CD V Stuff Main
CD V-777 Kit
CD V-777A Kit
CD V-777-1 Kit
CD V-777-2 Kit
CD V-777-4 Kit
High School Kit
CD V-750 and Dosimeters
Sold Radiation Meters
Back to Civil Defense Museum
CD V-457 Radiological Demonstrator Unit
"Sister Mary Helene ven Horst, science instructor at Marycrest College
in Davenport, Iowa, teaches students the theory of radiation and the use
of radiological monitoring instruments. A 10-hour course in radiological
meter reading is taught to students at the college, and a 32-hour course
in radiation physics and monitoring is taught at the adult level. Marycrest
College is operated by the Sisters of the Humility of Mary."
This picture is from a US government archives web site. I can't remember
which one. It shows a early version of a CD V-457 set in use. Note the case
on the table behind the women, the old Jordan 457 (see photo below) counter
on the table and the calibrated mounting board on the table in front of
the Jordan 457 counter. The CD V-700s are all early Model 3s.
The CD V-457 demonstrator set-up consists of the calibrated mounting board,
absorbers, radioactive source (C-cell battery shows where the source goes
in the photo) and the GM probe from the CD V-457 counter attached to the
bracket at the end of the board. Aluminum square absorbers are shown in
the photo. The set I have is missing the lead and cardboard square absorbers
and all of the cylindrical absorbers. The cylindrical absorbers were for
placing around the GM tube. The demonstration would have the different types
of absorbers placed in between the GM tube and radioactive source to show
how the different materials blocked or didn't block the radiation from the
This is as close as I can get to duplicating a demonstration with the CD
V-457. I used my trusty turn and bank aircraft instrument with the radium
painted face in place of the original source. The left photo shows a 300cpm
reading with no absorbers in place and the right photo shows a slightly
lower 260cpm reading with 14 aluminum absorbers in place. The aluminum absorbers
don't do much to block the gamma coming off of the face of the indicator.
Here's a photo of a Jordan Model 457 and a later Nucleonic Corp. of America
CD V-457 Model 2. The Jordan unit doesn't have a "CD V" number
on it. This Jordan unit appears to be the same type of 457 in the photo
at the top of this page. I wondered for the longest time what model of 457
was in the photo at the top of this page until I found this one. It's obvious
that the counter in the photo is different than the light blue case CD V-457s.
The Jordan 457 appears to be the same unit in the photo.
Here are a couple of CD V-457s. The one on the left is a Model 3A and the
one on the right is a Model 2. The Model 2, 3 and 3A are all identical on
the front. This counter is a table-top model that operates from a 115 volt
wall plug. It uses the same probe and Geiger-Muller (G-M) detector tube
that the CD V-700 uses.
Here is the CD V-457 case showing the open top tray that holds the manuals
and dosimeters. The red tube on the bottom of the lid has an extra G-M tube
for the counter. Right above the spare tube bracket in the lid is a holder
for 2 radioactive radium beta-gamma sources. The radioactive sources weren't
with this set.
Here is the case with the top tray latched into the lid. The CD V-457 counter
stores in the space to the left. Just in front of it is storage for the
CD V-787 Food and Water Standards. Storage brackets for film reels are in
the center. The dosimeter chargers on the right are sitting on top of a
removable tray that holds the calibrated mounting board. Below that tray
is storage for the square sheild and tube demonstration absorbers.