Crusty old Joe's

Kodiak Alaska Military History

The official web site of the Kodiak Military History Museum

SCR-296A Radar

NEW this just in as of 22 March 2011. Dave Ostlund found a manual for this radar. It's available here as a 20+ megabyte PDF file. The original is 6.7 by 4.35 inches or 171 by 110 mm.

SCR-296 Radar antenna unit and equipment building on hillside at Alexai Point, Attu Island. Trough at right of building carries leads to antenna unit. [NARA 342-88-001-1311]

Operating table and equipment of SCR-296 Radar installation at Alexai Point. [NARA 342-88-001-1312]

Zeto Point on Adak Island is the location of this radar installation; powerhouse at left, operations building and tower on right. Complete installation by Alaska Communication System engineers. [NARA 342-88-001-1291]

Interior of SCR-296 Radar operations hut at Ulatka Head, Dutch Harbor. Equipment in main rack, top to bottom: modulation generator, receiver, control panel, transmitter and H.V. rectifier; on table, left to right: test oscilloscope, L.V. rectifier, indicator, azimuth oscilloscope, azimuth control unit, range oscilloscope and range unit. [NARA 342-88-001-1292]

RA-49 regulated rectifier power supply, TM 11-1105, 1505


BC-718 3" Oscilloscope 3AP1/4 & 6 tubes, azimuth display

I-110 azimuth indicator

BC-719 5" Oscilloscope 5HP1 & 19 tubes, range display

BC-723 Range Unit two 6SJ7
side view

MG-16 motor generator

BC-720 modulator

BC-716 receiver

BD-108 power control panel

BC-717 transmitter

RA-50 high voltage rectifier

Two views of an SCR-296 tower and remains of other towers on Attu. Probably at Murder Point. Photos 2001.

SCR-296A*  700 MC Coastal Defense Radar

Consists of
BC-716    Radar Receiver, 700 MC, 14 tubes
BC-717    Xmitter      6 tubes
BC-718*   3" Oscilloscope  3AP1/4 & 6 tubes, azimuth display
BC-719    5" Oscilloscope  5HP1 & 19 tubes, range display
BC-720*   Modulator     8 tubes
BC-723    Range Unit  two 6SJ7
BC-724    Power Drive
BC-725    Calibrator    TM 11-1048  1942
BC-726    Calibrators I-147, 156, 168  3 tubes  TM 11-1128  1943
BC-1286*  AGC Unit    U/W BC-716, RA-49    P/O SCR-296A 1943
BC-1296   Range Control Unit      U/W BC-723 Range Unit, RS-296
BC-1297   Position Xmitter. C/O Potentiometer RS-296, FT-336-A
BD-106    Switchboard or duplex panel
BD-108    power control panel
RC-136    MK 3 IFF Set, 157-187 MC            U/W MPM-4, SCR-296A
BE-82     cabinet
RA-49     regulated rectifier power supply, TM 11-1105, 1505
RA-50     high voltage rectifier
RM-36     control unit
I-110     azimuth indicator
MG-16     motor generator

    The main cabinet for the radar transmitter-receiver is a metal 
rack about six feet in height containing five slide-in drawer units 
on the left and a narrow compartment on the right running from top 
to bottom containing coax stubs tunable with rack and pinion.
    The manufacturer is Western Electric.
    There are a number of aspects of the three nomenclature 
systems, the way they were implemented, and the effects of 
wartime events, that can be very confusing.  First, you will find 
a mixture of two or more nomenclatures in the same system!  There 
was at least one Army radar, SCR-296-A, that included a Navy I.F. 
strip, CAOS-50AEY (see Modification Work Order 11-1505-1).  
Additionally, various AN nomenclatured systems contained either 
Army nomenclature or Navy nomenclature components.  

SCR-296-A Fixed Medium Wave Coast Artillery Fire Control Set


DESCRIPTION: Fixed Coast Artillery gun-laying medium wave radar, assigned to modern 6 inch or larger batteries.
USES: Set is designed to track a surface target in range and azimuth. Data are sent to the plotting room and used in firing. An SCR-296-A normally is assigned to one battery, but may furnish data to more. Works with IFF RC-136-A.
Range is shown on "A" scope. The target is tracked in azimuth with a pip matching oscilloscope or a zero-center meter. Range accuracy is about ± 30 yards while azimuth accuracy is about ± 0.20 degree under the best conditions. The set has a dependable range of 20,000 yards on a destroyer size target when employed at a height of 145 feet. Site should be not less than 100 feet above sea level; 150 to 500 feet is recommended.
TRANSPORTABILITY: Shipment includes areas and separate generator. When crated the total weight is 91,763 lbs. Largest unit is 5,270 lbs.
INSTALLATION: SCR-296-A includes a tower, an operating building, and two power plant buildings. The tower is obtainable in heights of 25, 50, 75, and 100 feet. Concrete floors must be put in locally.
PERSONNEL: Operating crew consists of 5 men in addition to a power plant operator and maintenance man who should be available at all times.
POWER: Primary power of 2.3 KW is supplied by PE-84C -- commercial or auxiliary 110 V, AC single phase. Generator needs high octane gas.


Main index This page updated 2011 March 22.