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Home :: Radio Set SCR-506

Radio Set SCR-506

12) Required Parts
Items necessary for the installation of Radio Set SCR-506-( ) in Truck, 1/4-ton, 4 x 4,are listed below:

Quantity Stock No. Item
1 2A275-27 Antenna A-27, phantom.
1 2ZI203-422 Bracket FT-422, brush
1 2ZIS74 Cabinet CH-74-( ).
1 2Z2651-421 Clamp MC-421, for Mast section MS-49 and MS-50.
1 2Z2651-422 Clamp MC-422, for securing Mast Sections MS-50 and MS-51.
1 2Z2651-423 Clamp MC-423, for securing Mast sections MS-51 and MS-52.
1 2Z2651-424 Clamp MC-424, for securing Mast Sections MS-52 and MS-53.
2 6Z3147 Connector No. 61007 and Bond-nut BL-50 (Appleton).
2 3E1307A-5.5 Cord CD-307-A, 65", for Headset HS-30-( ).
1 3E1314 Cord CD-314, for Loudspeaker.
1 3E1318 Cord CD-318-( ), for Microphone T-45.
2 3E1604 Cord CD-604, 6", for connecting    Headset HS-30-( ) to Cord CD-307-A.
1 2Z3367 Cover BG-67-( ) for Mast Base MP-57 or MP-37.
1 3H1640 Dynamotor DM-40-( ), 12-volt, with attached spare parts, for Radio Receiver BC-652-( ).
1 3H1642 Dynamotor DM-42-( ), 12-volt, with attached spare parts, for Radio Receiver BC-653-( ).
1 6L50-506V26 Hardware bag.
2 2B830 Headset.
3 3G586 Insulator IN-M86, for tying down mast sections.
3 3G604 Insulator IN-104.
3 3G621 Insulator IN-121.
1 3Z3445 Key J-45.
1 2Z6303.1 Loudspeaker LS-3.
1 2A2090-50 Mast Bracket MP-50.
1 2A2088-57 Mast Base MP-67 or MP-37 (2A2087).
1 2A2349 Mast Section MS-49.
1 2A2350 Mast Section MS-50.
1 2A2351 Mast Section MS-51.
1 2A2352 Mast Section MS-52.
1 2A2353 Mast Section MS-53.
1 2B1617 Microphone T-17-( ).
1 2B1645 Microphone T-45.
1 2Z6721-253 Mounting FT-253-( ), including two Cord CO-280, fuses, and hardware.
1 2Z6721-28.5 Mounting FT-285-( ).
1 2C4452 Radio Receiver BC-652-( ), including crystals, tubes, and spare parts.
1 2C6530-653 Radio Transmitter BC-653-( ), including spare parts and tubes installed.
2 2Z7060-429 Reinforcing plate FT-429, for MP-150.
1 2Z8056 Roll BG-56-( ), for mast section.
50 ft 8Z7926 Rope RP-5, for tying down mast sections.
2   Strap item 50 figure 24.
10 ft 1B146 W-146, for antenna leadins.


Figure 7: Mast base MP-37, assembly for installation


Figure 8: Mast base MP-57, assembly for installation


Figure 23: Mounting FT-285-( ), assembly and details

13. Assembly and lnstollation
a.) Preliminary Check.

Radio Set SCR-506-( ) may be installed in Truck, 1/4-ton, 4 x 4, with either of thefollowing 12-volt conversion kits. Check to see that the conversion has been made beforebeginning installation.

(1) Under-the-hood conversion kit in which all 6-volt electricalcomponents of the vehicle are replaced by 12-volt components.
Two 6-volt storage batteries, one originally furnished with the truck, and one suppliedwith the conversion kit, are installed between the front seats to furnish, in series,12-volt power supply for both the radio set and the vehicular system.

(2) Power-take-off conversion kit in which a 12-volt generator andregulator is mounted over the transmission of the vehicle to be driven. by a belt andpulley operated off the shaft of the transmission. Two 6-volt storage batteries aresupplied with the conversion kit and are installed one behind each front seat. These twobatteries, un series, furnish 12-volt power for operation of the set independently of the6-volt system of the vehicle.

b.) Procedure.
Components of the radio set should be installed as shown in figure 24 and as directedbelow.

Part and Location

Method and Materials

Mounting FT-285-( ) and Loudspeaker LS-3, on floor of vehicle, rear. Remove the rear seat from the vehicle. Figure 23 shows assembly and details of the mounting. Refer to figure 24 for drilling details and drill the floor, rear and left wall of the vehicle. Drill Loudspeaker LS-3 and Mounting FT-285-( ) as shown in figure 24. Install Mounting FT-285-( ) and secure in position with the provided hardware. Reinforce the mounting with the strap (item 50) as shown in figure 24. Fasten the loudspeaker to the mounting with the hardware provided.
Cabe=inet CH-74-( ), on Mounting FT-285-( ). Drill Cabinet CH-74-( ) for installation of the insulators as shown in detail in figure 24. Place the cabinet on the mounting and secure with the hardware provided.
Mounting FT-253-( ) in Cabine CH-74-( ). Fasten to the floor of the cabinet with the hardware provided. Route the two Power Cords CO-280 to the vehicle terminal box, and secure with clamps as. shown in figure 24. Use the connectors and bondnuts to bush the power cord at the knockout hole of the terminal box.
Mast Bracket MP-50, Bracket FT-422, and Reinforcing Plate FT-429, on the left side of the vehicle, at rear. Mount the brackets and reinforcing plates and secure with the hardware provided.
Mast Base MP-57 or MP-37 on Mast Bracket MP-50. Refer to figure 7 or 8 and assemble the mast base as follows: Place item 1 over the hole in the mast bracket. Place item 2 over item 1. Place item 3 over item 2. Insert item 4 through the hole in the mast bracket. Place item 5 over the flange of item 6. Insert item 6 upward through the hole in the mast bracket. Place items 7 and 8 beneath item 6 and fasten entire assembly in place with items 9 and 10.
Mast Sections MS-49 to MS-53 and Clamps MC-421 to MC-424, on.Mast Base MP-57 or MP-37. Screw the mast sections together and secure with the clamps. Fasten the clamps to the male end of the mast sections. Then screw the mast antenna into the mast base. When not in use, carry the mast sections in Roll BG-56-( ).
Cover BG-67-( ). Place over the mast base when the mast sections are not in use.
Insulators IN-104 and IN-121, on Cabinet~CH-74-( ) and left side of the vehicle. Install with the hardware provided as shown in figure 24.
Radio Transmitter BC-653-( ), and
Dynamotor DM-42-( ), on Mounting FT-253-( ).
Mount the dynamotor in the dynamotor compartment of the transmitter and secure with the five screws provided. Connections are made automatically by the plug on the rear of the dynamotor chassis which engages the socket in the rear of the compartment. Remove the patch cover on the top of the transmitter, right end, and place the six links in the 12-volt position as indicated by the arrow on the link strap. Secure the transmitter to the right end of Mounting FT-253-( ) with the thumbscrew locking devices.
Radio Receiver BC-652-( ), and Dynamotor DM-40-( ), on Mounting FT-253-( ). Remove the screws on the outer edge of the from panel of the receiver and the screw in the rear center of the cabinet and remove the receiver chassis from the cabinet. Install the dynamotor on the top of the receiver chassis and lock in place with the snap side fasteners. All connections to the dynamotor are made by the cord terminating in Plug P-250, when placed in the socket on the receiver chassis. The name plate on the front panel of the receiver should be turned to read 12-volt operation. Secure the receiver to the mounting with the thumbscrew locking devices.
Wire W-146. Cut Wire W-146 to required length and solder-tin ends. Connect to the terminal on the mast base, pass through Insulators IN-121 and IN-104, and connect to the antenna terminal of the radio transmitter.


Figure 24: Installation of Radio Set SCR-506-( ) in Truck, 1/4-ton, 4x4

c.) Cording and wiring.
Cord and at wire Radio Set SCR-506-( ) as shown in figure 24. Connect andsecure so as not to interfere with the  accessibility and operation of the equipment.Enough slack must be left to permit free movement of all units having shock mounting.Cording or cable likely to rub against sharp edges should he taped with at least twolayers to prevent damage. Solder-tin all wire ends.

(2) To prevent accidental shorts of the battery, do not connect thepositive 12-volt and negative 12-volt leads (in the terminal box) until all otherconnections have been completed.

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