PHOTOVOLT CORPORATION

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NEW RECORDING DENSITOMETER for

THIN LAYER

CHROMATOGRAMS

Direct, Manual or Fully Automatic Scanning of Plates by Visible or U. V. Absorbance, and by Fluorescence. REPRODUCIBLE • ACCURATE • CONVENIENT

PHOTOVOLT • CORPORATION ^ ^ • 1115 BROADWAY · NEW YORK 10, Ν.Ύ.

Circle No. 204 on Readers' Service Card

PHOTOVOLT Electronic pH METERS

A complete line of pH meters, incorporating permanently frictionless taut-suspension indicating meters, modern electronic tubes and circuits. Simple in operation and maintenance; featuring sealed amplifier plug-in units.

High Precision pH Meter Model 110 <

Two-way pH Meter Model 85 • Single range 0-14, scale length 3", readable to 0.05 pH Unit. • Available —compact battery pack for field use ($38.00 addtl.). • Fully stabilized, simple, usable with all types of electrodes. Write for Bulletin #195

• Single range 0-14, scale length 7", readable to 0.02 pH unit. • Temperature control 0-100° C, voltage selector for 80-260 volts. • Available — carrying cover and baseboard for bottles, beakers. Write for Bulletin #105

*135

$265 Standard Laboratory pH Meter Model 115

Portable pH Meter Model 125

• Single range 0-14, scale length 4", readable to 0.05 pH unit. • Temperature control 20-100° C, available with carrying case. • Additional millivolt scale for redox measurements and titrations. Write for Bulletin #225

• Single range 0-14, scale length 5V2", readable to 0.03 pH unit. • Only 3 batteries, standard radio type, 2,000 hours of service. • Available — carrying frame for instrument, beakers, bottles. Write for Bulletin #118

*225

*175

P H O T O V O L T Tester Model 25 for Checking and Adjusting pH Meters A compact, inexpensive instrument without batteries; for checking performance of PH0T0V0LT and other pH meters. Requires neither electrodes nor buffers. Write for Bulletin #138 $78

C O R P O R A T I O N 1115 B r o a d w a y , N e w Y o r k Ι Ο , Ν . Υ.

Circle No. 205 on Reefers' Service Card VOL. 35, NO. 1 1 , OCTOBER 1963

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