500 WATT RADIOBEACON TRANSMITTER
ND2000A-02X-xx0
Page
3-4
15 January 2005
13 as the SWR alarm output. When the reflected
power is excessive and causing the carrier level to be
cutback (reduced), the transistor will be forward
biased and a current sink-to-ground will be applied to
TB3-13 as the SWR alarm output.
3.4.4.4 Battery
Alarm:
The emitter/collector
impedance of a switching transistor to ground is
applied to TB3-14 as the 'remote battery alarm' output.
When ac power is being used as the transmitter's
power source, the transistor will be reverse biased and
apply an open collector to TB3-14 as the 'remote
battery alarm' output. When the AC power fails or is
turned off and an external dc power source (battery) is
the transmitter's power source, the transistor will be
forward biased and a current sink-to-ground will be
applied to TB3-14 as the 'remote battery alarm' output.
NOTE
Current flow through a current sink (switching
transistor) must not exceed 200 mA. Zener diodes are
connected between the output and ground to ensure
voltage transients, induced in the external wiring, are
not coupled to the transmitter's logic circuits. The
external alarm monitoring circuits must operate from
a positive dc voltage power source. An external dc
power supply may be used or +15 V dc from TB4-12
may be used as the voltage source. If the +15 V dc
from TB4-12 is used, it must be remembered that this
voltage is turned off if the transmitter is shut down.
UNPACKING:
3.5
The transmitter is packed in wooden crates
for shipment. A packing list(s) provides a detailed
listing of crate contents.
Crates should be inspected for transit damage prior
to shipment acceptance and/or uncrating.
3.5.1
TRANSMITTER CABINET CRATE:
The transmitter is packed partially disassembled in a
wooden crate that is approximately 178 cm (70
inches) x 74 cm (29 inches) x 76 cm (30 inches).
Shipping weight is approximately 150 kilograms (330
pounds). Open crate and remove the transmitter
cabinet as follows:
(a) Locate crate in an upright position, as marked,
in a clear area that will permit extraction of the
transmitter without risk of damage to the unit or
injury to personnel.
(b) Remove the panel identified as the top from the
crate by carefully prying it open using a small
pry bar or other suitable tool.
(c) Remove the two wooden braces securing the
transmitter and carefully remove the transmitter
cabinet.
(d) Perform a visual inspection of the transmitter
cabinet and its assemblies ad detailed in
paragraph 3.1.1.
3.5.2
POWER SUPPLY MODULE CRATE:
The power supply modules are packed fully
assembled in a wooden crate that is approximately 65
cm (25 inches) x 72 cm (28 inches) x 43 cm (17
inches). Shipping weight is approximately 110
kilograms (245 pounds). Open crate and remove
modules as follows:
(a) Locate the crate in an upright position, as
marked on the crate, in a clear area that will
permit extraction of the power supply modules
without risk of damage to the unit or injury to
personnel.
(b) Remove the panel identified as the top from the
crate by carefully prying it open using a small
pry bar or other suitable tool.
(c) Carefully remove the two power supply
modules and place at a location near the
transmitter cabinet.
(d) Perform a visual inspection of power supply
modules as detailed in paragraph 3.1.1.
(e) Do not install power supply modules in
transmitter cabinet at this time.
