Johnston Laboratories, Inc

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An unprecedented offer from Johnston Laboratories!

The only particle-photon detector you can lease! The MM-1 Electron Multiplier For pulse counting or current measurement of electrons, ions, UV or x-ray photons, and energetic neutral atoms or molecules. Guaranteed reactivateable. Delivered gain: 10 6 to 10 8 . Noise less than 1 count-minute at 10 7 gain. Gain stability at count rates in excess of 10 6 /second. Bakeable at 350° C. No ion feedback. Non-magnetic. 1.5 sq. in. active surface area. SHOULD YOU LEASE OR BUY? If budget limitations force you to buy electron multipliers that must be discarded when they lose gain, you'll be better off leasing the M M - 1 . If you need the superior performance of the MM-1, but for only a limited time, then leasing will be more economical than buying. If you require the dependable performance of the MM-1 in a long term project, you'll do better if you buy it. If you're not sure how long you are going to need the M M - 1 , lease it now and pay only for the time you actually need it. You will always have the option to buy the MM-1 with a large amount of the leasing cost credited toward the purchase price. Write for complete leasing data, specifications, and application notes.

Johnston

Laboratories, Inc.

THESE ELECTRONIC COMPONENTS AVAILABLE FOR YOUR COMPLETE MATCHED SYSTEM. All Solid State High Voltage Power Supply (HV-4R). Ultra low noise for operating electron multipliers, photo multipliers, proportional counters, and ionization chambers. Small, lightweight, 500 to 6,100 volts DC range, reversible polarity, highly filtered noise,less than 300 microvolts. Drift less than . 0 1 % / hour, . 0 2 % / d a y . Preamplifier-amplifier-discriminator (PAD-1). For use with electron multipliers and photo multipliers in mass spectrometers and fast counting systems. Charge sensitive; rise time: 3 nsec, output: 4 volts into 50 ohms. Adjustable discriminator: 20:1 range. Rugged, miniature. MM-2: miniature version of M M - 1 . Also available on lease plan.

3 Industry Lane, Cockeysville, Maryland USA 21030

CIRCLE 91 O N READER SERVICE CARD

48 A • ANALYTICAL CHEMISTRY, VOL. 43, NO. 6, MAY 1971

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