Radiac Set
AN/PDR-56D
IM-160D/PDR-56
Radiacmeter (Alpha Survey Meter)
Measures 0 - 1,000,000 Counts Per Minute
Alpha survey meter using a scintillation type detector.
This unit uses two "D" size 1½ volt batteries.
Tag states it was manufactured for: Navy Department - Ship Systems Command
Manufacturer: Gulf Aerospace Corp. / Serial Number: A110
Government price in 1969, for the PDR-56: $300.00
Nameplate & Control Panel
Left & Right Inside Views
This unit has been de-milled, all wires cut and some tubes missing.
Meter Face Close-Up
The scales on the meter are color coded as follows.
0 - 1,000,000 Counts Per Minute = Red
0 - 100,000 Counts Per Minute = Orange (shown above)
0 - 10,000 Counts Per Minute = Pink
0 - 1,000 Counts Per Minute = Yellow
The battery check scale is white.
DT-224/PDR-56 Radiac Probe
Serial Number: D116
Inside Of Scintillation Probe & Nameplate
Alpha particles enter through the Mylar® polyester film screen, hitting a phosphor scintillation screen and
create small flashes of light. Clear Lucite® "light pipes" direct the light from the screen to the
photomultiplier tube that is housed in the vertical portion of the probe.
The photomultiplier tube has been removed from this probe.
Bottom View Of Probe