TM11-5895-846-14
(5) On the Gunn Oscillator module mounting
(2) Pull on the two front panel handles to
brackets, loosen the four captive screws which secure
extend the drawer to its open position.
the module brackets to the frame.
(3) Disconnect coaxial cable W4 from A4 Z1
(6) Prior to installing the new Gunn Oscillator,
J1, coaxial cable W3 from A4 Z1 J3, and coaxial cable
it is necessary to transfer the module mounting brackets
from UPCONVERTER to A4 Z1 J2.
from the old module to the new module.
(4) Loosen the four captive screws which
(7) On both sides of the module, note the
secure the module to the chassis and remove the
position of the mounting screws relative to the slotted
module from the chassis by pulling it upward.
holes in the mounting brackets. Remove the mounting
(5) Replace the module by performing steps
brackets and install them on the new replacement
(1) through (4) above in reverse order.
d. Removal and Replacement of YIG Filter Module
module in the same relative position.
(8) Place the module in the small frame,
engage the four captive screws, and secure the module
(1) Turn the POWER switch to the OFF
in place.
position, remove the coaxial cables from the front panel,
(9) Check that the clearance between the
and loosen the eight coaxial screws on the converter
frame front of the module tuning shaft and the retaining
drawer.
nut in the frame front panel knob assembly is
(2) Pull on the two front panel handles and
approximately 1/8 inch.
extend the drawer to its open position.
10. Push in on the front panel tuning knob.
(3) Remove the coaxial cable from the input
Check that the tuning knob shaft blade engages
(J1) and the output (J2) on the YIG filter module.
smoothly with the module tuning shaft in both the
(4) Remove the four screws retaining the
horizontal and vertical orientations.
module to the chassis and remove the YIG filter module.
(11) If the tuning shafts engage properly,
(5) Replace the YIG filter module by repeating
proceed to step (14) below. If the tuning shafts do not
steps (1) through (4) above in reverse order except
engage properly, check if the problem is caused by
replace cables and connectors and tighten screws. Use
improper clearance (proceed to step (12)) below or by
the torque wrench supplied for proper assembly.
e. Removal and Replacement of Frequency
improper shaft orientation (proceed to step (13) below).
(12) Recheck the clearance.
Remove the
module and reposition the mounting brackets. Move the
(1) Turn the POWER switch to the OFF
brackets towards the front of the module to increase the
position, and remove the coaxial cables from the front
clearance or towards the rear to decrease the clearance.
panel, and loosen the eight captive screws on the
Repeat steps (8), (9) and (10) above as necessary.
converter drawer.
(13) Check the horizontal and vertical
(2) Pull on the two front panel handles and
orientations. Remove the module. On the rear of the
extend the drawer to its open position.
synthesizer front panel, loosen the retaining nut and
(3) Loosen the four captive screws which
reposition the tuning knob shaft in the horizontal and/or
secure the Y1 module to the chassis and remove the
vertical planes, as necessary, to obtain proper shaft
module.
engagement. Repeat steps (8), (9) and (10) above as
(4) Replace the module by performing steps
necessary.
(1), (2) and (3) above in reverse order.
(14) Connect P1 to chassis connector XY2 and
f. Removal and Replacement of 1 MHz Step
engage the two captive screws.
(15) Connect coaxial cable W4 and at Y2 J1
NOTE
tightening with the torque wrench provided.
Either or both of these modules may
(16) Close converter drawer and tighten the
be removed by the following
eight captive screws.
procedure.
(17) Replace front panel coaxial cables.
(1) Turn the POWER switch to the OFF
(18) Turn Power switch to ON.
position, remove the coaxial cables on the front panel,
c. Removal and Replacement of Main Loop Module
and loosen the eight captive screws on the converter
drawer.
(1) Turn the POWER switch to the OFF
(2) Pull on the two front panel handles and
position, remove the coaxial cable from the front panel
extend the drawer to its open position.
and loosen the eight captive screws on the converter
(3) Loosen the four captive screws which
drawer.
secure the modules to the chassis and pull upward on
the module to remove it from the drawer.
(4) Replace the module by performing steps
(1) (2) and (3) above in reverse order.
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