FAX (978)745-3065, www.daedalon.com, e-mail:daedalon@cove.com
DAEDALON CORPORATION
Instruction Manual
For
EC-33 Geiger Computer Interface USB
Hardware
Introduction
This interface is designed to connect to a computer’s USB (Universal Serial Bus)
port, power a Geiger tube, detect pulses, and send count rate information back
to the computer. The interface consists of a high voltage power supply to operate
a Geiger-Müeller tube and a microcontroller to communicate with the host
computer. The GM tube connects to the Interface via the color-coded 4 mm
banana jacks located on the rear panel.
The interface connects to the computer USB port with the supplied 2 m cable.
Since all power for the Interface is derived from the host computer’s USB port,
there is no need for batteries or power cables.
The high voltage Geiger tube power supply has preset outputs at 450 and 900
Volts. A third setting allows the output to be adjusted between 0 and 1200
Volts. An analog to digital converter reads the tube voltage, which is sent back
to the host computer along with count information. This is useful in developing
count rate vs. voltage plots to determine the plateau range for the tube.
The
“STATUS”
of the Interface is indicated by two pilot lights on the panel. The
“STATUS”
will initially light up red to indicate the device is receiving power. Its
color will be yellow when the Interface has been recognized by the computer,
and green while software is collecting data.
The
“COUNT”
LED flashes when a pulse has been detected from the GM tube.
This is particularly helpful in verifying that the device is receiving counts from
the source. Software problems can be separated from hardware problems by
observing this indicator. The Interface also includes an audible transducer
producing a chirp for each event. This feature may be disabled via a rear panel
switch.
The Daedalon EC-33 Geiger Computer Interface has been designed to work with
the Windows operating system, as well as Macintosh computers.
