TM 11-6625-2948-14&P
MAINTENANCE
This chapter contains maintenance and service instruction
i n s p e c t i o n o f the signal generator. A regular schedule
including recommended test equipment, preventive mainte-
should be adhered to so that minor faults can be
nance, minimum performance tests, troubleshooting and
caught and corrected before more serious damage occurs.
assembly and disassembly procedures.
The
minimum
performance
tests,
detailed
in
The test equipment required for the maintenance of Signal
paragraphs a. through k . will determine whether the
Generator AN/URM-206 is listed in Table 4-1.
s i g n a l g e n e r a t o r i s operating within the specifications listed
in Table 1-2.
PREVENTIVE MAINTENANCE
a. Electrical Power Input, Switch Selection and Turn-On
Perform a preliminary visual and manual inspection of the
Procedure. The signal generator is shipped ready for
operat i o n , w i t h t h e 1 1 5 / 2 3 0 V s w i t c h e s o f S G -
signal generator before undertaking any maintenance
1145/ UR M an d MD-1075/URM for 115 vac. When the
procedure. Remove the top and bottom dust covers of
signal generator is operated from a 230 V supply set
the signal generator to inspect its interior. Look for loose
the 115/230 V switches to 230 V and replac e th e
or damaged parts, dust, dirt, oil or grease, and corrosion.
fuse in the SG-1145/URM with the 1.5 amp fuse and
the fuse in MD-1075/URM with the 1 / 8 a m p f u s e .
Correct such conditions before proceeding with
The FREQ S ET 50/60, 4 00 Hz switch is set to
m a i n t e nance.
50/60 Hz. When the line frequency is 400 Hz, set
the FREQ SET 50/60, 400 Hz switch to 400 Hz.
Connect p o w e r c a b l e B 1 60 8 2 6 t o t h e A C O U T P U T
W ARNING
connector of MD-1075/URM and AC INPUT
connector of SG-1145/ URM. Connect power
THE STABILIZER INPUT TERMINAL
cable 6160833 to the AC INPUT connector of MD-
BOARD, ON THE REAR PANEL, HAS A
1075/URM and the external ac power source. Set
REGULATED POTENTIAL OF 1850
the POWER switches on SG-1145/URM and MD-
1075/URM to their ON positions. Allow a 20-minute
VOLTS DC ON ITS TERMINALS. SEVERE
warm-up period before attempting any of the
SHOCK OR DEATH MAY RESULT FROM
m i n i m u m performance tests. At the end of each test,
ACCIDENTAL CONTACT WITH THESE
disconnect the equipment.
TERMINALS. THE TERMINALS ARE
COVERED TO PREVENT ACCIDENTAL
b. Output Frequency Range and Accuracy Test.
CONTACT. THE COVER SHOULD NOT
BE REMOVED UNLESS AN EXTERNAL
Set the FREQUENCY GHz control to 7.00 GHz.
(1)
LOCK BOX IS TO BE CONNECTED.
Set MODULATION SELECTOR switch to CW.
(2)
C AU TION
(3) Set ∆F control to central "0" position.
DO NOT DISTURB ANY ADJUSTMENTS
(4) Adjust POWER SET control for CAL on the
ON COMPONENTS OF THE KLYSTRON
p o w e r monitor meter.
CASTING.
A
COMPLETE
REALIGNMENT MAY BE REQUIRED IF
(5) Set ATTENUATOR control to read 0 dBm
o u t p u t o n the attenuator dial.
ANY ADJUSTMENTS ARE TOUCHED.
Change 2 4-1
