RADIOBEACON TRANSMITTER
ND500II (125 WATTS) DOUBLE SIDEBAND - NO VOICE
Page 3-4
15 September 2003
Table 3-1 Power Transformer A1T1 - Secondary Winding Tap Selection
115 VOLT VERSION
230 VOLT VERSION
AC VOLTAGE
CONNECT
CONNECT
AC VOLTAGE
CONNECT
CONNECT
(RMS)
A1U1-1 TO
A1U1-2 TO
(RMS)
A1U1-1 TO
A1U1-2 TO
93-103
A1T1-5
A1T1-11
185-206
A1T1-5
A1T1-11
104-113
A1T1-6
A1T1-10
207-227
A1T1-6
A1T1-10
114-125
A1T1-7
A1T1-9
228-250
A1T1-7
A1T1-9
(b)
Visually inspect all electrical parts and
interconnecting wiring for obvious damage,
loose connections and freedom from dirt, oil or
other foreign objects, paying particular
attention for unwanted conductive materials.
3.8.3
POWER TRANSFORMER A1T1 TAP
SELECTION
(Refer to figure MD-4 to locate
power supply assembly A1 and to figure MD-6 for
its assembly detail): Connect or verify the primary
and secondary winding taps of power transformer
A1T1 are properly connected for the mean RMS
voltage of the AC power source (determined in
paragraph 3.6.5) as follows:
3.8.3.1
Primary Winding Taps
: Connect or
verify the dual primary winding taps of power
transformer A1T1 are connected in parallel when the
AC power source is 115 volts AC or in series when
the AC power source is 230 volts AC, as follows:
NOTE
Wire #1, from A1J1-1, is always connected to
A1T1-4 and wire #2, from A1J1-2, is always
connected to A1T1-1.
(a)
When the mean RMS voltage of the AC power
source is between 90 and 125 volts AC,
connect the dual primary windings in parallel as
depicted in figure SD-2. Connect or verify
A1T1-1 is connected to A1T1-3 and A1T1-2 is
connected to A1T1-4.
(b)
When the mean RMS voltage of the AC power
source is between 185 and 250 volts AC,
connect the dual primary windings in series as
depicted in figure SD-2. Connect or verify
A1T1-2 is connected to A1T1-3.
3.8.3.2
Secondary Winding Taps
: Connect or
verify white wires from terminals 1 and 2 of full-
wave rectifier A1U1 are connected to the appropriate
secondary winding taps of power transformer A1T1,
as follows:
(a)
Using the mean RMS voltage level determined
in paragraph 3.6.5, refer to table 3-1 and
determine the secondary winding tap of power
transformer A1T1 to be used.
(b)
Connect the white wires from terminals 1 and 2
of full-wave rectifier A1U1 to the secondary
winding taps, of power transformer A1T1,
identified in step (a).
3.8.4
RF SYNTHESIZER PWB PRE-
INSTALLATION
: Complete the pre-installation
procedures on RF synthesizer PWB A9 by
completing the
Preparation for Use
section of the RF
synthesizer PWB service instruction manual.
