PASCO SN-7927A Geiger-Müller Counter - Manual

Equipment
The Geiger-Müller Counter is equipped with a built-in
Geiger-Müller (G-M) tube and integral power supply.
Its power indicator, an LED, lights when an operating
voltage is supplied to the unit. The unit has a buzzer that
emits an audible signal for each pulse that is recorded. A
plastic cap that provides protection for the delicate mica
membrane is included. The cap has a venting hole that
prevents the creation of a vacuum or pressure when the
cap is removed or replaced.
➤ Caution: The mica window is extremely del-
icate. Do not cover the hole in the protective cap
when removing or replacing it, and leave the cap
in place except when alpha radiation is being
measured. Never touch the mica window!
Instruction Sheet
for the PASCO
Model SN-7927A
Geiger-Müller Counter
012-07905 B
© 2001 PASCO scientific
Introduction
The PASCO SN-7927A Geiger-Müller Counter senses
beta, gamma, and alpha radiation when connected to a
computer interface such as the ScienceWorkshop

500 or
750 Interface. The built-in power supply allows direct
connection of the Geiger-Müller Counter to the input ter-
minal of any computer interface that provides an avail-
able operating voltage of +5 V, 20 mA.
Use the Geiger-Müller Counter in all experiments de-
scribed in the SE-7997 LabNet Geiger-Müller Interface
manual and experiment guide, as well the SN-7973
Nuclear Science experiment manual. Its performance is
nearly identical to that of the SE-7970A Geiger-Müller
Probe, with several advantages:
•
direct connection to the Science Workshop 500 or 750
Interface (no additional power supply or adapter
needed)
•
versatile positioning options (hand-held or adjustable
on a rod stand) that allow the device to be held closer
to the radiation source
•
audible feedback: the device beeps when it registers a
count
Required equipment:
- computer interface that provides an available operat-
ing voltage of +5 V, 20 mA, such as the Science
Workshop 500 or 750 Interface.
Additional equipment suggested:
- Small Base and Support Rod (SE-9451)
- Radioactive Sources (SN-8110)
Data:
Window material: Mica
Diameter: 9.14 mm
Density: 1.5-2 mg/cm2
Count rate: max. 11,111 per sec (from a min. dead-time
of 90 microseconds).