Radio Navigation Equipment - Signalspaning.se

Marker Beacon Receiving Set AN/ARN-12 is a
lightweight airborne marker beacon receiver utilizing a
superheterodyne type circuit with a crystal controlled oscillator.
It is designed to give aural and visual indications
when flying over any army marker beacon transmitter at
altitudes between 10 and 4,000 feet, and over CAA marker
beacon transmitters at altitudes between 100 and 35,000
feet. Reception is on the standard marker beacon channel
of 75 me. The equipment responds to a 75 mc. signal which
is modulatedby400, 1,300 and 3,000 cycles. The receiving
set is designed for operation from the aircraft 24 volt de.
system.
A filter is required for selection of indication
of 400, 1,300 and 3,000 cycle modulation. This is provided
in a separate unit which may be installed or omitted depending
upon the mission of the aircraft.
This equipment will replace Marker Beacon Receivers
RC-193, RC-39, and RC-43.
Test Equipment required for maintenance includes
Test Set 1-76.
Army Supply Program requirements as of 1 February
1945 were 11,860 sets forthe calendar year 1945,
and 23,599 sets for 1946.
TUBE COMPLEMENT
NO. TYPE NO. TYPE
2 28D7 2 6AL5
5 6AJ5
Radio Receiver R-122/ARN-12
IF tLASSIFI[P
Antenna Assembly AS-215(XA)/ARN installed bottom midfuselage
AT-11 airplane. 1-Interior 2-Exterior
POWER INPUT 72 WATTS @ 24 VOLTS
DC.
FREQUENCY 75 MC
TYPE OF SIGNAL MCW
RANGE ARMY BEACONS 10 TO
400 FEET CAA BEA-
CONS 100 TO 35.000 FT
SENSITIVITY 500 - 1500 MICROVOLT
SELECTIVITY 600 at 700 KC
Antenna Assembly
MARKER BEACON RECEIVING SET AN/ARN-12 TOTAL WEIGHT 25 LBS.
Component
Radio Receiver
Applique Unit
Mounting
Antenna Assembly
and includes cords, plugs, cables, etc.
May 1945
Nomenclature
R-122/ARN-12
MT-28/ARN
AS-215/ARN
Size
6" x 10" x 6"
10" x 2" x 6"
Length 19" x Diam. 12"
AN/ARN-12
Weight
9 Lbs.
7 Lbs.
1 Lb.
5 Lbs.