CD V-711 Remote Sensor Radiation Meter

CD V-711 Model 2 Metering Unit, Nuclear Chicago Corp.
This is the metering unit of the CD V-711 Model 2 set manufactured by Nuclear Chicago Corp.Click photos to see larger.

The CD V-711 Remote Sensor Radiation Meter was issued for use in Emergency Operations Centers. There were 600 of the Model 2 units made and only 200 of the Mk III units made. I only have the CD V-711 Model 2 metering unit. I would like to express a very sincere Thanks to Mike for the donation of this rare piece to the Civil Defense Museum! The CD V-711 Mk III photos at the bottom of this page were sent to me by an Emergency Management Director who has the unit in his EOC.

The complete CD V-711 set consists of the meter unit, cables and a remote sensor. I do not have the cable or detector for this metering unit. The button to the right of the selector switch is a meter light switch. The meter lights for as long as the button is pushed. Meter detection range is up to 1000 Roentgens/Hour. Scale ranges are .1, 1, 10 and 100 Roentgens per hour. The "handle" is for hanging the unit from a wall bracket. (See photo below.) Cable connectors to remote sensor are on top of the metering unit. This unit is fairly large and measures, Width 6.25" x Length 10.25" and Depth 4".

The CD V-711 set was designed for permanent mounting in blast-hardened emergency operations centers. The first requirement an EOC requesting a CD V-711 unit had to meet was...
  1. The EOC area must provide:
    1. An estimated protection factor against fallout radiation in excess of 500.
    2. An estimated blast overpressure resistance of more than 10 psi.

From Radiological Defense Planning and Operations Guide DOD/OCD March 1967)

Inside of CD V-711

The CD V-711 Model 2 takes no less than nine D-cell batteries to power it! The CD V-711 Model 2 was designed to hang on the wall from a bracket (see photo below). The cables to the remote sensor unit would be run through a steel pipe where the remote ion chamber detector (see below) would be mounted 3 feet above ground level.

CD V-711 Model 2 Remote Detector Unit

Thanks to the Arnold Brothers Of Montana for these photos.

The CD V-711 Model 2 remote detector unit is an ionization chamber mounted in a metal cover housing with connections at the bottom. The whole unit is designed to be mounted to a heavy 4 inch flat faced pipe flange on 4 inch pipe which would position the detector three feet above the ground. Cabels were supplied to connect the detector and metering unit. Eric Laskowski has some good photos of a CD V-711 Model detector still mounted at an old EOC on his Michigan Civil Defense Museum site. The photos are on his Ottawa County EOC page at this link

Here's a link to a photo of a CD V-711 in service. Look at the back wall to the left of the photo on this page. There is a CD V-711 Model 2 hanging hooked up on it's wall bracket.

711 with wall bracket CD V-711 Meter with light on

Photo at left is the CD V-711 hanging from it's wall mounting bracket. Thanks again to Mike for providing this photo. CD V-711 Model 2 meter light turned on. I believe this is the only civil defense radiological instrument with a meter light. See the CD V-711 Model 2 Manual Here In PDF Format.. CD V-711 Model 2 Manual

CD V-711 Mk III, Nuclear Chicago Corp.

CD V-711 Mk III Metering Unit
This model of CD V-711 has a 10,000 Roentgen per hour detection range. Scale ranges are .1, 1, 10, 100, 1000. The unit uses two cables from the metering unit to the remote detector outside the shelter.

This CD V-711 MKIII is not part of my collection so Thanks To T.H. for the photos!

The following information is from the FEMA CPG 4-1 Volume 6 Instrument Maintenance and Calibration Manual.

CD V-711 Mark III Remote Sensor Radiation Meter.
Two Hundred CD V-711 Remote Sensor Radiation Meters were produced under an engineer development contract. FEMA has granted all of these instruments to the states.
The contract did not require that instruction and maintenance manuals be furnished and none have been produced. Our Emergency Management Systems Test Facility and the Federal Depot have successfully serviced these instruments with the aid of the schematic circuit diagram in Figure 28-1.

The diagram in "Figure 28-1" referred to is simply a copy of the schematic in the case.

Inside The CD V-711 Mk III and Remote Detector Unit

CD V-711 Mk III Uses 3 D-cell Batteries

Detector Unit Data Plate

Underside Of Detector Showing 2 Connectors

Detector Unit

The above photos show the insde of the CD V-711 MkIII case and the remote mounted detector unit. This remote detector doesn't appear to be nearly as sturdy as the CD V-711 Model 2 detector unit. The base mounting plate appears to be gold zinc plated steel which would probably have started rusting pretty quickly if exposed to the elements for even a short time.

Another Photo Of A CD V-711 MK III and a CD V-711 "Model 3" Both By Nuclear Chicago

I received this (pretty amazing) photo from a Mr. Hicks back in June of 2009. I can't remember his comments about these two CD V-711s but the one on the right in the photo is particularly interesting. Notice the serial number of 3 and that is designated as a "Model 3." Evidently it's one of the first of the Mk IIIs made. I have no idea what ever became of these two CD V-711s. Also notice that the meter is different and has CD V-711 on the meter face. The other CD V-711 Mk IIIs I have seen photos of all have the meter type as seen on the CD V-711 in the left of the photo. I don't know if Mr. Hicks had the ion chambers or the wires reels with these CD V-711s or not.