ohms; maximum input current, 2 micro­ amperes; maximum input lead length, unlimited ; power requirements, 2 watts, 115 volts, 60 cycles, one side grounded; relay, S.P.S.T. contacts rated at 5 am­ peres at 115 volts 60-cycle; electronic tube; one TT-1 cold cathode triode; case, 18-gage drawn steel, wrinkle gray (Continued ore page £8 A )