Replacement of Radio Frequency Sandpass Filter 1FL3, Radio Frequency Low Pass Filter 1FL4, Elbow Adapter 1CP4, or Directional Coupler 1DC1

TM 11-5820-695-35

(6) Pull the radio test set meter panel away

(10) Solder switch wires to rotary switch

from the radio test set enclosure until it is clear of the

1A16S5 terminals.

shaft on variable attenuator 1AI6AT1, then lower the

(11) Using a -pair of needle nose pliers to hold

meter panel assembly.

crystal mixer lA16Z1 mounting bracket, place the radio

(7) Remove the two self-locking nuts and

test set meter panel on the radio test set enclosure.

washers from the meter terminals.

(12) Replace and tighten the two screws

(8) Tag and remove the wire lugs connected

securing crystal mixer 1A16Z1 mounting bracket.

to the meter terminals.

(13) Replace and tighten the three screws

(9) Remove and save the three locknuts,

securing variable Attenuator 1A16AT,1.

washers, and screws securing meter 1AI16M2 to the

(14) Replace and tighten the eight screws

radio test set meter panel, then lift and remove meter

securing the radio test set meter panel to the radio test

1A16M2.

set enclosure.

(10) Tag and unsolder all wires connected to

(15) Replace the selector knobs on variable

rotary switch 1A16S5.

attenuator 1A16AT1 and rotary switch 1A16S5 and

(11) Remove hex-nut and washer that secures

tighten the two set screws on each knob.

switch 1A16S5 and remove the switch.

(16) Connect cable 1A15W26 to 1A16AT1J2.

(12) 'Disconnect coaxial cable 1A16W24 from

(17) Perform the T-1054(P)/GRC-144(V) and T-

crystal mixer 1A16ZIJ2 and cable 1A15W26 from

1054(P)A/GRC-144(V) radio test set calibration

1A16AT1J2.

procedure (para 341).

(13) Pull variable attenuator 1A16AT1 and

3-36.

Replacement of Radio Frequency Sandpass

crystal mixer 1A16Z1 forward out of radio test set

Filter 1FL3, Radio Frequency Low Pass Filter

enclosure as a unit.

1FL4, Elbow Adapter 1CP4, or Directional

(14) Disconnect mating type N connectors as

Coupler 1DC1 (fig. 3-2, 3-13 and 3-15)

required, to separate variable attenuator A1l6AT1 and

crystal mixer 1A16Z1 from each other.

Removal and replacement procedures for any of the

following; radio frequency bandpass filter 1FL3, radio

b. Replacement.

frequency low pass filter 1F4IA, elbow adapter 1CP4 or

directional coupler 1DC1 require assembly and

(1) Assemble variable attenuator 1A16AT1 and

disassembly of the remaining components.

The

crystal mixer 1A,11i6Zl together by reconnecting the

following procedures detail the steps necessary to

mating type N connectors and mount them in the radio

remove all three components as a single item which can

test set enclosure by pushing the type N connector on

be further disassembled when removed from T-

rear of variable attenuator 1A1AT1 through the rubber

1054(P)/GRC-144(V) or T-1054(P)A/GRC-I 44(V).

grommet at the back of the radio test set enclosure.

(2) Rotate knob shafts on variable attenuator

(1) Remove power from T-1054(P)/GRC-144

1A16AT1 and rotary switch 1A16S5 completely

6() or T-1054(P)A/GRC.-144(V) (para 3-20ag.

clockwise.

(2) Remove plate assembly 1A16 (para

(3) Connect coaxial cable 1A16W24 to crystal

332a).

mixer 1A16Z1 (4) Mount meter 1A16M2 to the radio test

(3) Disconnect the following coaxial cables

set meter panel.

from components mounted on plate assembly lA16:

(5) Replace and tighten the three screws and

1A9W9 from radio frequency bandpass filter 1FL3

locknuts (and lockwashers) securing meter 1A16M2 (6)

connector J1, 1A16W24 from directional coupler 1DC1

Remove the two self-locking nuts and washers from the

connector RF INCIDENT Jo, 1A16W22 from directional

meter terminals, then remove the shorting bar from

coupler 1DO1l connector INGIDE'NT J4, and 1A16W26

across the meter terminals.

from directional coupler 1DCl connector REFLECTED

(7) Connect the wire lugs to meter terminals and

J6.

secure them with the two self-locking nuts and washers.

(4) Remove the four screws and washers

(8) Mount rotary switch 1A16S5 on meter panel

securing radio frequency bandpass filter 1FL3 to plate

assembly removed in a(11) above.

assembly 1A16.

(9) Replace and tighten the hex nut and washer

('5) Disconnect radio frequency bandpass filter 1FL3

securing rotary switch 1A16S5.

from radio frequency low pass filter 1FL4 by rotating the

knurled connector on 1FIA in a clockwise direction.

Remove 1FL3 from plate assembly 1A16.

Change 6

3-54