Pasport SN-7927A Instruction Sheet

®

Geiger-Müller Counter

Protective

Plastic Cap

Power

Indicator

(LED)

SN-7927A

Instruction Sheet

012-07905C

Introduction

The SN-7927A Geiger-Müller Counter is a sensor with a
Tip-Ring-Sleeve type plug that can be connected to a PASCO
Interface. The Geiger-Müller Counter can sense alpha, beta,
and gamma radiation when used with PASCO Data Collection
Software. (NOTE: If your Interface has only PASPORT input
ports, use a Digital Adapter (PS-2159) to connect the sensor to
the interface.) Features include the following:

• Versatile positioning options, either hand-held or
mounted on a rod stand.

• Audible feedback (the device beeps when it registers a
count).

Equipment Included

Item Number

Geiger-Müller Counter SN-7927A

Required

Item*

PASCO Interface

PASCO Data Collection Software

(*See the PASCO web site at www.pasco.com for information
about PASCO Interfaces and Data Collection Software.)

Recommended

Item* Number

Radioactive Sources (set of 3) SN-8110

Sensor Mounting Rod ME-8965

(*See the PASCO web site at www.pasco.com for information
about radioactive sources, rods and bases, and clamps.)

Equipment

The Geiger-Müller Counter is equipped with a built-in Gei­ger-Müller tube and integral power supply. The light emitting
diode (LED) Power Indicator lights when an operating voltage
is supplied to the sensor. The unit has a buzzer that emits an
audible signal for each pulse that is recorded. The sensor
includes a plastic cap that provides protection for the delicate
mica membrane. (The cap has a small venting hole to prevent
the creation of a vacuum or high pressure when the cap is
removed or replaced.)

®

Geiger-Müller Counter

Sensor

Plug

Sensor

DIGITAL

Port

Digital Adapter

PASPORT Interface

CAUTION

The mica window is extremely delicate. DO NOT cover the
small venting hole of the plastic cap when you are removing
or replacing the cap. Leave the cap in place except when alpha
radiation is measured. Never touch the mica window!

Setup

1. Connect the sensor plug to a DIGITAL input port on the
PASCO Interface.

2. Connect the interface to a computer and turn on the inter­face.

• Eating, drinking, and the application of cosmetics in the
laboratory are not permitted.

• Pipetting by mouth is never permitted. (Use pipette fill­ers.)

• Wear gloves and lab coats when working with all liquid
radioisotopes.

• Wash your hands thoroughly before leaving the lab.

• Pour radioactive liquid waste into an approved liquid
waste container - NEVER into a sink.

• Report all spills, wounds, or other emergencies to the
instructor.

• Maintain good housekeeping at all times.

• Store radioactive materials only in the designated storage
area, and do not remove sources from the lab.

Specifications

3. Start the Data Collection Software. Setup a display.

For information on selecting and configuring the sensor, refer
to the Online Help System and User’s Guide for the data col­lection software.

• NOTE: Use a Digital Adapter (PS-2159) to connect the
sensor to a PASCO interface that does not have a DIGI­TAL input port. See the illustration.

• Connect the sensor to port 1 on the Digital Adapter.

• Connect the Digital Adapter to a PASPORT input port on
the interface.

NOTE: The Geiger-Müller counter displays the number of
counts in a given period of time. To change the period of time,
adjust the sampling rate.

Nuclear Safety

Most of the radioactive sources available to educators are very
low level isotopes referred to as “license free” sources. How­ever, observe the following guidelines:

Window material: Mica

Window diameter: 9.14 millimeters (mm)

Window density: 1.52 milligrams per square centimeter

Count rate (max.): 11,111 per sec (for a minimum dead time of

90 microseconds)

Technical Support

Before calling PASCO Technical Support, please have the appa­ratus, this user's guide, and the following information available:

• Product name, model number, and serial number.

• Approximate age of the apparatus.

• Detailed description of the problem or sequence of events
required to duplicate the problem.

For assistance with any PASCO product, contact PASCO at:

Address: PASCO scientific

10101 Foothills Blvd.
Roseville, CA 95747-7100

Phone: [phone] (worldwide)

877-373-0300 (U.S.)

Web: www.pasco.com

Email: [e-mail]

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