500 WATT RADIOBEACON TRANSMITTER
ND2000A-02x-xx0
Page 5-4
15 January 2005
(l) Set
TEST-Volts/Current
switch to
+15V - SIDE A
(
B
).
(m) Verify multimeter is connected between meter
M2 (+) and ground.
(n) Multimeter's indication shall be between 14.7
and 15.3 V dc.
(o)
TEST-Volts/Current
meter's indication shall be
within 10% of the reading in step (n).
(p) Record difference between reading obtained in
step (n) and reading obtained in step (o) as
TEST-Volts/Current
meter's correction factor for
+
15 VOLTS
in
Established References
section of
table 5-2.
(q) Set
TEST-Volts/Current
switch to
-15V - SIDE A
(
B
).
(r) Connect multimeter between meter M2 (-) and
ground.
(s) Multimeter's indication shall be between -14.25
and -15.75 V dc.
(t)
TEST-Volts/Current
meter's indication shall be
within 10% of the reading in step (s).
(u) Record difference between reading obtained in
step (t) and reading obtained in step (s) as
TEST-
Volts/Current
meter's correction factor for
-15
VOLTS
in
Established References
section of
table 5-2.
(v) Connect multimeter between test point
A10TP13 and ground.
(w) Multimeter's indication shall be between 14.5
and 15.5 V dc.
(x) Connect a multimeter between test point
A7A1TP2 (A8A1TP2) and ground.
(y) Multimeter's indication shall be between 14.5
and 15.5 V dc.
(z) Connect a multimeter between test point
A10TP7 and ground.
(aa) Multimeter's indication shall be between -14.25
and -15.75 V dc.
5.3.5
CARRIER FREQUENCY CHECK:
Check the carrier (RF drive) frequency as follows:
5.3.5.1 RF Synthesizer Check:
If the RF drive is
provided by RF synthesizer PWBs (A4A3 and
A5A3), check the RF drive frequency and level, as
follows:
(a) Verify switches are set as tabulated for
Test
Setting
in table 4-1.
(b) Disconnect connector A4P2 (A5P2) from its
mating connector A4A4J1 (A5A4J1).
(c) Set
RF
switch to
ON
.
RF
DRIVE ALARM
lamp
A4DS2 (A5DS2) shall turn on.
(d) Connect a frequency counter between test point
A4A3TP7 (A5A3TP7) and ground.
(e) Frequency counter indication should be within
0.0005% of assigned RF carrier frequency. If
necessary, set switches S1 through S5 on the RF
synthesizer PWB.
(f) Connect an oscilloscope between test point
A4A3TP7 (A5A3TP7) and ground.
(g) Oscilloscope waveform indication shall be
similar to the waveform depicted in figure 6-4,
with a peak-to-peak voltage between 12.1 and
14.9 volts.
(h) Set
RF
switch to
OFF
.
(i) Connect connector A4P2 (A5P2) to its mating
connector A4A4J1 (A5A4J1).
5.3.5.2
RF Oscillator Check:
If the RF drive is
provided by fixed frequency, RF oscillator PWBs (A4
and A5), check the RF drive frequency and level, as
follows:
(a) Verify switches are set as tabulated for
Test
Setting
in table 4-1.
(b) Verify the appropriate oscillator crystal, for the
assigned carrier frequency, is installed in crystal
holder A4A3XY1 (A5A3XY1).
