Alignment of Tuning Capacitor C2

the ground lead to the RT-505/PRC chas-

rotation curve by turning C1 counterclockwise (from

shaft end) and noting that the 520 indicates a de-

sis.

crease in capacity. Reset to 68 microfarads (uuf).

d. Connect the other lead of the 520 to

f. Tighten clamp on the Cl tuning shaft.

the stator section of tuning capacitor C2

g. Adjust the RT-505/PRC-25 tuning

at A3, pin 6 (fig. 31).

knobs to 52.95. The 520 should indicate

e. Set the 520 on the X10 uuf scale,

10 uuf, or a difference of 58 uuf from the

loosen the clamp on the C1 tuning shaft,

30.00 mc indication (e above).

and adjust the s h a f t of the tuning ca-

h. If a difference of approximately 58

pacitor C2 for an indication of 6.8 on the

uuf is not obtained, repeat the procedure

520.

given in b through g above.

Note: Check to see that this adjustment has been

i. Replace module A8 in the chassis.

made on the proper side of the capacity-per-degree

rotation curve by turning C2 clockwise (from shaft

end) and noting that the 520 indicates a decrease

51. Alignment of Tuning Capacitor C2

in capacity; reset to 68 uuf.

(fig. 39)

f. Tighten the clamp on the C2 tuning

Align tuning capacitor C2 as outlined

shaft.

below. Do not change the control settings

g. Adjust the tuning knobs to 52.95 mc.

unless specifically directed.

The 520 should indicate a difference of

a. Remove module A3 from the chassis.

approximately 58 uuf.

h. If a difference of approximately 58

b. Adjust the tuning knobs for 30.00 mc

and set the BAND switch at 30-52.

uuf is not obtained, repeat the procedure

c. Use a Ballantine Direct Capacity

given in b through g above.

i. Replace module A3 in the chassis.

Meter Model 520 or equivalent. Connect

Section III. FOURTH ECHELON TESTING PROCEDURES

umns; then perform each specific test

52. General

procedure and verify it against its per-

a. The testing procedures are prepared

formance standard.

for use by Signal Field Maintenance Shops

and Signal Service organizations respon-

53. Test Equipment, Tools, Materials, and

sible for fourth echelon maintenance of

Additional Equipment Required

signal equipment to determine the accept-

a. General. All test equipment, tools,

ability of repaired signal equipment. These

materials, and other equipment required

procedures set forth specific require-

to perform the testing procedures given

ments that a repaired Receiver -Trans -

in this section are listed in the following

mitter, Radio RT-505/PRC-25 must meet

charts and are authorized under TA 11-

before it is returned to the using organ-

17, Signal Field Maintenance Shops, and

ization. The testing procedures may also

TA 11-100(11-17), Allowances of Signal

be used as a guide for the testing of

Corps Expendable Supplies for Signal

equipment at third echelon if the proper

Field Maintenance Shop, Continental United

tools and test equipments are available.

States.

A summary of the performance standards

b. Special Requirements.

is given in paragraph 67.

(1) Specific models of test equipment

b. Comply with the instructions preced-

were used to perform the test pro-

ing each chart before proceeding to the

cedures given in paragraphs 56

chart. Perform each test in sequence.

through 66. If these test procedures

Do not vary the sequence. For each step,

are performed using other models

perform all the actions required in the

Test equipment control settings a n d

of the test equipments, it may be

Equipment under test control settings col-

necessary to allow for test con-